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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, DC 20549
FORM 10-K
(Mark One)
ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the fiscal year ended December 31, 2023
OR 
TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the transition period from             to             
Commission File Number: 001-34674
Calix, Inc.
(Exact Name of Registrant as Specified in Its Charter)
Delaware 68-0438710
(State or Other Jurisdiction of
Incorporation or Organization)
 (I.R.S. Employer
Identification No.)
2777 Orchard Parkway
San Jose, California
(Address of Principal Executive Offices)
95134
(Zip Code)
Registrant’s telephone number, including area code (408514-3000

Securities registered pursuant to Section 12(b) of the Act:
Title of each classTrading symbolName of each exchange on which registered
Common Stock, $0.025 par valueCALXThe New York Stock Exchange
Securities registered pursuant to section 12(g) of the Act:
None
(Title of class)
Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.   Yes:  o    No:  x
Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.   Yes:  o    No:  x
Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    Yes:  x    No:  o
Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).    Yes:  x    No:  o
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.
Large Accelerated FilerAccelerated Filer
Non-accelerated filerSmaller Reporting Company
Emerging Growth Company
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act). o
Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report.

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements. o
Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant's executive officers during the relevant recovery period pursuant to Section 240.10D-1(b). o
Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).    Yes:     No:  x
The aggregate market value of the Common Stock held by non-affiliates of the registrant based upon the closing sale price on the New York Stock Exchange on June 30, 2023, the last business day of the Registrant’s most recently completed second fiscal quarter, was approximately $2,926 million. Shares held by each executive officer, director and by each other person (if any) who owns more than 10% of the outstanding common stock have been excluded in that such persons may be deemed to be affiliates. This determination of affiliate status is not necessarily a conclusive determination for other purposes.
As of February 9, 2024, the number of shares of the registrant’s common stock outstanding was 65,409,170.
DOCUMENTS INCORPORATED BY REFERENCE
Portions of the registrant’s 2023 annual report and definitive proxy statement for its 2024 annual meeting of stockholders are incorporated by reference in Item 5 of Part II and Items 10, 11, 12, 13 and 14 of Part III.





Calix, Inc.
Form 10-K
TABLE OF CONTENTS
PART I
Item 1.
Item 1A.
Item 1B.
Item 1C.
Item 2.
Item 3.
Item 4.
PART II
Item 5.
Item 6.
Item 7.
Item 7A.
Item 8.
Item 9.
Item 9A.
Item 9B.
Item 9C.
PART III
Item 10.
Item 11.
Item 12.
Item 13.
Item 14.
PART IV
Item 15.
Item 16.

2


SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS
Calix, Inc., together with its subsidiaries, is referred to in this document as “Calix,” “we,” “our” or “us.” This report includes forward-looking statements that involve substantial risks and uncertainties. All statements other than statements of historical facts contained in this report, including statements regarding Calix’s future financial position, business strategy and plans, product projections, anticipated market and industry trends and objectives of management for future operations, are forward-looking statements. In some cases, you can identify forward-looking statements by terminology such as “believe,” “could,” “expect,” “may,” “estimate,” “continue,” “anticipate,” “intend,” “should,” “plan,” “predict,” “will,” “would,” “project,” “potential” or the negative of these terms or other similar expressions. Forward-looking statements include Calix’s expectations concerning the outlook for its business, productivity, plans and goals for future operational improvements and capital investments, operational performance, future market conditions or economic performance and developments in the capital and credit markets and expected future financial performance.
Forward-looking statements involve a number of risks, uncertainties and assumptions, and actual results or events may differ materially from those projected or implied in those statements. Important factors that could cause such differences include:
our ability to predict our revenue and reduce and control costs related to our products or service offerings;
fluctuations in our gross margin;
our ability to manage our relationships with our third-party vendors, including contract manufacturers, or CMs, original design manufacturers, or ODMs, logistics providers, component suppliers and development partners;
our ability to forecast our manufacturing requirements and manage our inventory;
supply chain constraints and cost increases for components, shipping and logistics;
our dependence on sole-, single- and limited-source suppliers, some of which are located primarily or solely in China, and other factors;
our ability to build and sustain an adequate and secure information technology infrastructure;
the quality of our products, including any undetected hardware and software defects or software bugs;
our ability to ramp sales and achieve market acceptance of our new products and broadband service providers’, or BSPs’, willingness to deploy our new products;
the capital spending patterns of BSPs, and any decrease or delay in capital spending by BSPs due to macro-economic conditions, regulatory uncertainties or other reasons;
the impact of government-sponsored programs on our customers and the impact to our customers of a United States, or U.S., government shutdown;
our ability to develop new products or enhancements that support technological advances and meet changing BSP requirements;
the length and unpredictability of our sales cycles and timing of orders;
our lack of long-term, committed-volume purchase contracts with our customers;
intense competition and our ability to increase our sales to larger BSPs globally;
our exposure to the credit risks of our customers;
the interoperability of our products with BSP networks;
our ability to estimate future warranty obligations due to product failure rates;
our products’ compliance with industry standards;
our ability to expand our international operations;
our ability to protect our intellectual property, or IP, and the cost of doing so;
our ability to obtain necessary third-party technology licenses at reasonable costs;
the regulatory and physical impacts of climate change and other natural events;
the attraction and retention of qualified employees and key management personnel; and
our ability to maintain proper and effective internal controls.
We caution you against placing undue reliance on forward-looking statements, which reflect our current beliefs and are based on information currently available to us as of the date a forward-looking statement is made. Forward-looking statements set forth in this Annual Report on Form 10-K speak only as of the date of its filing. We undertake no obligation to revise forward-looking statements to reflect future events, changes in circumstances or changes in beliefs. In the event that we do update any forward-looking statements, no inference should be made that we will make additional updates with respect to that statement, related matters or any other forward-looking statements.
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PART I

ITEM 1.    Business
Company Overview
Calix was founded in 1999. We develop, market and sell our platform (cloud, software and systems) and managed services that enable service providers of all types and sizes to innovate and transform their businesses. For our customers to successfully transform their businesses into the innovative broadband service providers, or BSPs, of the future, they require actionable data for critical business functions such as network operations, customer support and marketing. However, this data is often trapped in disparate systems or departmental silos. Our platform, which includes Calix Cloud, Revenue EDGE and Intelligent Access EDGE, gathers, analyzes and applies machine learning to deliver real-time insights seamlessly to each key business function. Our customers utilize these data and insights to simplify network operations, marketing and customer support and deliver a growing portfolio of SmartLife managed services and experiences that excite their subscribers. This enables BSPs to grow their brand through increased subscriber acquisition, loyalty and revenue and to reduce their operating costs, creating value for their businesses and the communities they serve.
This is our mission: to enable BSPs of all sizes to simplify, excite and grow.
We believe our platform offers a competitive edge to BSPs at a critical time of increasing competition from direct-to-consumer cloud companies and device providers as they expand their reach and focus on owning the connected home experience. For example, these over-the-top competitors are entering the home by offering Wi-Fi enabled devices, and then leveraging behavioral insights to expand their direct relationship and build their brand, not the BSP’s, with the subscriber by offering additional consumer services. Over time, we expect this competition can erode a BSP’s brand and relationship with its subscribers, by reducing broadband to an easy-to-replace commodity, which can increase churn and reduce revenue. Our platform enables BSPs to build next generation networks and offer higher-value managed service offerings that enable them to grow revenue, increase subscriber loyalty and monetize their network investments.
Innovative BSPs, who embrace our platform, understand this competitive threat and that their brand’s central position in the home is their most valuable strategic asset. As such, they must protect and expand continually. Our Intelligent Access EDGE network solution and Revenue EDGE subscriber solution are designed to allow BSPs to simplify their businesses and reduce operating costs, while launching exciting new services in a matter of days and weeks instead of months and years. Our role-based cloud enables BSP teams, such as marketing, operations or customer support, to leverage real-time behavioral analytics to anticipate the subscriber’s needs, whether they are in the home, roaming across the town or managing a small business. Our platform is built to enable BSPs to quickly and easily deploy a growing portfolio of SmartLife managed services to connect entire communities. This enables BSPs to establish themselves as essential technology innovators that are enabling their communities to grow and thrive.
The BSPs’ teams can utilize insights from Calix Cloud to offer these new and innovative services to those subscribers who have the propensity to buy, thereby growing revenue as they deliver a connected experience at significantly lower operating costs. This also enables them to build their brand and value proposition around innovation and subscriber experience. As a result, many of Calix’s BSP customers have experienced improved customer satisfaction scores, minimal churn and significant growth. To expand our reach in the market, we will continue to pursue strategic technology and distribution relationships that align with BSPs’ strategic priorities. At the same time, we offer our Calix Customer Success and Support Services along with a growing portfolio of award-winning market activation resources that provide the BSPs with best practices and programs to strengthen and grow their brand with their subscribers, thereby increasing subscriber loyalty and opportunities to grow their subscriber base.
Strategy Overview
Our strategy is to position Calix as the key partner providing a broadband delivery platform (cloud, software and systems) and managed services to enable and facilitate the transformation of BSP networks and the residential and small business network experience in order to excite all of their subscribers. Most BSPs will require transformation of their business and operations to become an essential provider of data-driven, high-value managed services to their subscribers. The principal elements of our strategy are:
Starting with the data – The principal way we gather, analyze and deliver actionable insights for BSPs is via the Calix Cloud. Our role-based Calix Cloud enables critical functions within a BSP’s business, such as marketing, operations and support, to leverage real-time data to continually understand and optimize the experience for their subscribers.
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Building and evolving our platform – Our product strategy centers on our strategic platform. Our platform simplifies BSPs’ businesses by delivering intelligence and automation across the entire subscriber facing network – from the data center edge to the subscriber’s devices. Our strategy is to continually augment and extend our platform with features and services directly or through partners to allow our BSP customers to deliver cutting-edge services to their subscribers.
Engaging directly with BSP customers – We continue to invest in our direct sales capabilities so that we can engage deeply with our BSP customers to help them understand the differentiable value that our platform provides. As we deploy new solutions, we are building the expertise of our team by adding specialized resources in areas such as marketing, cloud and network operations. Our direct model is complemented with selective programs for our channel partners, who have established local market expertise and have demonstrated the ability to generate new market opportunities and support sales of cutting-edge technologies for BSPs.
Expanding customer footprint across our total addressable opportunity – Our total addressable opportunity includes service providers of any type and size, including local and competitive exchange carriers, cable multiple system operators, or cable MSOs, wireless internet service providers, or WISPs, fiber overbuilders such as municipalities and electric cooperatives and tribal communities, multiple dwelling units and hospitality providers. For the past four years, we have averaged adding over 90 new BSP customers per year purchasing directly or through our partners. Our diverse and growing customer footprint is a critical source of our future growth as we expand our portfolio and sell additional components of our platform and managed services to both new and existing customers. Our platform enables us to expand our total addressable opportunity and recurring revenue streams by allowing us to address the needs of not only traditional wireline-focused service providers, but also emerging service providers. As such, we intend to continue to engage emerging providers that are creating entirely new customer segments, including fiber overbuilders, utilities and municipalities. We will also continue to pursue service provider segments where there is an opportunity to grow our current share, such as cable MSOs, large traditional wireline-focused service providers and international markets.
Extending portfolio of Calix services – Our services team, Calix Services, supports our BSPs as they define their transformation strategies, build new skills, implement new technologies and deploy new subscriber services. Calix Services’ capabilities address the BSP’s entire network and service delivery lifecycle. These services allow BSPs to benefit directly from our deep expertise working with service providers to optimize their operations and leverage our advanced analytics to improve the operational efficiency of their teams.
Pursuing strategic relationships – We will continue to pursue strategic technology and distribution relationships that help us align with BSPs’ strategic priorities. We continue to invest to provide technical synergy across the ecosystems that support our customers’ most critical business processes through our partner program. By adding new solutions to our platform ecosystem, we significantly enhance the value that our platform delivers to BSPs. In addition, we are expanding our relationships with organizations that help our customers plan and execute in-market. Examples of these partners are Conexon Connect, LLC, ePlus Technology, inc. and The Pivot Group, LLC.
Product Overview
Our product strategy centers on increasing the market adoption of two fundamental components:
1.Our Calix Platform, which consists of:
Calix Cloud®, which comes in three role-base editions: Calix Engagement Cloud (formerly Calix Marketing Cloud), Calix Service Cloud (formerly Calix Support Cloud) and Calix Operations Cloud.
Calix Intelligent Access EDGE™, access network solution for automated, intelligent next generation networks.
Calix Revenue EDGE™, our premises solution for subscriber managed services.
2.Our SmartLife managed services offerings, which consist of:
SmartHome™ managed services and applications to enhance, operate and secure the connected experience of subscribers in their home, including managed Wi-Fi, advanced content control, network security, connected cameras, social media monitoring for kids and device protection programs.
SmartTown® managed services that reimagine community Wi-Fi as a ubiquitous, secure and managed experience across a BSP’s footprint by making their town a SmartTown. By leveraging residential and small business Wi-Fi systems combined with strategically deployed outdoor Wi-Fi access points, BSPs can serve subscribers, schools, municipalities, organizations, planned communities and more. These opportunities open new markets and relationships with the public sector to reduce reliance on and protect against 5G LTE fixed wireless access.
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SmartBiz™ managed services that address the business networking and productivity needs of small business owners with an all-in-one managed service that increases staff productivity, secures critical business systems and enhances customer loyalty.
Each managed subscriber service is complemented by real-time subscriber insights via Calix Engagement Cloud, Calix Service Cloud and Calix Operations Cloud offerings, which are configurable to display role-based insights for BSP general management, marketing, support, operations and engineering staff. These insights enable BSPs to anticipate and target new revenue-generating services and applications through our mobile application, CommandIQ® for residents and CommandWorx for businesses. Our Calix Cloud enables simple integrations with other market-leading workflow solutions for marketing (including Facebook, Mailchimp, Constant Contact and HubSpot), support ticketing solutions and operations support systems and business support systems.
The SmartLife™ managed services are built on the Calix Platform and fully integrated with our GigaSpire® and GigaPro® family of Wi-Fi systems to be ready for deployment as a complete subscriber experience solution for a BSP’s residential subscribers, small business subscribers and community networks. Calix customers are evolving their go-to-market strategies to go beyond marketing broadband speed. Increasingly, they are becoming “experience” providers by delivering valuable managed services built on top of their Wi-Fi offerings. This unique portfolio gives BSPs more opportunities to provide differentiated services to their subscribers and grow their revenue.
Our access network solutions redefine the access edge of the network by simplifying its architecture and operations. The Calix Platform’s access network component is implemented in our E-Series family of modular, non-blocking systems, enabling BSPs to meet a wide variety of deployment scenarios. BSPs can consolidate multiple access network elements into a single system using specialized software modules that add functionality and remove complexity, thereby reducing the total cost of ownership and the time to market for new services. We offer a range of training, professional and success services to assist BSPs in every domain of network management from strategy to deployment and management.
These offerings are sold independently and offer unique entry points for new customers who are partnering with Calix to transform their businesses. Moreover, an increased segment of our customer base is leveraging all components of our platform and managed services in an end-to-end strategy to simplify their businesses, excite their subscribers and grow the value that they deliver for their subscribers and communities.
Finally, to support these managed services, we offer market activation resources and customer support programs through our customer success organization to enable BSP teams to quickly deploy, manage and monetize each service that they provide to subscribers. These resources include marketing content that can be easily customized with on-line tools, training programs, success services and professional services.
Customers
We market and sell our platform (cloud, software and systems) and managed services to service providers of all types and sizes. To date, we have focused primarily on service providers in the North American market. Our customers span all sizes of broadband subscriber count from a few hundred to more than six million. We currently have approximately 1,600 active service provider customers, purchasing directly and through partners, to deploy passive optical, Active Ethernet or point-to-point Ethernet access networks or subscriber premise systems. Our service provider customers include: ALLO Communications; Connect Holding II, LLC (dba Brightspeed); CityFibre Holdings Limited; Conexon Connect; Cox Communications; Gibson Connect, LLC; Hunter Communications; Jade Communications; Gridiron Fiber Corporation (DBA Lumos); Lumen Technologies, Inc., or Lumen; Paul Bunyan Communications; Silver Star Communications; Tombigbee Electric Power Association and Tombigbee Fiber, LLC and Verizon Communications, Inc.
The U.S. Federal government has approved programs, totaling more than $60 billion, to fund broadband and connectivity expansion across the United States. Calix has a dedicated team of funding specialists, assisting our customers with the most up-to-date information on broadband funding opportunities as they are introduced and personalized strategies to maximize their grants to support their growth.
We classify service providers into large, medium and small based on the number of broadband subscribers they serve. Large service providers are those with wide geographic footprints and broadband subscribers of 2.5 million or more. Medium service providers also operate typically within a wide geographic footprint but are smaller in scale with broadband subscribers that range from 250,000 to 2.5 million. Small service providers consist primarily of over 1,000 predominantly local independent operating companies, or IOCs, typically focused on a single community or a cluster of communities. They include a growing number of municipalities, cable MSOs, electric cooperatives, fiber overbuilders and WISPs. These entities range in size from a few hundred to 250,000 broadband subscribers.
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No customer represented more than 10% of revenue in 2023, 2022 or 2021. Sales to customers outside the United States represented 9% of our revenue in 2023, 9% of our revenue in 2022 and 17% of our revenue in 2021. Our sales outside the United States have been and are currently predominantly to customers in the Americas and Europe.
Customer Engagement Model
We market, sell and support the success of our platform and managed services predominantly through our direct sales force, supported by marketing, product management and customer success personnel. We have also expanded this model to include select channel partners in North America and more than 40 international channel partners. Even in circumstances where a channel partner is involved, our sales and marketing personnel are generally selling side-by-side with the channel partner. We believe that our direct customer engagement approach provides us with significant differentiation in the customer sales process and customer engagement programs by aligning us more closely with our customers’ changing needs and successful implementation of our solutions.
Research and Development
Continued investment in research and development is critical to our business. We have made significant investments in our product portfolio, and we intend to continue to dedicate significant resources to research and development to develop, enhance and deliver new platform features and capabilities, including investments in innovative technologies that support our business strategy. Our research and development team is composed of engineers with expertise in software and cloud platforms, optics, wireless technologies and systems engineering. Our research and development team is responsible for designing, developing and enhancing our platform and managed services, performing product and quality assurance testing and ensuring the compatibility of our products with third-party hardware and software products. Increasingly, our engineers are focused on enhancements to our cloud and software platform components. Our teams of engineers currently remain concentrated in San Jose and Petaluma, California; Nanjing, China; Bangalore, India; Minneapolis, Minnesota and Richardson, Texas. We also outsource a portion of our software and cloud development to domestic and international third parties and depend on these partners to meet our development plans.
Manufacturing and Supply Chain
We rely on CMs, ODMs and third-party logistics partners for the supply and distribution of our products. Our global supply chain management organization oversees these third parties to source and procure materials, manufacture and deliver our products. Our global supply chain management organization consists of order management, planning, sourcing, logistics, test and manufacturing engineers and new product introduction personnel. We tightly integrate our supply chain management and new product introduction activities with the activities outsourced to these third parties. We believe that our relationships with and our reliance on third parties allow us to improve new product introduction time, conserve working capital, reduce product costs and minimize delivery lead times while maintaining high product quality as well as the ability to scale quickly to handle increased order volume. We continue to qualify and utilize additional vendors for various portions of our supply chain from time to time.
The COVID-19 pandemic-induced global demand surge resulted in supply chain challenges, including component shortages or unavailability, end-of-life notifications, extended lead times, elongated transit times, port congestion, spot market purchases, multiple price increases and surcharges. These challenges abated during 2023. The overhang from these events is a buildup of inventory in the supply chain. At our direction, our suppliers built up inventory to buffer against the long lead-times for semiconductors and other electronic components. We are using this as an opportunity to realign our strategic buffer inventory to protect against future disruptions. Most of the excess inventory will be worked off during the normal course of business. As time goes on, there may be components that become obsolete due to technology shifts or demand changes. This will be reflected in our inventory reserve balance as it becomes apparent during our financial reviews. For example, during the fourth quarter of 2023, we wrote down obsolete inventory and accrued a liability for components at suppliers primarily related to the wind down of our legacy product family that existed before our shift to an all-platform model.
Seasonality
Fluctuations in our revenue occur due to many factors, including the varying budget cycles and seasonal buying patterns of our customers. More specifically, our customers tend to spend less in the first fiscal quarter as they are finalizing their annual capital spending budgets, and in certain regions, customers are also challenged by winter weather conditions that inhibit outside fiber deployment. In recent years, as our revenue from our large customers decreased, we have experienced less year-end volatility due to capital budgetary spending or freezing. This, combined with an increase in recurring revenue, has resulted in smaller seasonal fluctuations, and we expect this trend to continue.
Competition
The communications software and systems equipment markets are highly competitive. Competition is largely based on any one or a combination of the following factors: functionality and features, price, existing business and customer relationships,
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product quality, installation capability, service and support, long-term returns, scalability, development and manufacturing capability.
We compete with several companies within the markets that we serve, and we anticipate that competition will intensify. Vendors with which we compete include: ADTRAN, Inc.; Ciena Corporation; CommScope Inc.; DZS Inc.; eero/Ring (Amazon companies); Harmonic, Inc.; Huawei Technologies Co., Ltd.; Google Nest (a Google company); Nokia Corporation; Plume Design, Inc. and Ubiquiti Inc. In various geographic or vertical markets, there are also several smaller companies with which we compete. As we expand into adjacent markets, we expect to encounter new competitors. Many of our competitors have the financial resources to offer competitive products at a below market price, which could prevent us from competing effectively.
Intellectual Property
We rely on a combination of IP rights, including patents, trade secrets, copyrights and trademarks as well as customary contractual protections. These rights and protections are accomplished through a combination of internal and external controls, including contractual protections with employees, contractors, customers and partners, and through a combination of U.S. and international IP laws.
As of December 31, 2023, we held 111 U.S. patents and 26 pending U.S. and international patent applications. U.S. patents generally have a term of twenty years from filing. The remaining terms on our individual patents vary from less than a year to seventeen years. U.S. patent, copyright and trade secret laws afford us only limited protection, and the laws of some foreign countries do not protect proprietary rights to the same extent.
We believe that the frequency of assertions of patent infringement has and continues to increase in our industry. Any claim of infringement from a third party, even claims without merit, could cause us to incur substantial costs defending against such claims, could require us to pay substantial damages or include an injunction or other court order that could prevent us from selling our products. In addition, we might be required to seek a license which may not be available on commercially reasonable terms or at all. Alternatively, we may be required to develop non-infringing technology, which would require significant effort and expense.
Human Capital
We employed 1,760 employees globally as of December 31, 2023 with 1,055 employees located in the United States and 705 outside of the United States, primarily in Canada, China and India. Except for one employee located in France and subject to customary local collective bargaining arrangements, we do not have any employees represented by a labor union with respect to their employment with us. We have not experienced any work stoppages and consider our relations with our employees to be good. We consider our talent to be very important to our operations and execution of our business strategy as well as the overall success of our business. As such, we invest significant management attention, time and resources to attract, engage, develop and retain our talent. Our talent strategy focuses on our culture and core values, our talent programs and the overall well-being and safety of our talent.
Culture and values. At Calix, we believe culture is how each employee treats their teammates, customers and partners every day. Each employee is entrusted with our culture to create a positive work experience for all. This is grounded by each employee knowing their purpose, their commitment to creativity, collaboration and communication as well as investing in the success of others. From leadership down, Calix embraces a “better, better, never best” philosophy, which we believe encourages continuous improvement and experimentation. This culture enables Calix to deliver on its mission to help BSPs simplify their businesses, excite their subscribers and grow value for their communities.
Talent Development. We prioritize the ongoing professional growth of our team by providing on-demand access to training through top-notch industry platforms. Additionally, we provide educational resources and the chance to glean insights from subject matter experts spanning diverse topics. Our commitment extends globally, fostering a collaborative space for leaders to connect and evolve as Calix champions. Complementing these efforts, we offer valuable developmental opportunities such as stretch assignments and participation in our mentorship program. We firmly believe that sustained investment in the skills and knowledge of our team is pivotal to ensuring our enduring success.
Diversity, Equity and Inclusion. At Calix, we strive to create an inclusive culture that values diversity, promotes equity and celebrates the differences among us. We believe a diverse workforce is at the core of our innovation and drives productivity and growth. Our diversity and inclusion strategy takes into consideration the entire employee life cycle, from recruitment, to learning and development and total rewards. We support a range of employee programs and initiatives designed to foster belonging, engagement, acceptance and diversity through employee-led affinity groups, leadership events, meetups and celebrations. We are proud and honored to be recognized by industry experts for our diverse culture.
Community Outreach. Calix is committed to creating a positive social impact by leveraging our resources, expertise and network to address pressing societal challenges. We strive to give back to the community whenever possible. To establish a rhythm and cadence, Calix sponsors two major giving campaigns throughout the year – National Volunteer Month in April and
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Season of Giving in the fourth quarter as well as ongoing initiatives throughout the year. We believe together we can be a force for good and are determined to drive change in the communities where we operate and beyond.
Our wellness, safety and health programs. At Calix, employee well-being is crucial to creating a healthy workplace where employees can do their best work. We recognize that employees have diverse needs when it comes to health and well-being and provide an expanded library of tools and apps, including “Unmind,” an app that provides digital tools and techniques designed to empower employees to live a more fulfilling and balanced life. To further support employees and their wellness journey, we launched a “LifeStyle” Wellness Reimbursement Program that offers employees a quarterly wellness allowance to help employees reach their personal wellness goals and support a healthy lifestyle. We also implemented Productivity and Recharge Days and a Leadership Cares program for leaders to send gifts to employees. We believe that these initiatives have helped Calix become a top company to work for.
Corporate Information
Our principal executive offices are located at: 2777 Orchard Parkway, San Jose, California 95134, and our telephone number is (408) 514-3000. Our website address is: www.calix.com. We do not incorporate the information on or accessible through our website into this Annual Report on Form 10-K, and you should not consider any information on, or that can be accessed through, our website as part of this Annual Report on Form 10-K. Calix®, the Calix logo design, AXOS®, Calix Cloud®, CommandIQ®, CommandWorx, GigaPro®, GigaSpire®, SmartTown® and other trademarks or service marks of Calix appearing in this Annual Report on Form 10-K are the property of Calix. Trade names, trademarks and service marks of other companies appearing in this Annual Report on Form 10-K are the property of the respective holders. The Securities and Exchange Commission, or SEC, maintains a website at www.sec.gov that contains reports, proxy statements and other information regarding issuers that file electronically with the SEC. We post on the Investor Relations page of our website, www.calix.com, a link to our filings with the SEC free of charge, as soon as reasonably practical after they are filed electronically with the SEC.
ITEM 1A. Risk Factors
We have identified the following additional risks and uncertainties that may affect our business, financial condition and/or results of operations. Investors should carefully consider the risks described below, together with the other information set forth in this Annual Report on Form 10-K, before making any investment decision. The risks described below are not the only ones we face. Additional risks not currently known to us or that we currently believe are immaterial may also significantly impair our business operations. Our business could be harmed by any of these risks. The trading price of our common stock could decline due to any of these risks, and investors may lose all or part of their investment.
Business and Operational Risks
We face risks associated with being materially dependent upon third-party vendors; certain factors that affect our business as a result of those dependencies have and could continue to disrupt our business and adversely impact our gross margin and results of operations.
We materially depend upon third-party vendors for our complex global supply-chain operations, including for services to develop, design and source components and materials, as well as manufacture, transport and deliver our products. If any of these vendors stop providing their services, for any reason, we would have to obtain similar services from other sources, which may not be available on commercially reasonable terms, if at all. We also have limited control over disruptions that may occur at the facilities of those providers, such as supply interruptions, labor shortages, strikes, shipping backlogs at ports and similar disruptions to transportation infrastructure, design and manufacturing failures, quality control issues, systems failures or even facility closures arising from pandemics or natural disasters. In addition, switching development firms or manufacturers could delay the manufacture and availability of products and/or require us to re-qualify our products with our customers, which would be costly and time-consuming. Any interruption in the development, supply or distribution of our products would adversely affect our ability to meet scheduled product deliveries to our customers and could result in lost revenue or higher costs, which would negatively impact our gross margin and operating results and harm our business.
Particular risks associated with management of our global supply chain operations include the following:
Manufacturing constraints, shortages and other disruptions. We do not have internal manufacturing capabilities and rely solely on a small number of CMs and ODMs to manufacture and supply our products. Our business operations and ability to supply our products are highly dependent upon our ability to secure adequate third-party manufacturing capabilities and capacity and to effectively manage those third parties to meet our business needs. Our dependence solely on third-party manufacturers makes us vulnerable to possible supply and capacity constraints and reduces our control over manufacturing disruptions due to component availability, extended lead times delivery schedules, quality, manufacturing yields and increased costs. Some of these risks occur from time to time in our business, including recent increases in component costs. If these disruptions and constraints are prolonged, or if these manufacturers do not have
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the ability or business continuity plans to fulfill their obligations to us, our business could be disrupted. If we cannot effectively manage our vendors or if we fail to invest adequate resources to manage our supply chain operations, our ability to meet customer orders and generate revenue may be negatively impacted. A substantial portion of our manufacturing is done at facilities outside of the U.S., largely in Asia, which presents increased supply risk, including the risk of supply interruptions, delays, shortages or reductions in manufacturing quality or controls. In addition, these supply interruptions, delays and shortages could impair our ability to meet our customer requirements, require us to pay higher prices or incur expedite fees, which would harm our business and negatively impact our gross margin and results of operations. Our international manufacturing also creates risks and uncertainties associated with regulatory changes or government actions such as local business requirements, trade restrictions and tariffs, economic sanctions or related legislation, which may complicate our export and import activities, be disruptive to the operations of our manufacturers and logistics partners or result in higher product and shipping costs and variability of supply. For example, in 2022, substantially all our silicon suppliers extended their lead times and increased prices. Prices remain high, and while many silicon suppliers have begun reducing their lead-times, we continue to face extended lead times. Manufacturing in Asia further heightens our risk of meeting customer delivery requirements as we rely upon third-party logistics companies to transport and import significant volumes of products to the U.S. where we generate a substantial majority of our revenue. These supply chain risks are further increased by periodic shipping backlogs at ports and similar disruptions to transportation infrastructure.
Limited sources and sole-sourced supply. We are dependent upon sole-source or limited-source suppliers for some key product components such as chipsets and certain of our application-specific integrated circuit processors and resistor components, including certain components sourced solely through suppliers located in China and other Asian countries. Any of these suppliers could stop producing our components, raise the prices they charge us, be subject to higher product tariffs, epidemics or other conditions that disrupt their operations, cease operations or enter into exclusive arrangements with our competitors, consequently affecting our operations and results. For example, we have experienced disruptions in our supply of certain components that we source from suppliers in China and other Asian countries due to production disruptions, factory closures and longer lead times for components and from uncertainty around trade and tariff policies between the U.S. and China, which caused delays in our product supply. Being dependent upon a limited number of suppliers constrains our ability to mitigate these disruptions in our supply chain, particularly if such disruptions are prolonged. This may adversely affect our ability to obtain components and materials needed to manufacture our products at acceptable prices or at all. These risks would adversely affect our ability to meet scheduled product deliveries to our customers, increase costs and in turn harm our business and results of operations.
Limitations on ability to manage third-party risks. Our business with certain third-party manufacturers may represent a relatively small percentage of their revenue. Consequently, our orders may not be given adequate priority if such manufacturers have to allocate limited capacity among competing customers. This could delay supplies of product to us or limit our ability to ramp product volumes within desired timeframes. If any of our manufacturing partners are unable or unwilling to continue manufacturing our products in required volumes and at high quality levels, we would have to identify, qualify and select acceptable alternative manufacturers. The time it takes to qualify new third-party manufacturers could disrupt our ability to maintain continuous supply of product to meet customer requirements. An alternative manufacturer may not be available to us when needed or may not be in a position to satisfy our production requirements at commercially reasonable prices and quality. In addition, we and/or our manufacturers may not be able to negotiate commercially reasonable terms and sufficient quantities of component supplies with component and materials suppliers to meet our manufacturing needs because our purchase volumes may be too low for us to be considered a priority customer for securing supplies, particularly when there are shortages or limited availability of key components and materials. As a result, suppliers could stop selling to us and our manufacturers at commercially reasonable prices, or at all. While we have worked to mitigate the cost impact of recent price increases, those efforts may not be successful. Any such interruption or delay may force us and our manufacturers to seek components or materials from alternative sources, which may not be available, or result in higher prices. Switching suppliers could also force us to redesign our products to accommodate new components and could require us to re-qualify our products with our customers, which would be costly and time consuming. A significant interruption in manufacturing or supply availability for any of these reasons would reduce supply to our customers, which would result in lost revenue and harm our customer relationships.
Ability to forecast and manage inventory liability with vendors. We have experienced increases in demand from many customers, in part as a result of higher consumer demand for internet services and improved Wi-Fi; in turn, this has resulted in our shipments being delayed. If we underestimate product demand from our customers, our manufacturers may have inadequate component inventory to meet our demand. If we are not able to adequately anticipate demand, this could interrupt our product manufacturing, increase our cost of revenue associated with expedite fees and air freight and/or result in delays or cancellation of customer orders. If we are unable to deliver products timely to our
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customers, we may lose customer goodwill or our customers may choose to purchase from other vendors, all of which may have a material negative impact on our revenue and operating results. If we overestimate our product demand, our third-party manufacturers may purchase excess components and build excess inventory, and we could be required to pay for these excess parts or products and their storage costs. For example, as of December 31, 2023, we had inventory deposits totaling $78.1 million. Long lead times for component supply, which have been exacerbated by higher demand for certain components, and demand for our products has and is expected to continue to impact our ability to accurately forecast our production requirements. We may incur liabilities for certain component inventory purchases that have been rendered excess or obsolete, which may have an adverse effect on our gross margin, financial condition and results of operations. For example, during the fourth quarter of 2023, we wrote down excess and obsolete inventory and accrued a liability for components at suppliers primarily related to the wind down of our legacy product family that existed before our shift to an all-platform model.
Cyberattacks or other security incidents that disrupt our operations or compromise data, may expose us to liability, harm our reputation or otherwise adversely affect our business.
We rely on hardware, software, technology infrastructure, data centers, digital networks and online sites and services for both internal and customer-facing operations that are critical to our business, or collectively, IT Systems. In addition, as part of our business operations, we collect, store, process, use and/or disclose information, including sensitive data relating to our business and personal information about individuals such as our employees and our customers’ subscribers, or collectively, Confidential Information. We process Confidential Information to operate our business, including in connection with the provision of our cloud services and by relying on our and our providers’ IT Systems and data centers, including third-party data centers. We also engage third-party providers to support various internal functions, such as human resources, finance, information technology and electronic communications, as well as the development and delivery of our customer-facing products and cloud services, which includes collecting, handling, processing and/or storage of data on our behalf. These internal and external functions involve an array of software and systems, including cloud-based, that enable us to conduct, monitor and/or protect our business, operations, systems and information technology assets. Our cloud-based solutions enable us to host our customers’ subscriber data in third-party data centers.
We face evolving cybersecurity risks that threaten the confidentiality, integrity and availability of our IT Systems and Confidential Information, including from diverse threat actors such as state-sponsored organizations, opportunistic hackers and hacktivists, as well as through diverse attack vectors such as social engineering/phishing, malware (including ransomware), malfeasance by insiders, human or technological error and, as a result of bugs, misconfigurations or exploited vulnerabilities in software or hardware. Threat actors could steal Confidential Information related to our business, products, employees, customers and our customers’ subscribers; hold data ransom; and/or disrupt our systems and services or those of our supply chain partners, vendors, customers or others. We expect cybersecurity attacks and security breaches to accelerate in the future, including sophisticated supply chain attacks. As we and our third-party providers continue to increase our reliance on virtual environments and communications systems and cloud-based solutions to support our work-from-anywhere culture and overall business needs, our exposures to third-party vulnerabilities and security risks also increase. Because threat actors are increasingly sophisticated and aggressive, our efforts may be inadequate to prevent, detect or recover from future attacks due, for example, to the increased use by attackers of tools and techniques (including artificial intelligence) that are specifically designed to circumvent controls, to avoid detection, and to remove or obfuscate forensic evidence. We may also experience security breaches that may remain undetected for an extended period.
We and certain of our third-party providers have been subject to cyberattacks and other security incidents, and we expect such attacks and incidents to continue in varying degrees. There can be no assurance that our cybersecurity risk management program and processes, including our policies, controls or procedures, will be fully implemented, complied with or effective in protecting our IT Systems and Confidential Information. Accordingly, while to date no cybersecurity incidents have had a material impact on our operations or financial results, we cannot guarantee that material incidents will not occur in the future. A cyberattack or incident that affects the confidentiality, integrity or availability of our IT Systems or Confidential Information could result in significant investigative, security and remediation costs, regulatory fines and penalties and/or litigation costs and other liability. Even if we and our third-party providers allocate, implement and manage reasonable security and data protection measures, we could still experience significant data loss, unauthorized data disclosure or a breach of our IT Systems, products or those of our third-party providers (for example, data centers) that materially impact our business. The continued growth of our cloud-based platform and managed services portfolio and increased reliance on third-party development partners and third-party software and cloud-based solutions increases the likely risks arising from security breaches or data loss. Any data loss or compromise of our systems that collect and process personal information (including personal information of our customers’ subscribers), or third-party data centers where that personal information is stored, could result in loss of confidence in the security of our offerings and loss of customers or customer goodwill. Further, security incidents could subject us to obligations under privacy and data security laws and regulations around the world (including to notify governmental authorities, regulatory bodies and/or affected individuals), lead to liability given the increasing development of such strict laws and regulations,
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increase the risk of litigation and governmental or regulatory investigation, require us to notify our customers or other counterparties in relation to such incidents, damage our reputation and adversely affect our business, financial condition, operating results and cash flows. Although we maintain insurance that may apply to cybersecurity risks and liabilities, there can be no guarantee that any or all costs or losses incurred will be partially or fully insured or that we will be able to procure applicable insurance in the future on reasonable terms or at all.
If we do not successfully increase our sales through adoption of our new platform and managed service offerings, our operating results, financial condition, cash flows and long-term growth may be negatively impacted.
We have platform and managed service offerings that are new and early in their life cycles and subject to uncertain market demand. If our customers are unwilling to adopt these new offerings, install our new products or deploy our new services, or if we are unable to achieve market acceptance of our products and platform, our business and financial results may be harmed. Moreover, adoption of our cloud product offerings, such as our Revenue EDGE, is dependent upon the success of our customers in investing, marketing, selling and deploying broader services—including managed services—to their subscribers, and our ability to differentiate our products from competing or substitutive product and service offerings. For example, our managed services include managed Wi-Fi, network security, parental controls and an ecosystem of services from partners, including Arlo, Bark and Servify. However, if subscriber demand for such services does not grow as expected or declines, or our customers are unable or unwilling to invest in our platform to deploy and market these services, demand for our products may not grow at rates as we anticipate.
Changing market and customer requirements may adversely affect the valuation of our inventory as well as our supplier purchase commitments.
Customer demand for our products can change rapidly in response to market and technology developments. We may, from time to time, adjust inventory valuations downward or end of life certain of our products in response to our assessment of our business strategy as well as consideration of demand from our customers for specific products or product lines. We also periodically evaluate our supplier purchase commitments due to extended lead-times as a result of the global pandemic-induced demand pulse and corresponding impact on the supply-chain environment. We record a liability for excess and obsolete components based on our estimated future demand for our products, potential obsolescence of technology and product life cycles. If we fail to accurately plan our inventory levels, which becomes more challenging as component lead times increase, we may have to increase write offs for excess or obsolete inventory, or accrue additional liabilities for component inventory held by our suppliers, both of which could have a material adverse effect on our financial condition and results of operations. For example, during the fourth quarter of 2023, we wrote down obsolete inventory and accrued a liability for components at suppliers, totaling $28.7 million, primarily related to the wind down of our legacy product family that existed before our shift to an all-platform model.
Business and operational risks associated with expanding our international operations could harm our business.
We are subject to business and operational risks associated with our international operations, including our global supply-chain operations, and our international offices located in Nanjing, China and Bangalore, India as well as dependence upon our international sales operations. In addition, we are exposed to risk arising from dependence upon third-party development contractors in India. The risks associated with our international operations also include costs of complying with differing and changing laws and regulatory requirements, tariffs, export quotas, custom duties and other trade restrictions; effects of inflation, currency controls and/or fluctuations in currency exchange rates; limited, inadequate or non-existent IP protection; and uncertainties associated with political conflicts and instabilities, variable economic conditions, terrorist attacks or acts of war. Our development operations and activities in China and India involve these and other significant risks, including: local labor conditions and regulations; knowledge transfer related to our technology and exposure to misappropriation of IP or confidential information, including information that is proprietary to us, our customers and third parties; heightened exposure to changes in the economic, security, political and pandemic conditions; international trade agreements and U.S. tax provisions that could adversely affect our international operations; complexities of managing development timelines and deliverables from abroad; and differences in local business practices and customs that may not align with our expectations and standards.
Along with the foregoing risks, our international sales operations involve risks associated with greater costs and complexity localizing and supporting our products and platform in local markets; evolving privacy regulations, trade regulations, compliance requirements and incremental costs applicable to the qualification, production, sale and delivery of our products; longer collection periods, financial instability and other difficulties impacting collection of accounts receivable in certain jurisdictions; more intense competition including from local equipment suppliers; and our reliance on value added resellers to sell and support our products in international markets given our limited presence and infrastructure outside the U.S. To expand our international operations, we will need to invest resources to attract key talent, build operational infrastructure, execute on our international strategy and drive international market demand for our products. If we invest substantial resources to expand our international operations and are unable to do so successfully and in a timely manner, our financial condition and results of operations may suffer.
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If we do not successfully execute our business strategy to increase our sales to new and existing BSPs, our operating results, financial condition, cash flows and long-term growth may be negatively impacted.
Our growth depends upon our ability to increase sales to existing and new service providers of all types and sizes, and the execution of our strategy to increase sales to BSPs involves significant risk. The majority of our revenue is not recurring, and our customers generally have no committed purchase requirements, may cancel orders or cease purchasing our products at any time. If our customers stop purchasing our products for any reason, our business and results of operations would be harmed. If we are unable to increase our sales to new and existing BSPs, our operating results, financial condition, cash flows and long-term growth may be negatively impacted. Our strategy includes investing in regional sales teams and select channel partners to sell to smaller regional BSPs. A large portion of our current sales are to customers with smaller regional networks and limited capital expenditure budgets. The spending patterns of many of these customers are generally less formal than larger service providers and often characterized by small and sporadic purchases, and the potential revenue from any one of these customers is limited. We rely primarily on channel partners, including value added resellers, internationally and for certain U.S. markets. We face fierce competition for business with key channel partners. If we are unable to engage channel partners, we may fail to grow our sales, or our sales may be reduced. Furthermore, we rely on our channel partners to promote and sell our products. The loss of a key channel partner or the failure of our partners to provide adequate services could have a negative effect on customer satisfaction and could cause harm to our business.
Our selling efforts to larger BSPs require substantial investments of technical, marketing and sales resources through lengthy equipment qualification and sales cycles without any assurance of generating sales. We may be required to invest in costly upgrades to meet more stringent performance criteria and interoperability requirements, develop new customer-specific features or adapt our products to meet required standards. We have invested and expect to continue to invest considerable time, effort and expenditures, including investment in product research and development, related to these opportunities without any assurance that our efforts will result in revenue.
The quality of our support and services offerings is important to sustain and increase our sales to new and existing customers. Our services to customers include services to help them deploy our products within their networks. Once our products are deployed within our customers’ networks, they depend on our customer success, customer support and research and development organizations to resolve any issues relating to those products. If we do not effectively assist our customers in deploying our products, succeed in helping them quickly resolve post-deployment issues, effectively utilize features or enhancements or provide effective support, it could adversely affect our ability to sell our products to existing customers and harm our reputation with potential new customers. As a result, our failure to maintain high quality support and services could result in the loss of customers, which would harm our business.
We may have difficulty evolving and scaling our business and operations to meet customer and market demand, which could result in lower profitability or cause us to fail to execute on our business strategies.
In order to grow our business, we will need to continually evolve and scale our business and operations to meet customer and market demand. Evolving and scaling our business and operations places increased demands on our management as well as our financial and operational resources to effectively manage organizational change; design scalable processes; accelerate and/or refocus research and development activities; expand our manufacturing, supply chain and distribution capacity; increase our sales and marketing efforts; broaden our customer success, support and services capabilities; maintain or increase operational efficiencies; scale support operations in a cost-effective manner; implement appropriate operational and financial systems; and maintain effective financial disclosure controls and procedures. If we cannot evolve and scale our business and operations effectively, we may not be able to execute our business strategies in a cost-effective manner and our business, financial condition, profitability and results of operations could be adversely affected.
Our business and results of operations have been, and may continue to be, negatively affected by global macroeconomic conditions and supply chain constraints, and the demand for broadband products may not be sustained.
Global macroeconomic, financial and supply chain disruptions have impacted most regions in which we sell our products and services and conduct our business operations. For example, BSPs may not invest in our platform or delay infrastructure improvements due to uncertainty in the global economy. There are no assurances that the demand for our products will remain strong. To the extent we experience a renewed or worsening disruption to our business and operations and other adverse residual impacts of a pandemic or further future disruptions, it could have a material adverse effect on our business, results of operations and financial condition.
Litigation and regulatory proceedings could harm our business or negatively impact our results of operations.
In the ordinary course of business, we are subject to legal claims, litigation and regulatory proceedings related to disputes over commercial, competition, IP, labor and employment and other matters. Regardless of the merits of any such claims, litigation and regulatory proceedings are inherently uncertain, and can be costly, disruptive to our business and operations, harmful to our reputation and distracting to management. In particular, as a technology company, we are subject to IP claims asserting patent,
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copyright, trademark and/or other infringement claims that are costly to defend and could limit our ability to use some technologies in the future. The risk of such claims is heightened as we expand our products and services and rely on more technologies, including third-party IP rights that we license and incorporate into our products and services. Third parties from whom we license IP may be unable or unwilling to indemnify us for such claims or offer any other remedy to us. Patent infringement claims may be asserted by patent assertion entities and non-practicing entities, or NPEs, that do not conduct business as an operating company and hold and own patents only for the purpose of aggressively pursuing royalties through infringement assertions or patent infringement litigation. Further, in our industry, the number of assertions by NPEs has continued to increase due in part to patent sales by operating companies to NPEs and availability of litigation financing. We have received and expect to continue to receive assertions from NPEs and other third parties alleging that we may be infringing their patents or other IP rights; offering licenses to such IP; and/or threatening litigation. If our products are found to infringe, these claims could also result in the suspension of our ability to import, market and sell our products and services, product shipment delays or requirements to modify our products or enter into costly settlements or licensing agreements. Such royalty or licensing agreements, if required, may not be available to us on acceptable terms, if at all. Furthermore, we may additionally be financially responsible for claims made against our customers, including costs of litigation and damages awarded, under indemnity obligations which could further negatively impact our results of operations. Protracted litigation could cause us to incur significant defense costs, which would negatively impact our results of operations.
We have a history of fluctuations in our gross margin and operating results, which can make it difficult to predict our future performance and could cause the market price of our stock to decline.
We have a history of fluctuations in our quarterly and annual gross margin and operating results, including fluctuations due to factors outside of our control. Factors that impact variability of our operating results include our ability to predict our revenue and reduce and control our costs, our ability to predict product functions and features desired by our customers, the impact of global economic conditions, our ability to effectively manage our global supply chain operations, our ability to effectively manage third parties upon whom we depend to conduct our business, our customers’ spending patterns and purchasing decisions, the impact of competition, customer adoption of our products, our ability to manage our legal, contractual and regulatory obligations and liabilities and other risk factors identified in “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and in this “Risk Factors” section. Our gross margin is further impacted by customer, geographic and product mix, the impact of competition on our prices, our ability to manage our costs associated with components and materials, excess and obsolescence, expedite fees and logistics-related activities, contractual commitments and other product costs. Fluctuating results make it difficult to predict our future performance and could cause the market price of our stock to decline. We expect to continue to incur significant expenses and cash outlays as we seek to expand our business and operations and target new customer opportunities. Given our growth objectives and the intense competitive pressures we face, our operating expenses may increase at unexpected levels, and we may be unable to maintain positive operating income. Comparing our operating results on a period-to-period basis may not be meaningful, and you should not rely on our past results as an indication of our future performance. If our revenue or operating results fall below the expectations of investors or securities analysts, or below any guidance we may provide to the market, the market price of our stock would likely decline.
We are exposed to customer credit risks that could adversely affect our operating results and financial condition.
We generally extend credit terms for sales to our customers which exposes us to credit risk. If we are unable to collect our accounts receivable balances as anticipated, our operating results and financial condition will be harmed. A number of factors contribute to this risk, including our ability to adequately assess a customer’s creditworthiness and financial condition, changes in a customer’s financial condition and/or liquidity, our ability to timely collect our accounts receivable from customers, disagreements with customers on invoiced balances and economic downturns or other unanticipated events impacting a customer’s ability to pay. Furthermore, some of our international customers operate in countries with developing economies, volatile financial markets or currency regulations that impact their ability to make payments in U.S. dollars. While we take measures to pursue collections on our accounts receivable, we have from time to time written down accounts receivable and written off doubtful accounts and may need to do so in future periods. The determination of allowances for doubtful accounts involves significant judgment, and if we underestimate our allowance for doubtful accounts, we will have to make further write-downs. Such write-downs or write-offs could negatively affect our operating results for the period in which they occur and could harm our cash flow or our financial condition.
If we lose any of our key personnel, or are unable to attract, train and retain qualified personnel, our ability to manage our business and continue our growth would be negatively impacted.
Our success depends, in large part, on the continued contributions of our key personnel who are highly skilled and would be difficult to replace. Competition for skilled personnel, particularly in software and cloud development and engineering, is intense. We cannot be certain that we will be successful in attracting and retaining qualified personnel, or that newly hired personnel will function effectively, both individually and as a group. If we are unable to effectively recruit, hire and utilize new employees to align with our company objectives, execution of our business strategy and our ability to react to changing market conditions may be impeded, and our business, financial condition and results of operations may suffer. We operate using a
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“work-from-anywhere” model, and if we do not continue to effectively manage our distributed workforce, we could face challenges maintaining our corporate culture, which could increase attrition or limit our ability to attract personnel. None of our key personnel are bound by a written employment contract to remain with us for a specified period. In addition, we do not currently maintain key person life insurance covering our key personnel. If we lose the services of any key personnel, our business, financial condition and results of operations may suffer.
If we experience disruptions with our enterprise resource planning system, we may not be able to effectively transact business or produce financial statements, which would adversely affect our business, results of operations and cash flows.
In January 2020, we migrated our Oracle enterprise resource planning, or ERP, system to Oracle’s cloud platform. In 2022, we implemented a software billing application on Salesforce.com. With these implementations, we are highly dependent upon Oracle and Saleforce.com to host, manage and maintain our ERP system and supporting applications. Any disruptions to their business or processes, or delays in their ability to provide services to us, may in turn disrupt our business operations or increase costs. Furthermore, we receive quarterly system updates and enhancements on the cloud platform according to Oracle’s release timeline and change management processes, which if not managed properly may disrupt our business operations and delay our ability to process transactions and produce reports necessary to conduct our business. We are highly dependent upon our ERP system for critical business functions, including order processing and management, supply chain and procurement operations, financial planning, accounting and reporting; accordingly, protracted disruption in functionality or processing capabilities of the ERP system could materially impair our ability to process transactions timely or produce accurate financial statements on a timely basis. If our systems suffer prolonged interruption, our results of operations and cash flows would be adversely affected.
Risks Related to Our Products
Our products are highly technical and may contain undetected hardware or software defects or software bugs, which could harm our reputation and adversely affect our business.
Our products, including our platform (cloud, software and systems) and managed services, are highly technical and, when deployed, are critical to the operation of many networks. Our products have contained and are subject to defects, bugs or security vulnerabilities, which risks may be exacerbated as we continue to expand our cloud and software portfolio and include services from third-party partners. Some defects in our products may only be discovered after a product has been installed and used by customers and may in some cases only be detected under certain circumstances or after extended use. Any errors, bugs, defects or security vulnerabilities discovered in our products after commercial release could result in loss of revenue or delay in revenue recognition, loss of customers and increased service and warranty and retrofit costs, any of which could adversely affect our business, operating results and financial condition. In addition, we are subject to claims for security and data breach, product liability, tort or breach of warranty. Our contracts with customers contain provisions relating to warranty disclaimers and liability limitations, which may not be upheld. Defending a lawsuit, regardless of its merit, is costly and may divert management’s attention and adversely affect the market’s perception of us and our products. In addition, if our business liability insurance coverage proves inadequate or future coverage is unavailable on acceptable terms or at all, our business, operating results and financial condition could be adversely impacted.
If we are unable to ensure that our products interoperate properly and as required within our customers’ networks, our business will be harmed.
Our products must interoperate with our customers’ existing and planned networks, which often have varied and complex specifications, utilize multiple protocol standards, include software applications and customizations and products from multiple vendors and contain multiple generations of products that have been added over time. As a result, we must continually ensure that our products interoperate properly with these existing and planned networks. To meet these requirements, we must undertake development efforts, including test protocols, that require substantial capital investment and employee resources. We may not accomplish these development goals quickly or cost-effectively, if at all. If we fail to maintain interoperability, we may face substantially reduced demand for our products, which would reduce our revenue opportunities and market share. We rely upon interoperability arrangements with equipment and software vendors for the use or integration of their technology with our products. If these relationships fail, we may have to devote substantially more resources to developing alternative products and processes and our efforts may not be as effective as the combined solutions under our current arrangements. In some cases, these other vendors are either direct competitors or companies that have extensive relationships with our existing and potential customers and influence the purchasing decisions of those customers. Some of our competitors have stronger relationships with some of our interoperability partners, and as a result, our ability to have successful interoperability arrangements with these companies may be harmed, which in turn may harm our ability to successfully sell and market our products.
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Our estimates regarding warranty or product obligations are highly subjective. If our estimates change, the liability for warranty or product obligations may be increased, impacting future cost of revenue.
Our products are highly complex, and our product testing may not be adequate to detect all defects, errors, failures and quality issues. Accordingly, our estimates regarding future warranty or product obligations are highly subjective, and if our estimates change, the liability for warranty or product obligations may be increased, impacting future cost of revenue. Quality or performance problems for products covered under warranty could adversely impact our reputation and negatively affect our operating results and financial position. The development and production of new products with high complexity often involves problems with software, components and manufacturing methods. Any significant warranty or other product obligations due to reliability or quality issues arising from defects in software, faulty components or improper manufacturing methods could negatively impact our operating results and financial position due to costs associated with fixing software or hardware defects; high service and warranty expenses; high inventory obsolescence expense; delays in collecting accounts receivable; payment of liquidated damages for performance failures; and loss of customer goodwill and future sales.
Our business and operations depend on proprietary technologies, and our financial performance may suffer if we cannot protect and enforce our IP rights.
Our success and ability to compete depend on proprietary technology. We rely significantly upon patent, copyright, trademark, trade secret and other IP laws, IP registration rights and agreements with our employees, customers, partners, suppliers and other parties, to establish and maintain IP rights necessary for our business and operations. U.S. IP laws afford us only limited protection, and the laws of some foreign countries do not protect proprietary rights to the same extent or at all. Our patent applications may not result in issued patents, and our issued patents may not be enforceable. Our IP rights could be challenged, invalidated, infringed or circumvented, any of which could impair or harm our business and operations and be costly to defend. Our failure to adequately protect our IP rights could result in our competitors offering similar products, resulting in the loss of our competitive advantage and decreased sales.
We and our third-party providers may be unable to adequately prevent unauthorized third-party copying or use of our IP. For example, contractual provisions protecting our IP are subject to breach, and our IP is subject to reverse engineering and unlawful distribution. It may become more difficult to adequately protect our IP as we expand our reliance on third parties for the design, development and/or manufacture of our products. In addition, we may become subject to increased risks arising from or related to security breaches, data loss or theft of our data or our IP, and have greater difficulty protecting our IP as our work-from-anywhere workforce and work product become more distributed. Policing the unauthorized use and distribution of our IP is difficult and costly. Litigation, which could result in substantial costs, diversion of resources and harm to our business, may be necessary to enforce our IP rights, protect our trade secrets or determine the validity and scope of proprietary rights.
If we are unable to obtain third-party technology licenses needed for our products and platform solutions, our business and operations will be impaired, and our operating results could be adversely affected.
We increasingly rely on technology licensed from third parties for our products and platform solutions. We may not be able to secure or maintain necessary technology licenses from these third parties on commercially reasonable terms or at all. Third parties may also choose to not renew licenses with us, demand unreasonable license fees or cease to offer technologies that we require. The inability to obtain necessary third-party licenses or to secure reasonable license terms at a cost acceptable to us could harm the competitiveness of our products and solutions, result in lost revenue and adversely affect our operating results. For example, we may be forced to forego product features or platform offerings, including features and offerings we believe are critical to our strategy, accept substitute technology of lower quality or performance standards or incur higher costs, or the time-to-market of our products or product features could be delayed. Furthermore, our ability to utilize third-party technology may be disrupted by disputes over IP rights, including claims of IP infringement, which could prevent us from offering or selling the products that utilize the disputed technology and adversely affect our operating results.
Our use of open-source software could impose limitations on our ability to commercialize our products.
We incorporate open-source software into our products. The terms of many open-source software licenses have not been interpreted by the courts, and there is a risk that such licenses could be construed in a manner that could impose unanticipated conditions or restrictions on our ability to sell our products. In such event, we could be required to make our proprietary software generally available to third parties, including competitors, at no cost, to seek licenses from third parties in order to continue offering our products, to re-engineer our products or to discontinue the sale of our products in the event re-engineering cannot be accomplished on a timely basis or at all, any of which could adversely affect our revenue and operating expenses.
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Macroeconomic and Industry Risks
Adverse global economic, market and industry conditions, geopolitical issues and other conditions that impact our increasingly global operations could have a negative effect on our business, results of operations and financial condition and liquidity.
As a global company, our performance is affected by global economic, market and industry conditions as well as geopolitical issues and other conditions with global reach. In recent years, concerns about the global economic outlook, inflation and increased interest rates have adversely affected market and business conditions in general. Macroeconomic weakness and uncertainty make it more difficult for us to manage our operations and accurately forecast revenue, gross margin and operating expenses. Further, bank failures and other adverse developments that affect financial institutions, transactional counterparties, or other third parties, or concerns or rumors about these events, have led to market-wide liquidity problems.
Geopolitical issues, such as the Russian invasion of Ukraine, armed conflict in the Middle East, relations between the U.S. and China, tariff and trade policy changes, and increasing potential of conflict involving countries in Asia that are critical to our supply-chain operations, such as Taiwan and China, have resulted in increasing global tensions and create uncertainty for global commerce. In addition, inflation in the United States has affected businesses across many industries, including ours, by increasing the costs of labor, employee healthcare, components and freight and shipping, which may further constrain our customers’ or prospective customers’ budgets. To the extent there is a sustained general economic downturn, and our platform and services are perceived by customers or potential customers as costly, or too difficult to deploy or migrate to, our revenue may be disproportionately affected by delays or reductions in spending. Sustained or worsening of global economic conditions and geopolitical issues may increase our cost of doing business, materially disrupt our supply chain operations, cause our customers to reduce or delay spending and intensify pricing pressures. We cannot predict the timing, strength or duration of any economic slowdown, instability or recovery, generally or within any particular industry. If the economic conditions of the general economy or markets in which we operate worsen from present levels, demand for our products, and our business, financial condition and results of operations, could be adversely affected.
We face intense competition that could reduce our revenue and adversely affect our financial results.
The market for our products is highly competitive, and we expect competition from both established and new companies to increase. Our ability to compete successfully depends on a number of factors, including our ability to successfully develop new products and solutions that anticipate BSP and market requirements and changes in technology and industry standards; BSP acceptance and adoption of our products and solutions; our ability to differentiate our products from our competitors’ offerings based on performance, features, cost-effectiveness or other factors; our product capabilities to meet customer network requirements and preferences; and our success in marketing and selling our products and platform solutions.
Many of our current or potential competitors have longer operating histories, greater name recognition, broader product lines, larger customer bases and significantly greater financial, technical, sales, marketing and other resources than we do and are better positioned to acquire and offer complementary products and services. As the broadband access equipment market has undergone and continues to undergo consolidation, our competitors have merged, grown and been able to offer more comprehensive solutions than they individually had offered. Potential customers may also prefer to purchase from their existing suppliers rather than a new supplier, regardless of product performance or features, because the products that we and our competitors offer require a substantial investment of time and funds to qualify and install. The demand on network capacity due to remote workforces may attract new market entrants with competitive or substitutive products, which may lead to increased sales cycles, cause pricing pressure and impact adoption of our platform due to the broader availability of product offerings. Some of our competitors may offer substantial discounts or rebates to win or retain customers. If we are forced to reduce prices to retain existing customers or win new customers, we may be unable to sustain gross margin at desired levels or profitability. Competitive pressures could result in increased pricing pressure, reduced profit margin, increased sales and marketing expenses and failure to increase, or the loss of, market share, any of which could reduce our revenue and adversely affect our financial results.
Historically, our customer base has been concentrated, and the loss of any of our key customers may adversely impact our revenue and results of operations, and any delays in payment by a key customer could negatively impact our cash flows and working capital.
Although we have not had a greater-than-10%-of-revenue customer in the past three years, a large portion of our sales has been, and in the future may be, to a limited number of customers. Changes in the BSP market, such as financial difficulties, spending cuts or corporate consolidations that impact purchasing decisions by these customers have and may again negatively impact our revenue, and as a result, revenue from such customers may remain flat or decline. There are no assurances that the demand for our products will remain strong from our key customers, and any decrease or delay in purchases of any of our key customers, particularly if prolonged or sustained, or our inability to grow our sales with them, may have a material negative impact on our revenue and results of operations. As of December 31, 2023, two customers accounted for 19% and 14% of accounts receivable.
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In addition, some larger customers may demand discounts and rebates or desire to purchase their access systems and software from multiple providers. As a result of these factors, our future revenue opportunities may be limited, and we may face pricing pressures, which in turn could adversely impact our gross margin and our profitability. The loss of, reduction in, or pricing discounts associated with orders from any larger customer could significantly reduce our revenue and harm our business. Furthermore, delays in payment and/or extended payment terms from any of our larger customers could have a material negative impact on our cash flows and working capital to support our business operations.
Our industry is characterized by rapid technological advancements, and if we fail to develop new products or enhancements that meet changing BSP requirements, we could experience lower sales.
Our industry is characterized by rapid technological change, changing needs of BSPs, evolving industry standards and frequent introductions of new products and platform offerings. We invest significant amounts to pursue innovative technologies that we believe will be adopted by BSPs. For example, we have invested and plan to continue to invest resources in our platform offerings. In addition, on an ongoing basis, we expect to reposition our product and service offerings and introduce new offerings as we encounter rapidly changing BSP requirements and increasing competitive pressures. If we cannot increase sales of our new platform and services, keep pace with rapid technological developments to meet customer needs and compete with evolving standards or if the technologies we choose to invest in fail to meet customer needs or are not adopted by customers in the timeframes that we expect, our financial condition and results of operations would be adversely affected.
Developing our products is complex and involves uncertainties, including pricing risks for key materials, component shortages and limited suppliers. We may experience design, manufacturing, software development quality, support, marketing and other difficulties that could delay or prevent the development, introduction or marketing of new products and enhancements. If we fail to meet our development targets, demand for our products will decline. If we are unable to anticipate and develop new products or enhancements to our existing products on a timely and cost-effective basis, our products may become technologically obsolete more rapidly than anticipated over time, resulting in lower sales which would harm our business. Furthermore, the introduction of new or enhanced products also requires that we manage the transition from older products in accordance with customer requirements. If we fail to maintain compatibility requirements in our customers’ networks, demand for our products would decline, which would reduce our revenue opportunities and market share.
We use third-party development partners both for their key skills and to augment our employee developers. Using third-party development partners for our broadband platform and managed services allow us to accelerate development and leverage the third parties’ expertise, but increases our risks due to reduced direct control over the third party’s work. This product development approach may cause unforeseen issues in product design, as well as challenges arising from integration and support of third-party features in our products. In addition, our revenue based on the third parties’ product development work may take several years to cover our out-of-pocket expenses, if ever.
Our sales cycles can be long and unpredictable, and our sales efforts require considerable time and expense. As a result, our sales are difficult to predict and may vary substantially, which may cause our operating results to fluctuate significantly.
The timing of our revenue is difficult to predict. Our sales efforts often involve educating BSPs about the use and benefits of our platform (cloud, software and systems) and managed services. BSPs typically undertake a significant evaluation process, which frequently involves not only our platform and managed services, but also those of our competitors and results in a lengthy sales cycle. Sales cycles for larger customers are relatively longer and require considerably more time and expense. We spend substantial time, effort and money in our sales efforts without any assurance that our efforts will produce sales. In addition, product purchases are frequently subject to budget constraints, multiple approvals and unplanned administrative, processing and other delays. The timing of revenue related to sales of products and services that have installation requirements may be difficult to predict due to interdependencies that may be beyond our control, such as BSP testing and turn-up protocols or other vendors’ products, services or installations of equipment upon which our products and services rely. Such delays may result in fluctuations in our quarterly revenue. If sales expected from a specific customer for a particular quarter are not realized in that quarter or at all, we may not achieve our revenue forecasts, and our financial results would be adversely affected.
Our business depends upon the capital spending patterns and decisions of BSPs, and any decrease or delay in capital spending by BSPs due to the timing and availability of capital and other causes would reduce our revenue and harm our business.
Demand for our products depends on the magnitude and timing of capital spending by BSPs as they construct, expand, upgrade and maintain their access networks as well as BSPs’ adoption of our platform and managed services. Capital spending is cyclical in our industry, sporadic among individual BSPs and can change on short notice, which gives us little visibility into changes in spending behavior in any particular quarter. Capital spending for network infrastructure projects could be delayed or canceled in response to factors outside our control, such as reduced consumer spending, challenging capital markets or declining liquidity trends. BSP spending is also affected by reductions in budgets, including as a result of a general economic downturn, delays in purchasing cycles, access to government funding programs or capital markets, and seasonality and delays in capital allocation decisions. Historically, our customers may spend less or have less deployments in the first quarter due to
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pending annual budgets or, in certain regions, due to weather conditions that inhibit outside fiber deployment, resulting in weaker demand for our products in the first quarter. Softness in demand in any of our customer markets, including due to macroeconomic conditions beyond our control or uncertainties associated with regulatory reforms, has and could in the future lead to unexpected decline or slowdown in customer capital expenditures. Further, BSPs may pursue capital investment in network technologies other than those offered by us or may choose not to adopt our products and platform solutions in their networks. Reductions in capital expenditures by BSPs would have a material negative impact on our revenue and results of operations and slow our rate of revenue growth. As a consequence, our results for a particular period may be difficult to predict, and our prior results are not necessarily indicative of results in future periods.
Government-sponsored programs and U.S. federal government shutdowns could impact the timing and buying patterns of BSPs, which may cause fluctuations in our operating results.
We sell to BSPs, including U.S.-based IOCs, which rely significantly upon interstate and intrastate access charges and federal and state subsidies in the form of grants and other funding, such as the Federal Communications Commission’s, or FCC’s, Rural Digital Opportunity Fund, the CARES Act, Enhanced Alternative Connect America Cost Model, or the American Rescue Plan Act. The FCC and some states may change such payments and subsidies, which could reduce IOC revenue. Furthermore, many IOCs use or expect to use government-supported loan programs or grants, such as U.S. Department of Agriculture’s Rural Utility Service or the U.S. Department of Commerce National Telecommunications and Information Administration’s, or NTIA’s, Broadband Equity, Access and Deployment, or BEAD, Program loans and grants, to finance capital spending. These government-supported loan programs and grants generally include conditions such as deployment criteria, domestic preference provisions and other requirements that apply to the project and selected equipment as conditions for funding. For example, the U.S. government recently passed The Infrastructure Investment Jobs Act, which charged the NTIA with establishing the BEAD Program and ensuring that BEAD-funded infrastructure projects comply with the Buy America Domestic Content Procurement Preference, or Buy America Preference, of the Build America, Buy America Act, or BABA. In accordance with BABA, the U.S. Department of Commerce has proposed to issue a limited, general applicability, nonavailability waiver of the Buy America Preference to recipients of Federal financial assistance under the NTIA’s BEAD Program. Changes to the terms or administration of these programs, including uncertainty from government and administrative change, increasing focus on domestic requirements by the U.S. that may require re-assessment of compliance, potential funding limitations that impact our ability to meet program requirements or delays due to U.S. federal government shutdowns could reduce the ability of IOCs to access capital or secure funding under these programs to purchase our products and services and thus reduce our revenue opportunities. In addition, compliance with these requirements may significantly increase our record-keeping, accounting and production costs. As a result of these risks, the domestic content requirements may have a material adverse impact on our U.S. sales, business and results of operations. Customers may curtail purchases if they receive less funding than planned, are negatively impacted by federal government shutdowns or changes in government regulations and subsidies, or as funding winds down, any of which could have an adverse effect on our operating results and financial condition.
Government and Regulatory Risks
Actual or perceived failure to comply with applicable data privacy and security laws, regulations and standards could impact our business, operations, and expose us to increased liability.
Government authorities in the United States and around the world have implemented and are continuing to implement broader and more stringent laws and regulations concerning data protection. The interpretation and application of these data protection laws and regulations are often uncertain and changing, and it is possible that they may be interpreted and applied in a manner that is inconsistent with our data practices.
For example, in the U.S., certain states have adopted privacy and security laws and regulations which govern the privacy, processing and protection of personal information. Such laws and regulations will be subject to interpretation by various courts and other governmental authorities, thus creating potentially complex compliance issues for us and our future customers and strategic partners. For example, the California Consumer Privacy Act of 2018, or CCPA, went into effect on January 1, 2020. The CCPA creates individual privacy rights for California consumers and increases the privacy and security obligations of entities handling certain personal information. The CCPA provides for civil penalties for violations, as well as a private right of action for data breaches that has increased the likelihood of, and risks associated with data breach litigation. Further, the California Privacy Rights Act, or CPRA, generally went into effect on January 1, 2023, and significantly amends the CCPA. It imposes additional data protection obligations on covered businesses, including additional consumer rights processes, limitations on data uses, new audit requirements for higher risk data, and opt outs for certain uses of sensitive data. It also created a new California data protection agency authorized to issue substantive regulations and could result in increased privacy and information security enforcement. Additional compliance investment and potential business process changes may also be required. Similar laws have been passed in other states, and are continuing to be proposed at the state and federal level, reflecting a trend toward more stringent privacy legislation in the United States. Most of the new or proposed laws include restrictions on processing consumer information for targeted advertising, which could negatively affect our marketing cloud products. The enactment of such laws could have potentially conflicting requirements that would make compliance challenging.
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In the event that we are subject to or affected by the CCPA, the CPRA or other domestic privacy and data protection laws, any liability from failure to comply with the requirements of these laws could adversely affect our financial condition.
Furthermore, the Federal Trade Commission, or FTC, and many state Attorneys General continue to enforce federal and state consumer protection laws against companies for online collection, use, dissemination and security practices that appear to be unfair or deceptive. For example, according to the FTC, failing to take appropriate steps to keep consumers’ personal information secure can constitute unfair acts or practices in or affecting commerce in violation of Section 5(a) of the Federal Trade Commission Act. The FTC expects a company’s data security measures to be reasonable and appropriate in light of the sensitivity and volume of consumer information it holds, the size and complexity of its business, and the cost of available tools to improve security and reduce vulnerabilities.
The General Data Protection Regulation, or EU GDPR, adopted by the European Union, or EU, and the UK General Data Protection Regulation, or UK GDPR, adopted by the United Kingdom, or UK, (the EU GDPR and UK GDPR hereinafter referred to as the GDPR) and national data protection supplementing laws in these jurisdictions impose specific duties and requirements upon companies that are subject to their provisions and collect, process or control personal data of individuals, including a principle of accountability and the obligation to demonstrate compliance through policies, procedures, training and audit. Although we currently do not have material operations or business in the EU or the UK, we are in the process of expanding in these jurisdictions, and we have incurred and will continue to incur substantial costs in this respect. Furthermore, the GDPR imposes significant penalties for noncompliance which can amount to €20 million (for the EU GDPR) or £17.5 million (for the UK GDPR), or in the case of an undertaking, up to 4% of the total worldwide annual turnover of the preceding financial year, whichever is higher; thus, any non-compliance with the GDPR could result in a material adverse effect on our business, financial condition and results of operations.
The EU GDPR and UK GDPR regulate cross-border transfers of personal data out of the European Economic Area, or the EEA, and the UK. Case law from the Court of Justice of the European Union, or the CJEU, held that transfers must be assessed on a case-by-case basis and reliance on standard contractual clauses (a standard form of contract approved by the European Commission as an adequate mechanism for personal data transfers) may not be sufficient in all circumstances. On October 7, 2022, President Biden signed an Executive Order on Enhancing Safeguards for United States Intelligence Activities. This introduced new binding safeguards to address the concerns raised by the CJEU in relation to data transfers from the EEA to the United States and formed the basis of the new EU-US Data Privacy Framework, or DPF, which was released on December 13, 2022. The European Commission adopted its Adequacy Decision in relation to the DPF on July 10, 2023, rendering it effective as an EU GDPR transfer mechanism to U.S. entities self-certified under the DPF; further, on October 12, 2023, the UK Extension to the DPF came into effect (as approved by the UK Government), as a UK GDPR data transfer mechanism to U.S. entities self-certified under the UK Extension to the DPF. We currently rely on the standard contractual clauses and the UK International Data Transfer Agreement (or Addendum) to transfer personal data outside the EEA and the UK respectively, including to the U.S. The data transfers enforcement landscape and the DPF’s longer term stability remain uncertain and we expect the existing legal complexity and uncertainty regarding international personal data transfers to continue. As the regulatory guidance and enforcement landscape in relation to data transfers further develops, our business, operations and financial condition could be adversely affected. Our current contracts may not be sufficient, and we could suffer additional costs, complaints and/or regulatory investigations or fines. We may also have to stop using certain tools and vendors and make other operational changes. We have had to and will have to implement standard contractual clauses and/or the UK equivalent mechanism for intragroup, customer and vendor arrangements. Further, our customers may not use our services in a manner that is compliant with applicable data privacy laws and regulations and our services may not be competitive in certain markets.
We and/or our customers are also subject to evolving EU and UK privacy laws on cookies, tracking technologies, e-marketing and electronic communications. Recent European court and regulator decisions are driving increased attention to cookies and tracking technologies. If the trend of increasing enforcement by regulators of the strict approach to opt-in consent for all but essential use cases, as seen in recent guidance and decisions continues, this could lead to substantial costs, require significant systems changes, limit the effectiveness of marketing activities conducted on behalf of our customers, divert the attention of our technology personnel, adversely affect our margins, and subject us to additional liabilities. In addition, new security regulations, such as the EU’s Network and Information Security 2 Directive (NIS2) and the UK’s Telecommunications (Security) Act 2021 together with its implementing regulations impose further security obligations, including on electronic communications networks and services. We may be required to implement (and contractually commit to) additional security measures to remain a competitive vendor, as customers will need to ensure their vendors are able to meet the obligations that they are themselves subject to, or customers may choose different vendors due to our security measures. This could result in additional costs and require operational changes which could adversely affect our business, operations and financial condition.
In light of the complex and evolving nature of EU, EU Member State and UK privacy and security laws, there can be no assurances that we will be successful in our efforts to comply with such laws; violations of such laws could result in regulatory investigations, fines, orders to cease/change our use of technologies and/or our processing activities, enforcement notices and assessment notices (for a compulsory audit), as well as lead to civil claims including class actions, and reputational damage.
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Complying with new and changing laws could cause us to incur substantial costs in order to market and sell our cloud-based solutions in the U.S. and internationally, deter customers from adopting our cloud-based solutions or require us to redesign our platform in order to meet customer requirements related to such laws. Regulatory actions or claims involving our practices in the collection, storage, processing, use or disclosure of consumer information or other personal data, even if unfounded, could damage our reputation and adversely affect our operating results. The failure or perceived failure to comply may result in government or civil proceedings or actions against us, or could cause us to lose customers, which could have an adverse effect on our business.
If we fail to comply with evolving industry standards, sales of our products would be adversely affected.
Our products are subject to a significant number of domestic and international standards, which evolve as new technologies are developed and deployed. As we expand into new global markets, we are likely to encounter additional standards. Our products must comply with these standards in order to be widely marketable. In some cases, we are required to obtain certifications or authorizations before our products can be introduced, marketed or sold in new markets or to new customers. For example, our ability to maintain Operations System Modification for Intelligent Network Elements certification for our products will affect our ongoing ability to continue to sell our products to large BSPs. In addition, our ability to expand our international operations may be limited by standards in countries or may require us to redesign our products or develop new products to meet local standards. We may not be able to design our products to comply with local requirements, which would impede or prevent our ability to grow our business in those locations. Moreover, as we expand our business and operations globally, we must increase investments to maintain compliance with evolving standards across all of our markets. The costs of complying with evolving standards or failure to obtain timely authorizations or certification could prevent us from selling our products where these standards or regulations apply, which would result in lower revenue and lost market share.
Our failure or the failure of our manufacturers to comply with environmental and other legal regulations could adversely impact our results of operations.
The manufacture, assembly and testing of our products may require the use and disposal of hazardous materials that are subject to environmental, health and safety regulations, or materials subject to laws restricting the use of conflict minerals. We substantially depend upon our third-party manufacturers to comply with these requirements. Any failure by us or our third-party manufacturers to comply with these requirements could result in regulatory penalties, legal claims or disruption of production of our products. In addition, any failure to properly manage the use, transportation, emission, discharge, storage, recycling or disposal of hazardous materials could subject us to increased costs or liabilities. Existing and future environmental regulations and other legal requirements may restrict our use of certain materials to manufacture, assemble and test products. Any of these consequences could adversely impact our results of operations by increasing our expenses and/or requiring us to alter our manufacturing processes.
We are subject to governmental export and import controls that could subject us to liability or impair our ability to compete in additional international markets.
Our products are subject to U.S. export and trade controls and restrictions. International shipments of certain of our products may require export licenses or are subject to additional export requirements. In addition, the import laws of other countries may limit our ability to distribute our products, or our customers’ ability to buy and use our products, in those countries. Changes in our products or changes in export and import regulations or duties may create delays in the introduction of our products in international markets, prevent our customers with international operations from deploying our products or, in some cases, prevent the export or import of our products to certain countries altogether. Any change in export or import regulations, duties or related legislation, shift in approach to the enforcement or scope of existing regulations, or change in the countries, persons or technologies targeted by such regulations, could negatively impact our ability to sell, profitably or at all, our products to existing or potential international customers.
Regulatory and physical impacts of climate change and other natural events may affect our customers and our manufacturers, resulting in adverse effects on our operating results.
As emissions of greenhouse gases continue to alter the composition of the atmosphere, affecting large-scale weather patterns and the global climate, any new regulation of greenhouse gas emissions may result in additional costs to our customers and our manufacturers. In addition, the physical impacts of climate change and other natural events, including changes in weather patterns, drought, rising ocean and temperature levels, earthquakes and tsunamis may impact our customers, suppliers and manufacturers and our operations. These potential physical effects may adversely affect our revenue, costs, production and delivery schedules, and cause harm to our results of operations and financial condition.
Our customers are subject to government regulation, and changes in current or future laws or regulations that negatively impact our customers could harm our business.
Many of our customers are subject to state and federal regulation of their businesses, and adoption of regulations that affect providers of broadband Internet access services could impede the penetration of our customers into certain markets. For
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example, the FCC has jurisdiction over many of our U.S. customers, and FCC regulatory policies that create disincentives for investment in access network infrastructure or impact the competitive environment in which our customers operate may harm our business. Moreover, various international regulatory bodies have jurisdiction over certain of our customers outside the U.S. Changes in any of these standards, laws and regulations, or judgments in favor of plaintiffs in lawsuits against BSPs based on changed standards, laws and regulations could adversely affect the development of broadband networks and services. This, in turn, could directly or indirectly adversely impact the industries in which our customers operate.
Risks Related to Ownership of Our Common Stock and Other Risks
Our stock price may continue to be volatile, and the value of an investment in our common stock may decline.
The trading price of our common stock has been, and is likely to continue to be, volatile, which means that it could decline substantially within a short period of time and could fluctuate widely in response to various factors, some of which are beyond our control. These factors include those discussed above and others such as quarterly variations in our results of operations or those of our competitors; failure to meet any guidance that we have previously provided regarding our anticipated results; changes in earnings estimates or recommendations by securities analysts; failure to meet securities analysts’ estimates; announcements by us or our competitors of new products, significant contracts, commercial relationships, acquisitions or capital commitments; developments with respect to IP rights; our ability to develop and market new and enhanced products on a timely basis; our commencement of, or involvement in, litigation and developments relating to such litigation; changes in governmental regulations; and a slowdown in the communications industry or the general economy.
The stock market in general, and the market for technology companies in particular, has experienced extreme price and volume fluctuations that have often been unrelated or disproportionate to the operating performance of those companies. Broad market and industry factors may seriously affect the market price and volatility of our common stock, regardless of our actual operating performance. Historically, following periods of volatility in the market price of a company’s securities, there is increased risk that stockholders may initiate securities class action litigation against the company. Such litigation, if instituted against us, could result in substantial costs and a diversion of our management’s attention and resources.
Provisions in our charter documents and under Delaware law could discourage a takeover that stockholders may consider favorable and may lead to entrenchment of our management and Board of Directors.
Our amended and restated certificate of incorporation and amended and restated bylaws contain provisions that could have the effect of delaying or preventing changes in control or changes in our management or our Board of Directors. These provisions include: (1) a classified Board of Directors with three-year staggered terms, which may delay the ability of stockholders to change the membership of a majority of our Board of Directors; (2) no cumulative voting in the election of directors, which limits the ability of minority stockholders to elect director candidates; (3) the exclusive right of our Board of Directors to elect a director to fill a vacancy created by the expansion of the Board of Directors or the resignation, death or removal of a director, which prevents stockholders from being able to fill vacancies on our Board of Directors; (4) the ability of our Board of Directors to issue shares of preferred stock and to determine the price and other terms of those shares, including preferences and voting rights, without stockholder approval, which could be used to significantly dilute the ownership of a hostile acquirer; (5) a prohibition on stockholder action by written consent, which forces stockholder action to be taken at an annual or special meeting of our stockholders; (6) the requirement that a special meeting of stockholders may be called only by the chairman of the Board of Directors, the chief executive officer or the Board of Directors, which may delay the ability of our stockholders to force consideration of a proposal or to take action, including the removal of directors; and (7) advance notice procedures that stockholders must comply with in order to nominate candidates to our Board of Directors or to propose matters to be acted upon at a stockholders’ meeting, which may discourage or deter a potential acquirer from conducting a solicitation of proxies to elect the acquirer’s own slate of directors or otherwise attempting to obtain control of us. We are also subject to certain anti-takeover provisions under Delaware law, which prohibits a corporation, in general, from engaging in a business combination with any holder of 15% or more of its capital stock unless the holder has held the stock for three years or, among other things, the Board of Directors has approved the transaction.
We may need additional capital in the future to finance our business.
While our working capital needs to support our business operations and growth have been funded from operating cash flows in the near term, we may need additional capital if our current plans and assumptions change. If our financial position deteriorates, we may not be able to secure a source of financing to support our working capital needs on acceptable terms or at all. If future financings involve the issuance of equity securities, our then-existing stockholders will suffer dilution. If we raise debt financing, we may be subject to restrictive covenants that limit our ability to conduct our business. If we are unable to sustain positive operating income and cash flows from operations, our liquidity, results of operations and financial condition may be adversely affected. Furthermore, if we are unable to generate sufficient cash flows to support our operational needs, we may need to cease our common stock repurchase program or seek additional sources of liquidity, including borrowings, to support our working capital needs, even if we believe we have generated sufficient cash flows to support our operational needs. There is no assurance that any other sources of liquidity may be available to us on acceptable terms or at all. If we are unable to generate
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sufficient cash flows or obtain other sources of liquidity, we will be forced to limit our development activities, reduce our investment in growth initiatives and institute cost-cutting measures, all of which would adversely impact our business and growth.
We do not currently intend to pay dividends on our common stock and, consequently, our stockholders’ ability to achieve a return on their investment will depend on appreciation in the price of our common stock.
We do not currently intend to pay a cash dividend on our common stock for the foreseeable future. We currently intend to invest our future earnings, if any, to fund our growth. Therefore, our stockholders are not likely to receive any dividends on our common stock for the foreseeable future.
Our failure to adequately address and resolve risks and uncertainties associated with acquisitions could have a material adverse impact on our financial condition and results of operations.
We may acquire businesses, products or technologies to expand our product offerings and capabilities, customer base and business. We have evaluated and expect to continue to evaluate a wide array of potential strategic transactions. Such investments may involve significant risks and uncertainties, including distraction of management from current operations, unanticipated costs, and legal and regulatory challenges, all of which could have a material adverse impact on our financial condition and results of operations. In addition, the anticipated benefit of any acquisition may never materialize or the process of integrating acquired businesses, products or technologies may create unforeseen operating difficulties and expenditures.
We cannot guarantee that our stock repurchase program will be utilized to the full value approved or that it will enhance long-term stockholder value. Repurchases we consummate could increase the volatility of the price of our common stock and could have a negative impact on our available cash balance.
We have a common stock repurchase program of which $113.6 million was available as of December 31, 2023. Under the repurchase program, repurchases can be made from time to time using a variety of methods, which may include open market purchases, privately negotiated transactions or otherwise, all in accordance with the rules of the SEC and other applicable legal requirements. The specific timing, price and size of the purchases will depend on prevailing stock prices, general economic and market conditions, and other considerations consistent with our capital allocation strategy. Stock repurchases could have an impact on our common stock trading prices, increase the volatility of the price of our common stock, or reduce our available cash balance such that we will be required to seek financing to support our operations. The repurchase program does not obligate us to acquire a particular amount of common stock, and the repurchase program may be suspended or discontinued at any time at our discretion, which may result in a decrease in the trading prices of our common stock. Even if our share repurchase program is fully implemented, it may not enhance long-term stockholder value.
General Risks
As a public company, we are subject to significant accounting, legal and regulatory requirements; our failure to comply with these requirements may adversely affect our operating results and financial condition.
We are subject to significant accounting, legal and regulatory requirements, including requirements and rules under the Sarbanes-Oxley Act, or SOX, and the Dodd-Frank Wall Street Reform and Consumer Protection Act, or Dodd-Frank, among other rules and regulations implemented by the SEC, as well as listing requirements of the New York Stock Exchange, or NYSE. We incur significant accounting, legal and other expenses and must invest substantial time and resources to comply with public company reporting and compliance requirements, including costs to ensure we have adequate internal controls over accounting and financial reporting, proper documentation and testing procedures among other requirements. We cannot be certain that the actions we have taken to implement internal controls over financial reporting will be sufficient. We have in the past discovered, and may in the future discover, areas of our internal financial and accounting controls and procedures that need improvement, particularly as we enhance, automate and improve functionality of our processes and internal applications. New laws and regulations as well as changes to existing laws and regulations affecting public companies would likely result in increased costs to us as we respond to their requirements. We continue to invest resources to comply with evolving laws and regulations, and this investment may result in increased general and administrative expense.
If we fail to maintain proper and effective internal controls, our ability to produce accurate financial statements on a timely basis could be impaired, which would adversely affect our operating results and our stock price.
Our management is responsible for establishing and maintaining adequate internal control over financial reporting to provide reasonable assurance regarding the reliability of our financial reporting and the preparation of financial statements in accordance with U.S. generally accepted accounting principles. Our management does not expect that our internal control over financial reporting will prevent or detect all error and all fraud. A control system, no matter how well designed and operated, can provide only reasonable, not absolute, assurance that the control system’s objectives will be met. Because of the inherent limitations in all control systems, no evaluation of controls can provide absolute assurance that misstatements due to error or fraud will not occur or that all control issues and instances of fraud, if any, within our company will have been detected. If we
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are unable to produce accurate financial statements on a timely basis, investors could lose confidence in the reliability of our financial statements, which could cause the market price of our common stock to decline and make it more difficult for us to finance our operations and growth.
ITEM 1B.    Unresolved Staff Comments
None.
ITEM 1C.    Cybersecurity
Cybersecurity Risk Management and Strategy
We have developed and implemented a cybersecurity risk management program intended to protect the confidentiality, integrity and availability of our critical systems and information.
We design and assess our program based on the National Institute of Standards and Technology Cybersecurity Framework, or NIST CSF, and the MITRE ATT&CK® Framework. This does not imply that we meet any particular technical standards, specifications or requirements, only that we use the NIST CSF and the MITRE ATT&CK® as a guide to help us identify, assess and manage cybersecurity risks relevant to our business.
Our cybersecurity risk management program is integrated into our overall enterprise risk management program and shares common methodologies, reporting channels and governance processes that apply across the enterprise risk management program to other legal, compliance, strategic, operational, and financial risk areas.
Key aspects of our cybersecurity risk management program include the following:
risk assessments designed to help identify material cybersecurity risks to our critical systems, information, products, services and our broader enterprise IT environment;
a security team principally responsible for managing (1) our cybersecurity risk assessment processes, (2) our security controls and (3) our response to cybersecurity incidents;
the use of external service providers, where appropriate, to assess, test or otherwise assist with aspects of our security controls and processes;
cybersecurity awareness training of our employees, incident response personnel and senior management;
a cybersecurity incident response plan that includes procedures for responding to cybersecurity incidents; and
a third-party risk management process for key service providers, suppliers and vendors.
We have not identified risks from known cybersecurity threats, including as a result of any prior cybersecurity incidents, that have materially affected us, including our operations, business strategy, results of operations or financial condition. We face risks from certain cybersecurity threats that, if realized, are reasonably likely to materially affect us, including our operations, business strategy, results of operations, or financial condition. See Item 1A “Risk Factors – Cyberattacks or other security incidents that disrupt our operations or compromise data, may expose us to liability, harm our reputation or otherwise adversely affect our business.”
Cybersecurity Governance
Our Board considers cybersecurity risk as part of its risk oversight function and has delegated to the Cybersecurity Committee (the “Committee”) since its formation in 2017 oversight of business continuity, cybersecurity and other information technology risks. The Committee oversees management’s implementation of our cybersecurity risk management program.
The Committee receives quarterly reports from management on our cybersecurity risks. In addition, management updates the Committee, as necessary, regarding any significant cybersecurity incidents.
The Committee reports to the full Board regarding its activities, including those related to cybersecurity. The full Board also receives briefings from management on our cyber risk management program. Board members receive presentations on cybersecurity topics from our management team, internal security staff or external experts as part of the Board’s continuing education on topics that impact public companies.
Our Chief Commercial Operations Officer and Chief Product Officer are primarily responsible for assessing and managing our material risks from cybersecurity threats and supervise both our internal cybersecurity personnel and our retained external cybersecurity consultants. They stay informed about and monitory the prevention, detection, mitigation and remediation of key cybersecurity risks and incidents through various means, which may include briefings with internal and external security team
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members, threat intelligence and other information obtained from public or private sources and alerts and reports produced by security tools deployed in the IT environment.
Our cybersecurity management team includes our corporate vice president of information technology, who leads the operational teams responsible for enterprise security, data governance and enterprise incident response, and global operations, and our senior vice president of cloud and engineering operations, who leads the operational teams responsible for product and cloud security, data governance and product security incident response. Our operational cybersecurity teams are comprised of members with decades of collective experience in IT security systems, tooling, operations, and governance, and hold various IT security industry certifications and have received specialized cybersecurity training.
ITEM 2.    Properties
We currently lease our corporate headquarters in San Jose, California. In addition to our headquarters site, we lease additional office space in China, India and the United States. We believe that our facilities are in good condition and are generally suitable to meet our needs for the foreseeable future. We believe that prior to expiration of our current office space leases that we can renew or obtain suitable lease space on commercially reasonable terms for our business needs. In addition, we may continue to seek additional space as needed, and we believe this space will be available on commercially reasonable terms.
ITEM 3.    Legal Proceedings
From time to time, we are involved in various legal proceedings arising from the normal course of business. We are not currently a party to any legal proceedings that, if determined adversely to us, in our opinion, are currently expected to individually or in the aggregate have a material adverse effect on our business, operating results or financial condition taken as a whole.
ITEM 4.    Mine Safety Disclosures
Not applicable.
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PART II
ITEM 5.    Market for Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities
Comparative Stock Prices
Our common stock has been trading on the New York Stock Exchange, under the trading symbol “CALX” since our initial public offering on March 24, 2010. Prior to this time, there was no public market for our common stock.
Number of Common Stockholders
As of February 9, 2024, the approximate number of holders of our common stock was 1,151 (not including beneficial owners of stock held in street name).
Securities Authorized for Issuance under Equity Compensation Plans
The information required by this item is incorporated by reference to our 2023 Annual Report to Stockholders, which includes our definitive Proxy Statement for our 2024 Annual Meeting of Stockholders.
Dividends
We have never declared or paid a cash dividend on our common stock, and we do not currently intend to pay any cash dividends on our common stock in the foreseeable future.
Recent Sales of Unregistered Securities
None.
Issuer Purchases of Equity Securities
We maintain a common stock repurchase program. In November 2023, our Board of Directors authorized a $100 million increase to this program. Our repurchase activity for the three months ended December 31, 2023 was as follows (in thousands, except per share amounts):
Total Number of Shares RepurchasedAverage Price Paid Per ShareTotal Number of Shares Repurchased as Part of Publicly Announced Plans or ProgramsApproximate Dollar Value of Shares That May Yet Be Purchased Under the Plans or Programs
October 1 to October 31485 $35.07 485 $40,587 
November 1 to November 30772 34.96 772 113,603 
December 1 to December 31— — — 113,603 
1,257 1,257 
Performance Graph
The following graph shows a comparison of the cumulative total stockholder return on our common stock with the cumulative total returns of the NYSE Composite Index, Russell 2000 Index and the S&P 500 Communications Equipment Index. The graph tracks the performance of a $100 investment in our common stock and in each of the indexes during the last five fiscal years ended December 31, 2023. Data for the Russell 2000 Index and S&P 500 Communications Equipment assume reinvestment of dividends. Stockholder returns over the indicated period are based on historical data and should not be considered indicative of future stockholder returns.
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https://cdn.kscope.io/3867b20d030634c5e0761750d835da4d-Graph.jpg
This performance graph shall not be deemed “soliciting material” or to be “filed” with the SEC for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities under that Section, and shall not be deemed to be incorporated by reference into any filing of Calix, Inc. under the Securities Act of 1933, as amended.
ITEM 6.    [Reserved]

ITEM 7.    Management’s Discussion and Analysis of Financial Condition and Results of Operations
The Management’s Discussion and Analysis of Financial Condition and Results of Operations contains forward-looking statements regarding future events and our future results that are subject to the safe harbors created under the Securities Act of 1933 (the “Securities Act”) and the Securities Exchange Act of 1934 (the “Exchange Act”). All statements other than statements of historical facts are statements that could be deemed forward-looking statements. These statements are based on current expectations, estimates, forecasts and projections about the industry in which we operate and the beliefs and assumptions of our management. In some cases, forward-looking statements can be identified by the use of words such as “believe,” “could,”expect,” “may,” “estimate,” “continue,” “anticipate,” “intend,” “should,” “plan,” “predict,” “will,” “would,” “project,” “potential,” or the negative thereof or other comparable terminology. In addition, any statements that refer to projections of our future financial performance, our anticipated growth and trends in our business and industry and other characterizations of future events or circumstances are forward-looking statements. Readers are cautioned that these forward-looking statements are only predictions and are subject to risks, uncertainties and assumptions that are difficult to predict, including those identified in the Risk Factors discussed in Item 1A, in the discussion below, as well as in other sections of this Annual Report on Form 10-K. Therefore, actual results may differ materially and adversely from those expressed in any forward-looking statements. All forward-looking statements and reasons why results may differ included in this report are made as of the date hereof, and we assume no obligation to update these forward-looking statements or reasons why actual results might differ.
Overview
We develop, market and sell our platform (cloud, software and systems) and managed services that enable service providers of all types and sizes to innovate and transform their businesses. For our customers to successfully transform their businesses into the innovative BSPs of the future, they require actionable data for critical business functions such as network operations, customer support and marketing. However, this data is often trapped in disparate systems or departmental silos. Our platform, which includes Calix Cloud, Revenue EDGE and Intelligent Access EDGE, gathers, analyzes and applies machine learning to deliver real-time insights seamlessly to each key business function. Our customers utilize these insights to simplify network operations, marketing and customer support and deliver a growing portfolio of SmartLife managed services and experiences that excite their subscribers. This enables BSPs to grow their brand through increased subscriber acquisition, loyalty and revenue and to reduce their operating costs, creating value for their businesses and the communities they serve.
We market our platform and managed services to communication service providers globally through our direct sales force as well as select resellers. Our customers range from smaller, regional service providers to some of the world’s largest service
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providers. Customers are defined into small (less than 250,000 subscribers), medium (250,000 to 2.5 million subscribers) or large (greater than 2.5 million subscribers). We have approximately 1,600 active customers that have deployed passive optical, Active Ethernet or point-to-point Ethernet fiber access networks or our subscriber premise systems.
Our revenue and potential revenue growth will depend on our ability to develop, market and sell our platform and managed services to strategically aligned customers of all types such as WISPs, fiber overbuilders, cable MSOs, municipalities and electric cooperatives in the United States and internationally. Our growth is also highly dependent on the speed and willingness of customers to adopt our platform and managed services.
Revenue fluctuations result from many factors, including, but not limited to: increases or decreases in customer orders for our products and services, market, financial or other factors that may delay or materially impact customer purchasing decisions, non-availability of products due to supply chain challenges, including component and labor shortages and increasing lead times as well as disruptions as a result of pandemics or natural disasters, contractual terms with customers that result in delayed revenue recognition and varying budget cycles and seasonal buying patterns of our customers. More specifically, our customers have in the past spent less in the first quarter as they are finalizing their annual budgets, and in certain regions, customers are challenged by winter weather conditions that inhibit fiber deployment in outside infrastructure. In recent years, as our revenue from our large customers decreased, we have experienced less year-end volatility due to capital budgetary spending or freezing. This, combined with an increase in recurring revenue, has resulted in smaller seasonal fluctuations, and we expect this trend to continue. Our revenue is also dependent upon our customers’ success in growing their subscribers, timing of purchases, capital expenditure plans and decisions to upgrade their networks or adopt new technologies, including adoption of our software and cloud platform solutions, as well as our ability to grow our customer base.
Cost of revenue is strongly correlated to revenue and tends to fluctuate due to all of the above factors that may cause revenue fluctuations. Factors that have impacted our cost of revenue, or that we expect may impact cost of revenue in future periods, also include: changes in the mix of products delivered, customer location and regional mix, changes in the cost of our inventory, investments to support expansion of cloud and customer support offerings as well as our customer success organization, changes in product warranty, incurrence of retrofit costs, amortization of intangibles, support fees for silicon-related development work for our products, changes in trade policies, allowances for obligations to our suppliers and inventory write-downs. In addition, we periodically elect to ship by air versus by ocean in order to meet delivery commitments to our customers, which is more costly. Cost of revenue also includes fixed expenses related to our internal operations, which could increase our cost of revenue as a percentage of revenue if our revenue declines.
Our gross profit and gross margin fluctuate based on timing of factors such as changes in customer mix and changes in the mix of products demanded and sold (and any related write-downs of existing inventory or accrual for supplier commitments) and have in the past been and may be negatively impacted by increases in mix of revenue from channel sales rather than direct sales or other unfavorable customer or product mix, shipment volumes and any related volume discounts, changes in our product and services costs, pricing decreases or discounts, new product introductions or upgrades to existing products, customer rebates and incentive programs due to competitive pressure or materials shortages, supply constraints, investments to support expansion of cloud and customer support offerings, tariffs or unfavorable changes in trade policies.
Our operating expenses fluctuate based on the following factors among others: changes in headcount and personnel costs, which comprise a significant portion of our operating expenses; variable compensation due to fluctuations in shipment volumes or level of achievement against performance targets; timing of research and development expenses, including investments in innovative solutions and new customer segments, prototype builds and outsourced development resources; investments in marketing programs; asset write-offs; investments in our business and information technology infrastructure; and fluctuations in stock-based compensation expenses due to timing of equity grants or other factors affecting vesting.
Further, as a result of factors contributing to the fluctuations described above among other factors, many of which are outside our control, our quarterly operating results fluctuate from period to period. Comparing our operating results on a period-to-period basis may not be meaningful, and you should not rely on our past results as an indication of our future performance.
Critical Accounting Policies and Estimates
Our financial statements are prepared in accordance with U.S. generally accepted accounting principles. These accounting principles require us to make certain estimates and judgments that can affect the reported amounts of assets and liabilities as of the date of the financial statements, as well as the reported amounts of revenue, costs and expenses during the periods presented. We base our estimates, assumptions and judgments on historical experience and on various other factors that are believed to be reasonable under the circumstances. To the extent there are material differences between these estimates and actual results, our financial statements may be affected. We evaluate our estimates, assumptions and judgments on an ongoing basis.
We believe the following critical accounting policies affect our significant judgments and estimates used in the preparation of our financial statements.
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Revenue Recognition
Revenue is recognized when a performance obligation is satisfied, which occurs when control of the promised goods or services is transferred to the customer, in an amount that reflects the consideration we expect to be entitled to in exchange for those goods or services. Revenue from sales of access and premises systems is recognized when control is transferred to the customer, which is generally when the products are shipped. Revenue from software platform licenses, which provides the customer with a right to use the software as it exists, is generally recognized upfront when product is made available to the customer. Revenue from cloud-based software subscriptions, customer support, maintenance, extended warranty subscriptions and managed services is generally recognized ratably over the contract term. Revenue from professional services and training is recognized as the services are delivered.
A performance obligation is a promise in a contract to transfer a distinct good or service to the customer and is the unit of account. A contract’s transaction price is allocated to each distinct performance obligation and recognized as revenue when, or as, the performance obligation is satisfied. Our hardware products contain both software and non-software components that function together to deliver the products’ essential functionality and therefore constitutes a single performance obligation as the promise to transfer the individual software and non-software components is not separately identifiable and, therefore, not distinct. Cloud-based software subscriptions can include multi-year agreements with a fixed annual fee for a minimum committed usage level. To the extent that minimum committed usage level each year varies, we have concluded that each year represents a distinct stand-ready performance obligation and the transaction price allocated to each performance obligation is recognized as revenue ratably over each annual period. Our contracts may include multiple performance obligations. For such arrangements, we allocate the contract’s transaction price to each performance obligation using the relative stand-alone selling price of each distinct good or service in the contract. We generally determine stand-alone selling prices based on the prices charged to customers or our best estimate of stand-alone selling price. Our estimate of stand-alone selling price is established considering multiple factors including, but not limited to, geographies, market conditions, competitive landscape, internal costs, gross margin objectives, characteristics of targeted customers and pricing practices. The determination of estimated stand-alone selling price is made through consultation with and formal approval by management, taking into consideration the go-to-market strategy.
Inventory Valuation and Supplier Purchase Commitments
Inventory, which primarily consists of finished goods purchased from CMs or ODMs, is stated at the lower of cost (determined by the first-in, first-out method) and net realizable value. Inbound shipping costs and tariffs are included in the cost of inventory. In addition, from time to time, we procure component inventory primarily as a result of manufacturing discontinuation of critical components by suppliers. Furthermore, post the global pandemic-induced supply chain challenges, we have purchased, and may continue to purchase, excess components from our suppliers and consigned back to our suppliers to be consumed on future finish good builds. We regularly monitor inventory on-hand and record write-downs for excess and obsolete inventory based on our estimate of demand for our products, potential obsolescence of technology, product life cycles and whether pricing trends or forecasts indicate that the carrying value of inventory exceeds our estimated selling price. We also evaluate our supplier purchase commitments, which remain elevated due to extended lead-times created by pandemic-induced supply-chain challenges, and record a liability for excess and obsolete components based on our estimated demand of our products, potential obsolescence of technology and product life cycles. For example, during the fourth quarter of 2023, we wrote down excess and obsolete inventory and accrued a liability for components at suppliers primarily related to the wind down of our legacy product family that existed before our shift to an all-platform model. These factors are impacted by market and economic conditions, competitive dynamics, technology changes and new product introductions and require estimates that may include elements that are uncertain. Actual demand may differ from forecasted demand and may have a material effect on gross profit. If inventory is written down, a new cost basis is established that cannot be increased in future periods. The sale of previously reserved inventory has not had a material impact on our gross margin.
Recent Accounting Pronouncements Not Yet Adopted
There have been no additional accounting pronouncements or changes in accounting pronouncements that are significant or potentially significant to us.
Results of Operations for Years Ended December 31, 2023 and 2022
Revenue
The following table sets forth our revenue (dollars in thousands):
Years Ended December 31,2023 vs 2022 Change
20232022$%
Revenue$1,039,593 $867,827 $171,766 20 %
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Our revenue increased by $171.8 million, or 20%, during 2023 compared with 2022. The increase in revenue was primarily due to strength in shipments to one of our large customers, continued shipments throughout 2023 from a new medium-sized BSP customer that we added in the third quarter of 2022 and higher revenue from our growing base of small and medium BSP customers as they expand with our platform and managed services to simplify their operations, excite their subscribers with better experiences and grow their value to the communities they serve.
Our revenue is principally derived in the United States. Revenue generated in the United States represented 91% of revenue in 2023 and 91% in 2022. Our primary focus has been, and in the near term will continue to be, the United States and Canada given our large, direct sales and marketing presence and the amount of government stimulus being invested into underserved and not-served areas of these countries. In 2022, we introduced our platform to the United Kingdom. Over time, we expect to move to additional high average-revenue-per-user markets with our platform.
No customer accounted for more than 10% of our revenue for 2023, 2022 or 2021. See Note 11 “Revenue from Contracts with Customers” to the Consolidated Financial Statements included in this Annual Report on Form 10-K for more details on concentration of revenue for the years presented.
Gross Profit and Gross Margin
The following table sets forth our gross profit and gross margin (dollars in thousands):
Years Ended December 31,2023 vs 2022 Change
20232022
$
%
Gross profit$518,316 $435,428 $82,888 19 %
Gross margin49.9 %50.2 %
Gross profit increased by $82.9 million to $518.3 million during 2023 from $435.4 million during 2022. Gross margin decreased to 49.9% during 2023 from 50.2% during 2022. The decrease in gross margin of 30 basis points, compared to the corresponding period in 2022, was mainly due to charges of $28.7 million recorded in the fourth quarter of 2023 as we wrote down obsolete inventory and accrued a liability for components at suppliers primarily associated with our legacy product family that existed before our shift to an all-platform model. During 2023, customers moved to our platform model at a faster rate than originally anticipated, leaving us with excess finished goods and related components at suppliers. This decrease was partially offset by increased contributions from our platform and managed services, a shift in product mix and the sell through of a lower amount of excessively priced components acquired in the secondary market during the supply-chain disruption.
Operating Expenses
Sales and Marketing Expenses
Sales and marketing expenses consist of personnel costs, employee sales commissions, marketing programs and events, software tools and travel-related expenses. The following table sets forth our sales and marketing expenses (dollars in thousands):
Years Ended December 31,2023 vs 2022 Change
20232022$%
Sales and marketing$214,564 $174,549 $40,015 23 %
Percent of revenue21 %20 %
Sales and marketing expenses increased by $40.0 million during 2023 compared to 2022 primarily due to increases in personnel expenses of $29.4 million mainly related to increased sales headcount and higher sales incentive compensation corresponding to our increased revenue, stock-based compensation of $5.0 million and travel expenses of $2.2 million.
We expect our investments in sales and marketing will increase in absolute dollars as we extend our market reach and grow our business in support of our key strategic initiatives.
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Research and Development Expenses
Research and development expenses include personnel costs, outside contractor and consulting services, depreciation on lab equipment, costs of prototypes and overhead allocations. The following table sets forth our research and development expenses (dollars in thousands):
Years Ended December 31,2023 vs 2022 Change
20232022$%
Research and development$177,772 $131,994 $45,778 35 %
Percent of revenue17 %15 %
Percent of gross profit34 %30 %
The increase in research and development expenses of $45.8 million during 2023 compared with 2022 was mainly due to increases in personnel expenses of $31.7 million driven by increased headcount, stock-based compensation of $4.8 million, depreciation and amortization of $3.2 million, prototypes and test equipment expenses of $2.9 million and outside services of $1.2 million.
We expect our investments in research and development to increase in absolute dollars as we seek to expand the functionality and capabilities of our platforms.
General and Administrative Expenses
General and administrative expenses consist primarily of personnel costs related to our executive, finance, human resources, information technology and legal organizations, outside consulting services, insurance, facilities and fees for professional services. Professional services consist of outside audit, legal, accounting and tax services. The following table sets forth our general and administrative expenses (dollars in thousands):
Years Ended December 31,2023 vs 2022 Change
20232022$%
General and administrative$100,395 $76,275 $24,120 32 %
Percent of revenue10 %%
The increase in general and administrative expenses of $24.1 million in 2023 compared to 2022 was mainly due to increases in personnel expenses of $10.8 million driven by increased headcount, stock-based compensation of $8.0 million, litigation settlement of $3.2 million and outside services of $1.0 million.
We expect our general and administrative investments to increase in absolute dollars as we support the business.
Interest and Other Income, Net
The following table sets forth our interest and other income, net (dollars in thousands):
Years Ended December 31,2023 vs 2022 Change
20232022$%
Interest and other income, net$9,172 $1,432 $7,740 541 %
Interest and other income, net increased by $7.7 million in 2023 compared with 2022 mainly due to income from marketable securities corresponding to an increase in interest rates.
Income Taxes
The following table sets forth our income taxes (dollars in thousands):
Years Ended December 31,2023 vs 2022 Change
20232022$%
Income taxes$5,432 $13,032 $(7,600)(58)%
Effective tax rate16 %24 %
During 2023, our current tax expense was $6.1 million, and our deferred tax expense was $(0.7) million. Our effective tax rate was lower than the federal statutory rate of 21% primarily due to research and development tax credits and provision to return adjustments, partially offset by the impact of stock-based compensation and uncertain tax positions.
During 2022, our current tax expense was $11.1 million, and our deferred tax expense was $1.9 million. Our effective tax rate was higher than the federal statutory rate of 21% due to state taxes, the U.S. tax impact of foreign operations, and the impact of stock-based compensation, partially offset by research and development tax credits and stock option windfall deductions.
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We continue to maintain a valuation allowance of $29.9 million on certain U.S. federal and California state deferred tax assets that we believe are not more likely than not to be realized in future periods.
Our income taxes may be subject to fluctuation during the year and in future years as new information is obtained, which may affect the assumptions used to estimate the annual effective tax rate, including factors such as actual results differing from our estimates of pre-tax earnings in the various jurisdictions in which we operate, which could impact the recognition of our deferred tax assets, the recognition or de-recognition of tax benefits related to uncertain tax positions and changes in or the interpretation of tax laws in jurisdictions where we conduct business.
2022 Compared to 2021
For a comparison of our results of operations for the years ended December 31, 2022 and 2021, see Item 7 “Management’s Discussion and Analysis of Financial Condition and Results of Operations” of our Annual Report on Form 10-K for the year ended December 31, 2022 filed with the SEC on February 21, 2023.
Liquidity and Capital Resources
Historically, we have funded our operations and investing activities primarily through cash flow generated from operations, sales of our common stock and various borrowing arrangements. As of December 31, 2023, we had cash, cash equivalents and marketable securities of $220.3 million, which consisted of deposits held at banks and major financial institutions and highly liquid marketable securities such as U.S. government securities and commercial paper. This includes $7.7 million of cash primarily held by our foreign subsidiaries. As of December 31, 2023, our liability for taxes that would be payable because of repatriation of undistributed earnings of our foreign subsidiaries to the United States was not significant and limited to withholding taxes considering our existing net operating loss carryovers.
The following table presents the cash inflows and outflows by activity during 2023 and 2022 (in thousands):
Years Ended December 31,
20232022
Net cash provided by operating activities$56,251 $27,183 
Net cash used in investing activities(6,245)(24,082)
Net cash provided by financing activities(65,926)25,063 
Operating Activities
Our operating activities provided cash of $56.3 million in 2023 and $27.2 million in 2022. The increase in net cash provided by operating activities during 2023 as compared to 2022 was due primarily to an increase in our net operating results after adjustment of non-cash charges of $2.9 million and an increase in our net cash inflow resulting from changes in operating assets and liabilities of $26.1 million. Non-cash charges consisted of stock-based compensation of $62.8 million, depreciation and amortization of $16.6 million and deferred income taxes of $0.7 million partially offset by net accretion of available-for-sale securities of $4.2 million.
In 2023, cash outflows from changes in operating assets and liabilities primarily consisted of an increase in prepaid expenses and other assets of $60.8 million, mainly due to advanced payments to supply chain partners, an increase in prepaid taxes and reclassification of contract assets from deferred revenue; an increase in accounts receivable of $32.2 million due to the timing of shipments; and a decrease in accounts payable of $6.4 million due to the timing of inventory payments. These changes were partially offset by an increase in accrued liabilities of $32.7 million, mainly due to an increase in the reserves for inventory at suppliers, a decrease in inventory of $16.2 million and an increase in deferred revenue of $2.9 million.
Investing Activities
In 2023, net cash used in investing activities of $6.2 million consisted of capital expenditures of $17.9 million, primarily consisting of purchases of test and computer equipment and software, partially offset by net maturities of marketable securities of $11.6 million.
Financing Activities
In 2023, net cash used in financing activities of $65.9 million consisted of purchases of our common stock of $86.4 million and payments related to a financing arrangement of $11.7 million, partially offset by proceeds from the issuance of common stock related to our equity plans of $32.1 million.
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2022 Compared to 2021
For a discussion of our liquidity and capital resources and our cash flow activities for the years ended December 31, 2022 and 2021, see Item 7 “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” of our Annual Report on Form 10-K for the year ended December 31, 2022, filed with the SEC on February 21, 2023.
Working Capital and Capital Expenditure Needs
Our material cash commitments include non-cancelable firm purchase commitments, normal recurring trade payables, compensation-related and expense accruals and operating leases. We believe that our outsourced approach to manufacturing provides us significant flexibility in both managing inventory levels and financing our inventory. Furthermore, we maintain a common stock repurchase program of which $113.6 million was available as of December 31, 2023. Our stock repurchase program does not require us to purchase a specific number of shares and may be modified, suspended or terminated at any time.
We believe, based on our current operating plan and expected operating cash flows, that our existing cash, cash equivalents and marketable securities will be sufficient to meet our anticipated cash needs for at least the next twelve months. If we are unable to generate sufficient cash flows or obtain other sources of liquidity, we will be forced to terminate our stock repurchase program, limit our development activities, reduce our investment in growth initiatives and institute cost-cutting measures, all of which may adversely impact our business and potential growth.
Contractual Obligations and Commitments
Our principal commitments as of December 31, 2023 consisted of our contractual obligations under non-cancelable outstanding purchase obligations and operating lease obligations for office space. The following table summarizes our contractual obligations as of December 31, 2023 (in thousands):
Payments Due by Period
TotalLess Than 1 Year1-3 Years3-5 YearsMore Than 5 Years
Non-cancelable purchase commitments (1)
$219,989 $140,521 $69,145 $6,649 $3,674 
Operating lease obligations (2)
12,454 4,676 5,978 1,576 224 
$232,443 $145,197 $75,123 $8,225 $3,898 

(1) Represents outstanding purchase commitments to be delivered by our third-party manufacturers or other vendors. See Note 5 “Commitments and Contingencies” of the Notes to Consolidated Financial Statements included in this Annual Report on Form 10-K for further discussion regarding our outstanding purchase commitments related to our third-party manufacturers.
(2) Future minimum operating lease obligations in the table above primarily include payments for our office locations, which expire at various dates through 2029. See Note 5 “Commitments and Contingencies” of the Notes to Consolidated Financial Statements included in this Annual Report on Form 10-K for further discussion regarding our operating leases.
ITEM 7A.    Quantitative and Qualitative Disclosures About Market Risk
Interest Rate Risk
The primary objectives of our investment activity are to preserve principal, provide liquidity and maximize income without significantly increasing risk. By policy, we do not enter into investments for trading or speculative purposes. As of December 31, 2023, we had cash, cash equivalents and marketable securities of $220.3 million, which was held primarily in cash, money market funds and highly liquid marketable securities such as U.S. government securities and commercial paper. Due to the nature of these money market funds and highly liquid marketable securities, we believe that we do not have any material exposure to changes in the fair value of our cash equivalents and marketable securities because of changes in interest rates.
Foreign Currency Exchange Risk
Our primary foreign currency exposures are described below.
Economic Exposure
The direct effect of foreign currency fluctuations on our sales and expenses has not been material because our sales and expenses are primarily denominated in U.S. dollars, or USD. However, we are indirectly exposed to changes in foreign currency exchange rates to the extent of our use of foreign CMs whom we pay in USD. Increases in the local currency rates of these vendors in relation to USD could cause an increase in the price of products that we purchase. Additionally, if the USD
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strengthens relative to other currencies, such strengthening could have an indirect effect on our sales to the extent it raises the cost of our products to non-U.S. customers and thereby reduces demand. A weaker USD could have the opposite effect. The precise indirect effect of currency fluctuations is difficult to measure or predict because our sales are influenced by many factors in addition to the impact of such currency fluctuations.
Translation Exposure
Our sales contracts are primarily denominated in USD and, therefore, most of our revenue is not subject to foreign currency risk. We are directly exposed to changes in foreign exchange rates to the extent such changes affect our expenses related to our foreign assets and liabilities with our subsidiaries in China, India and the United Kingdom, whose functional currencies are Chinese Renminbi, or RMB, Indian Rupee, or INR, and British Pounds Sterling, or GBP.
Our operating expenses are incurred primarily in the United States, in China associated with our research and development operations that are maintained there, in India for our center of excellence and in the United Kingdom for our international sales and marketing activities. Our operating expenses are generally denominated in the functional currencies of our subsidiaries in which the operations are located. The percentages of our operating expenses denominated in the following currencies for the indicated fiscal years were as follows:
Years Ended December 31,
2023 2022 2021
USD90 %91 %92 %
RMB
INR— 
GBP
100 %100 %100 %
If USD had appreciated or depreciated by 10%, relative to RMB, GBP and INR, our operating expenses for 2023 would have decreased or increased by approximately $4.9 million, or approximately 1%.
Foreign exchange rate fluctuations may also adversely impact our financial position as the assets and liabilities of our foreign operations are translated into USD in preparing our Consolidated Balance Sheets. The effect of foreign exchange rate fluctuations on our consolidated financial position for the year ended December 31, 2023 was a net translation gain of $0.1 million. This gain is recognized as an adjustment to stockholders’ equity through “Accumulated other comprehensive loss.”
Transaction Exposure
We have certain assets and liabilities, primarily accounts receivable and accounts payable (including inter-company transactions) that are denominated in currencies other than the relevant entity’s functional currency. In certain circumstances, changes in the functional currency value of these assets and liabilities create fluctuations in our reported consolidated financial position, cash flows and results of operations. Periodically, we use derivatives to hedge against fluctuations in foreign exchange rates. We do not enter into derivatives for speculative or trading purposes. We use foreign currency forward contracts to mitigate variability in gains and losses generated from the re-measurement of certain assets denominated in foreign currencies. These foreign exchange forward contracts typically have maturities of approximately one to two months. As of December 31, 2023, we had no forward contracts outstanding. Transaction gains and losses on these foreign currency denominated assets and liabilities are recognized each period within “Other expense, net” in our Consolidated Statements of Comprehensive Income. During the year ended December 31, 2023, the net loss we recognized related to these foreign exchange assets and liabilities was approximately $0.2 million.
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ITEM 8.     Financial Statements and Supplementary Data

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Report of Independent Registered Public Accounting Firm
To the Stockholders and Board of Directors
Calix, Inc.:

Opinions on the Consolidated Financial Statements and Internal Control Over Financial Reporting
We have audited the accompanying consolidated balance sheets of Calix, Inc. and subsidiaries (the Company) as of December 31, 2023 and 2022, the related consolidated statements of comprehensive income, stockholders’ equity, and cash flows for each of the years in the three-year period ended December 31, 2023, and the related notes (collectively, the consolidated financial statements). We also have audited the Company’s internal control over financial reporting as of December 31, 2023, based on criteria established in Internal Control Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission.
In our opinion, the consolidated financial statements referred to above present fairly, in all material respects, the financial position of the Company as of December 31, 2023 and 2022, and the results of its operations and its cash flows for each of the years in the three-year period ended December 31, 2023, in conformity with U.S. generally accepted accounting principles. Also in our opinion, the Company maintained, in all material respects, effective internal control over financial reporting as of December 31, 2023 based on criteria established in Internal Control Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission.
Basis for Opinions
The Company’s management is responsible for these consolidated financial statements, for maintaining effective internal control over financial reporting, and for its assessment of the effectiveness of internal control over financial reporting, included in the accompanying Management’s Report on Internal Control Over Financial Reporting. Our responsibility is to express an opinion on the Company’s consolidated financial statements and an opinion on the Company’s internal control over financial reporting based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.
We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audits to obtain reasonable assurance about whether the consolidated financial statements are free of material misstatement, whether due to error or fraud, and whether effective internal control over financial reporting was maintained in all material respects.
Our audits of the consolidated financial statements included performing procedures to assess the risks of material misstatement of the consolidated financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the consolidated financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the consolidated financial statements. Our audit of internal control over financial reporting included obtaining an understanding of internal control over financial reporting, assessing the risk that a material weakness exists, and testing and evaluating the design and operating effectiveness of internal control based on the assessed risk. Our audits also included performing such other procedures as we considered necessary in the circumstances. We believe that our audits provide a reasonable basis for our opinions.
Definition and Limitations of Internal Control Over Financial Reporting
A company’s internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. A company’s internal control over financial reporting includes those policies and procedures that (1) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the company; (2) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and (3) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the company’s assets that could have a material effect on the financial statements.
Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.
Critical Audit Matter
The critical audit matter communicated below is a matter arising from the current period audit of the consolidated financial statements that was communicated or required to be communicated to the audit committee and that: (1) relates to accounts or disclosures that are material to the consolidated financial statements and (2) involved our especially challenging, subjective, or complex judgments. The communication of a critical audit matter does not alter in any way our opinion on the consolidated financial statements, taken as a whole, and we are not, by communicating the critical audit matter below, providing a separate opinion on the critical audit matter or on the accounts or disclosures to which it relates.
36

Evaluation of net realizable value of raw material and finished goods inventory and excess and obsolete component liabilities
As discussed in Notes 1, 4 and 5 to the consolidated financial statements, the Company has raw material and finished goods inventories with a carrying value of $133.0 million and excess and obsolete component liabilities of $32.2 million as of December 31, 2023. The Company adjusts the inventory carrying value for excess or obsolete inventory based on assumptions about future demand for products, potential obsolescence of technology, product life cycle, and whether pricing trends or forecasts indicate that the carrying value of inventory exceeds the estimated selling price. These factors are impacted by market and economic conditions, technology changes and new product introductions and require significant estimates that may include elements that are uncertain. The Company also records a liability and a charge to cost of revenue for estimated losses on components the Company is obligated to purchase from its manufacturers when the components have been rendered excess and obsolete due to manufacturing and engineering change orders resulting from design changes, manufacturing discontinuation of products by its suppliers, or in cases where the Company has committed component levels that greatly exceed projected demand. During the fourth quarter of 2023, the Company took charges of $28.7 million to write down excess and obsolete inventory and accrue a liability for components at suppliers primarily associated with the Company’s legacy product family.
We identified the evaluation of net realizable value of inventory and excess and obsolete component liabilities as a critical audit matter. Evaluation of the Company’s forecasted demand, including the Company’s determination of the effect of market and economic conditions, technology and design changes, new product introductions, and discontinuation of products both by the Company and its suppliers required significant auditor judgment.
The following are the primary procedures we performed to address this critical audit matter. We evaluated the design and tested the operating effectiveness of certain internal controls related to the Company’s inventory process. This included controls over the reviews of the estimates of the net realizable value of excess or obsolete raw material and finished goods inventory and liabilities for losses on components the Company is obligated to purchase from its manufacturers. For a selection of inventory items owned by the Company, we (1) reperformed the analysis provided by the Company to assess the accuracy of the net realizable value of inventory by comparing historical sales activity, customer order backlog, or demand forecasts to the inventory on hand quantities, and (2) performed inquiries of Company’s personnel and inspected documents regarding product end of life announcements, technology and design changes, and new product introductions. For a selection of components subject to the Company’s purchase commitments, we (1) evaluated the reasonableness of management’s assumptions used to estimate the excess and obsolete component liabilities by considering historical sales activity, customer order backlog, or demand forecasts of the related finished products and (2) performed inquiries of Company’s personnel and inspected documents regarding product end of life announcements, technology and design changes, new product introductions, and historical reimbursements to suppliers for excess and obsolete components.

/s/ KPMG LLP
We have served as the Company’s auditor since 2016.
Santa Clara, California
February 22, 2024
37

CALIX, INC.
CONSOLIDATED BALANCE SHEETS
(In thousands, except par value)
 
December 31,
20232022
ASSETS
Current assets:
Cash and cash equivalents$63,409 $79,073 
Marketable securities156,937 162,642 
Accounts receivable, net126,027 93,804 
Inventory132,985 149,160 
Prepaid expenses and other current assets118,598 62,691 
Total current assets597,956 547,370 
Property and equipment, net29,461 25,834 
Right-of-use operating leases9,262 9,283 
Deferred tax assets167,691 167,031 
Goodwill116,175 116,175 
Other assets21,320 19,142 
$941,865 $884,835 
LIABILITIES AND STOCKHOLDERS’ EQUITY
Current liabilities:
Accounts payable$34,746 $41,407 
Accrued liabilities116,227 90,474 
Deferred revenue36,669 33,541 
Total current liabilities187,642 165,422 
Long-term portion of deferred revenue24,864 25,072 
Operating leases7,421 8,442 
Other long-term liabilities2,956 6,332 
Total liabilities222,883 205,268 
Commitments and contingencies (See Note 5)
Stockholders’ equity:
Preferred stock, $0.025 par value; 5,000 shares authorized; no shares issued and outstanding as of December 31, 2023 and 2022
  
Common stock, $0.025 par value; 100,000 shares authorized; 65,052 shares issued and outstanding as of December 31, 2023, and 65,735 shares issued and outstanding as of December 31, 2022
1,627 1,644 
Additional paid-in capital1,078,393 1,070,100 
Accumulated other comprehensive loss(659)(2,473)
Accumulated deficit(360,379)(389,704)
Total stockholders’ equity718,982 679,567 
$941,865 $884,835 

See accompanying notes to consolidated financial statements.

38

CALIX, INC.
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
(In thousands, except per share data)
 
 Years Ended December 31,
202320222021
Revenue$1,039,593 $867,827 $679,394 
Cost of revenue521,277 432,399 322,807 
Gross profit518,316 435,428 356,587 
Operating expenses:
Sales and marketing214,564 174,549 125,909 
Research and development177,772 131,994 101,747 
General and administrative100,395 76,275 55,779 
Restructuring benefit  (786)
Total operating expenses492,731 382,818 282,649 
Operating income25,585 52,610 73,938 
Interest and other income (expense), net:
Interest income (expense), net9,704 2,009 (402)
Other expense, net(532)(577)(882)
Total interest and other income (expense), net9,172 1,432 (1,284)
Income before income taxes34,757 54,042 72,654 
Income taxes5,432 13,032 (165,724)
Net income$29,325 $41,010 $238,378 
Net income per common share:
Basic$0.44 $0.63 $3.77 
Diluted$0.42 $0.60 $3.51 
Weighted-average number of shares used to compute net income per common share:
Basic65,980 65,058 63,277 
Diluted69,320 68,911 67,856 
Net income$29,325 $41,010 $238,378 
Other comprehensive income (loss), net of tax:
Unrealized gain (loss) on available-for-sale marketable securities, net1,701 (1,521)(179)
Foreign currency translation adjustments, net113 (632)50 
Total other comprehensive income (loss), net of tax1,814 (2,153)(129)
Comprehensive income$31,139 $38,857 $238,249 

See accompanying notes to consolidated financial statements.
39

CALIX, INC.
CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY
(In thousands)
Accumulated
AdditionalOtherTotal
Common StockPaid-inComprehensiveAccumulatedStockholders’
SharesAmountCapitalLossDeficitEquity
Balance as of December 31, 202062,122 $1,553 $948,055 $(191)$(669,092)$280,325 
Stock-based compensation— — 24,230 — — 24,230 
Issuance of common stock under equity incentive plans, net of forfeitures2,152 54 25,570 — — 25,624 
Net income— — — — 238,378 238,378 
Other comprehensive loss— — — (129)— (129)
Balance as of December 31, 202164,274 1,607 997,855 (320)(430,714)568,428 
Stock-based compensation— — 44,826 — — 44,826 
Issuance of common stock under equity incentive plans, net of forfeitures1,461 37 27,419 — — 27,456 
Net income— — — — 41,010 41,010 
Other comprehensive loss— — — (2,153)— (2,153)
Balance as of December 31, 202265,735 1,644 1,070,100 (2,473)(389,704)679,567 
Stock-based compensation— — 62,771 — — 62,771 
Issuance of common stock under equity incentive plans, net of forfeitures1,527 38 32,111 — — 32,149 
Repurchase of common stock including excise tax(2,210)(55)(86,589)— — (86,644)
Net income— — — — 29,325 29,325 
Other comprehensive income— — — 1,814 — 1,814 
Balance as of December 31, 202365,052 1,627 1,078,393 (659)(360,379)718,982 

See accompanying notes to consolidated financial statements.

40

CALIX, INC.
CONSOLIDATED STATEMENTS OF CASH FLOWS
(In thousands)
 Years Ended December 31,
202320222021
Operating activities:
Net income$29,325 $41,010 $238,378 
Adjustments to reconcile net income to net cash provided by operating activities:
Stock-based compensation62,771 44,826 24,230 
Depreciation and amortization16,631 14,315 15,012 
Deferred income taxes(660)1,932 (168,426)
Net accretion of available-for-sale securities(4,199)(1,146) 
Changes in operating assets and liabilities:
Accounts receivable, net(32,222)(8,585)(15,800)
Inventory16,175 (60,280)(36,612)
Prepaid expenses and other assets(60,795)(38,359)(27,074)
Accounts payable(6,369)12,111 16,025 
Accrued liabilities37,070 20,919 3,273 
Deferred revenue2,921 9,118 10,400 
Other long-term liabilities(4,397)(8,678)(2,613)
Net cash provided by operating activities56,251 27,183 56,793 
Investing activities:
Purchases of property and equipment(17,855)(14,067)(10,463)
Purchases of marketable securities(216,193)(191,403)(298,092)
Maturities of marketable securities227,803 181,388 197,894 
Net cash used in investing activities(6,245)(24,082)(110,661)
Financing activities:
Proceeds from common stock issuances related to employee benefit plans32,149 27,456 25,624 
Repurchases of common stock(86,397)  
Payments related to financing arrangements(11,678)(2,393)(1,241)
Net cash provided by (used in) financing activities(65,926)25,063 24,383 
Effect of exchange rate changes on cash and cash equivalents256 (424)11 
Net increase (decrease) in cash and cash equivalents(15,664)27,740 (29,474)
Cash and cash equivalents at beginning of year79,073 51,333 80,807 
Cash and cash equivalents at end of year$63,409 $79,073 $51,333 
Supplemental disclosures of cash flow information:
Interest paid$253 $577 $631 
Income taxes paid$11,873 9,607 5,197 
Non-cash investing activities:
Changes in accounts payable and accrued liabilities related to purchases of property and equipment$(180)$586 $194 

See accompanying notes to consolidated financial statements.
41

CALIX, INC.
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
1. Description of Business and Significant Accounting Policies
Company
Calix, Inc. (together with its subsidiaries, “Calix” or the “Company”) was incorporated in August 1999 and is a Delaware corporation. The Company is the leading global provider of a platform (cloud, software and systems) and managed services that focus on the subscriber-facing network, the portion of the network that governs available bandwidth and determines the range and quality of services that can be offered to subscribers. This platform and managed services enable broadband service providers (“BSPs”) of all sizes to innovate and transform their businesses. The Company’s BSP customers are empowered to utilize real-time data and insights from the Calix platform to simplify their businesses and deliver experiences that excite their subscribers. These insights enable BSPs to grow their businesses through increased subscriber acquisition, loyalty and revenue, thereby increasing the value of their businesses and contributions to their communities.
Basis of Presentation and Accounting Guidance
The accompanying consolidated financial statements have been prepared in accordance with the requirements of the U.S. Securities and Exchange Commission (“SEC”) and U.S. generally accepted accounting principles (“GAAP”). All significant intercompany balances and transactions have been eliminated in consolidation. Any reference in these notes to applicable accounting guidance is meant to refer to the authoritative U.S. GAAP as found in the Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”).
Use of Estimates
The preparation of financial statements is in conformity with U.S. GAAP, which requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. For the Company, these estimates include, but are not limited to: allowances for doubtful accounts and sales returns, excess and obsolete inventory, allowances for obligations to its contract manufacturers, valuation of stock-based compensation, useful lives assigned to long-lived assets, standard and extended warranty costs, realizability of deferred tax assets and uncertain tax positions and contingencies. Actual results could differ from those estimates, and such differences could be material to the Company’s financial position and results of operations.
Revenue Recognition
Revenue is recognized when a performance obligation is satisfied, which occurs when control of the promised goods or services is transferred to the customer, in an amount that reflects the consideration the Company expects to be entitled to in exchange for those goods or services. Revenue from sales of access and premises systems is recognized when control is transferred to the customer, which is generally when the products are shipped. Revenue from software platform licenses, which provides the customer with a right to use the software as it exists, is generally recognized upfront when made available to the customer. Revenue from cloud-based software subscriptions, customer support, maintenance, extended warranty subscriptions and managed services is generally recognized ratably over the contract term. Revenue from professional services and training is recognized as the services are delivered.
A performance obligation is a promise in a contract to transfer a distinct good or service to the customer and is the unit of account. A contract’s transaction price is allocated to each distinct performance obligation and recognized as revenue when, or as, the performance obligation is satisfied. The Company’s hardware products contain both software and non-software components that function together to deliver the products’ essential functionality and therefore constitutes a single performance obligation as the promise to transfer the individual software and non-software components is not separately identifiable and, therefore, not distinct. Cloud-based software subscriptions can include multi-year agreements with a fixed annual fee for a minimum committed usage level. To the extent that minimum committed usage level each year varies, the Company has concluded that each year represents a distinct stand-ready performance obligation and the transaction price allocated to each performance obligation is recognized as revenue ratably over each annual period. The Company’s contracts may include multiple performance obligations. For such arrangements, the Company allocates the contract’s transaction price to each performance obligation using the relative stand-alone selling price of each distinct good or service in the contract. The Company generally determines stand-alone selling prices based on the prices charged to customers or its best estimate of stand-alone selling price. The Company’s estimate of stand-alone selling price is established considering multiple factors including, but not limited to, geographies, market conditions, competitive landscape, internal costs, gross margin objectives, characteristics of targeted customers and pricing practices. The determination of estimated stand-alone selling price is made through consultation with and formal approval by management, taking into consideration the go-to-market strategy.
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Cost of Revenue
Cost of revenue consists primarily of finished goods inventory purchased from the Company’s contract manufacturers, payroll and related expenses associated with managing the relationships with contract manufacturers, depreciation of manufacturing test equipment, warranty and retrofit costs, excess and obsolete inventory costs, allowances for obligations to its contract manufacturers, shipping charges and amortization of certain intangible assets. It also includes contractor and other costs of services incurred directly related to the delivery of services to customers.
Warranty and Retrofit
The Company offers limited warranties for its hardware products for a period of one, three or five years, depending on the product type. The Company recognizes estimated costs related to warranty activities as a component of cost of revenue upon product shipment or upon identification of a specific product failure. Under certain circumstances, the Company also provides fixes on specifically identified performance failures for products that are outside of the standard warranty period and recognizes estimated costs related to retrofit activities as a component of cost of revenue upon identification of such product failures. The Company recognizes estimated warranty and retrofit costs when it is probable that a liability has been incurred and the amount of loss is reasonably estimable. The estimates are based upon historical and projected product failure and claim rates, historical costs incurred in correcting product failures and information available related to any specifically identified product failures. Judgment is required in estimating costs associated with warranty and retrofit activities, and the Company's estimates are limited to information available to the Company at the time of such estimates. In some cases, such as when a specific product failure is first identified or a new product is introduced, the Company may initially have limited information and limited historical failure and claim rates upon which to base its estimates, and such estimates may require revision in future periods. The recorded amount is adjusted from time to time for specifically identified warranty and retrofit exposure. Actual warranty and retrofit expenses are charged against the Company’s estimated warranty and retrofit liability when incurred. Factors that affect the Company’s warranty and retrofit liability include the number of active installed units and historical and anticipated rates of warranty and retrofit claims and cost per claim.
Stock-Based Compensation
Stock-based compensation expense associated with stock options and purchase rights under the Amended and Restated Employee Stock Purchase Plan (the “ESPP”) and the Amended and Restated 2017 Nonqualified Employee Stock Purchase Plan (the “NQ ESPP”) is measured at the grant date based on the fair value of the award and is recognized, net of forfeitures, as expense over the remaining requisite service period (generally the vesting period) on a straight-line basis.
The fair value of stock option and employee stock purchase right under the ESPP is estimated at the grant date using the Black-Scholes option valuation model. The fair value of the employee stock purchase right under the NQ ESPP is based on closing market price of the Company’s common stock on the date of grant.
Stock-based compensation expense associated with performance stock options (“PSOs”) with graded vesting features and which contain both a performance and a service condition is measured based on fair value of stock options estimated at the grant date using the Black-Scholes option valuation model, and is recognized, net of forfeitures, as expense over the requisite service period using the graded vesting attribution method.
Compensation expense is only recognized if the Company has determined that it is probable that the performance condition will be met. The Company reassesses the probability of vesting at each reporting period and adjusts compensation expense based on its probability assessment.
Loss Contingencies
From time to time, the Company is involved in legal proceedings arising from the normal course of business activities. The Company evaluates the likelihood of an unfavorable outcome of legal proceedings to which it is a party and accrues a loss contingency when the loss is probable and reasonably estimable. Assessing legal contingencies involves significant judgment and estimates, and the outcome of litigation is inherently uncertain and subject to numerous factors outside the Company’s control. Significant judgment is required when the Company assesses the likelihood of any adverse judgments or outcomes, including the potential range of possible losses, and whether losses are probable and reasonably estimable.
Because of uncertainties related to these matters, the Company bases its estimates of whether a loss contingency is probable or reasonably possible, as well as the reasonable range of possible losses associated with each loss contingency, only on the information available at the time. As additional information becomes available, and at least quarterly, the Company reassesses the potential liability on each significant matter and may revise its estimates. These revisions could have a material impact on the Company’s business, operating results or financial condition. The actual outcome of these legal proceedings may materially differ from the Company’s estimates of potential liability, which could have a material adverse effect on the Company’s business, operating results or financial condition.
43

Credit Risk and Inventory Supplier Concentrations
Financial instruments that potentially subject the Company to significant concentrations of credit risk consist primarily of cash, cash equivalents, marketable securities and accounts receivable. Cash equivalents consist of money market funds and marketable securities with a maturity at the date of purchase of ninety days or less, which are invested through financial institutions in the United States. Deposits in and investments held by these financial institutions may, at times, exceed federally insured limits. The Company has not experienced any losses in such accounts. The Company also has approximately $7.7 million of cash held by its foreign subsidiaries in India, China and the United Kingdom. Management believes that the financial institutions that hold the Company’s cash and cash equivalents are financially sound and, accordingly, minimal credit risk exists with respect to these cash and cash equivalents.
The Company depends primarily on a small number of outside contract manufacturers (“CMs”) and original design manufacturers (“ODMs”) for the bulk of its finished goods inventory. The Company generally purchases its products through purchase orders with its suppliers. While the Company seeks to maintain a sufficient supply of its products, the Company’s business and results of operations could be adversely affected by a stoppage or delay in receiving such products, the receipt of defective parts, an increase in price of such products or the Company’s inability to obtain lower prices from its CMs, ODMs and other suppliers in response to competitive pressures.
Fair Value of Financial Instruments
The carrying amounts of cash and cash equivalents, trade receivables, accounts payable and other accrued liabilities approximate their fair value due to their relatively short-term nature. Marketable securities are valued using quoted market prices in active markets to determine fair value.
Cash, Cash Equivalents and Marketable Securities
Cash equivalents and marketable securities are stated at amounts that approximate fair value based on quoted market prices.
The Company has invested its excess cash primarily in money market funds and highly liquid marketable securities such as U.S. treasury securities, corporate debt instruments, commercial paper and U.S. government securities. The Company considers all investments with maturities of three months or less when purchased to be cash equivalents. Marketable securities represent highly liquid U.S. treasury securities, corporate debt instruments, commercial paper and U.S. government securities with maturities greater than 90 days at date of purchase. Marketable securities with maturities greater than one year are classified as current because management considers all marketable securities to be available for current operations.
The Company’s investments have been classified and accounted for as available-for-sale. Such investments are recorded at fair value and unrealized holding gains and losses are reported as a separate component of comprehensive loss in the stockholders’ equity until realized. Realized gains and losses on sales of marketable securities, if any, are determined on the specific identification method and are reclassified from accumulated other comprehensive loss to results of operations as “Other expense, net.” Realized gains and losses were not significant for the years ended December 31, 2023 and 2022, respectively.
For the Company’s available-for-sale debt securities in an unrealized loss position, the Company determines whether a credit loss exists. In this assessment, among other factors, the Company considers the extent to which the fair value is less than the amortized cost, any changes to the rating of the security by a rating agency, and adverse conditions specifically related to the security. If factors indicate a credit loss exists, an allowance for credit loss will be recorded to “Other expense, net,” limited by the amount that the fair value is less than the amortized cost basis. The amount of fair value change relating to all other factors will be recognized in other comprehensive loss.
See Note 2 “Cash, Cash Equivalents and Marketable Securities.”
Allowance for Doubtful Accounts
The Company maintains an allowance for doubtful accounts for expected credit losses at contract inception resulting from the inability of its customers to make required payments. The Company records a specific allowance and revises the expected loss based on an analysis of individual past-due balances. Additionally, based on historical write-offs and the Company’s collection experience, the Company records an additional allowance based on a percentage of outstanding receivables. The Company performs credit evaluations of its customers’ financial condition. These evaluations require judgment and are based on a variety of factors including, but not limited to, current economic trends, payment history and a financial review of the customer. Actual collection losses may differ from management’s estimates, and such differences could be material to the Company’s financial position and results of operations.
Inventory Valuation and Supplier Purchase Commitments
Inventory, which primarily consists of finished goods purchased from CMs or ODMs, is stated at the lower of cost (determined by the first-in, first-out method) or market value. Shipments from suppliers before the Company receives them are recorded as
44

in-transit inventory when title and the significant risks and rewards of ownership have passed to the Company. Inbound shipping costs and U.S. tariffs are included in cost of inventory. In addition, from time to time, the Company procures component inventory primarily as a result of manufacturing discontinuation of critical components by suppliers. The Company regularly monitors inventory quantities on hand and records write-downs for excess and obsolete inventories based on the Company’s estimate of demand for its products, potential obsolescence of technology, product life cycles and whether pricing trends or forecasts indicate that the carrying value of inventory exceeds its estimated selling price. The Company also evaluates its supplier purchase commitments, which remain elevated due to the extended lead-times during the global pandemic-induced supply chain challenges, and records a liability for excess and obsolete components based on its estimated demand of our products, potential obsolescence of technology and product life cycles. These factors are impacted by market and economic conditions, competitive dynamics, technology changes and new product introductions and require significant estimates that may include elements that are uncertain. Actual demand may differ from forecasted demand and may have a material effect on gross profit. If inventory is written down, a new cost basis is established that cannot be increased in future periods. For example, during the fourth quarter of 2023, the Company took charges of $28.7 million to write down excess and obsolete inventory and accrue a liability for components at suppliers primarily associated with the Company’s legacy product family that existed before its shift to an all-platform model. During 2023, customers moved to the Company’s platform model at a faster rate than originally anticipated, leaving the Company with excess finished goods and related components at suppliers.
Contract Costs
The Company capitalizes certain sales commissions related primarily to multi-year cloud-based software subscriptions and extended warranty support contracts.
Capitalized commissions are amortized as sales and marketing expenses over the period that the related revenue is recognized, which can be up to five years for extended warranty. The Company classifies the unamortized portion of deferred commissions as current or noncurrent based on the timing of when the Company expects to recognize the expense. The current and noncurrent portions of deferred commissions are included in “Prepaid expenses and other current assets” and “Other assets,” respectively, in the Company’s Consolidated Balance Sheets.
Property and Equipment
Property and equipment are stated at cost, less accumulated depreciation, and are depreciated using the straight-line method over the estimated useful life of each asset. Generally, computer equipment is depreciated over two years; purchased software is depreciated over three to five years; test equipment is depreciated over three years; furniture and fixtures are depreciated over seven years; and leasehold improvements are depreciated over the shorter of the respective lease term or the estimated useful life of the asset. Maintenance and repairs are charged to expense as incurred.
Goodwill
Goodwill was recorded as a result of the Company’s acquisitions of Occam Networks, Inc. in February 2011 and Optical Solutions, Inc. in February 2006. The Company records goodwill when consideration paid in a business acquisition exceeds the fair value of the net tangible assets and the identified intangible assets acquired. Goodwill is not amortized but instead is subject to an annual impairment test or more frequently if events or changes in circumstances indicate that it may be impaired. The Company evaluates goodwill on an annual basis as of the end of the second quarter of each fiscal year. Management has determined that it operates as a single reporting unit and, therefore, evaluates goodwill impairment at the enterprise level.
At the end of the second quarter of 2023, the Company completed its annual goodwill impairment test. Based on its assessment of certain qualitative factors such as market capitalization, management concluded that the fair value of the Company was more likely than not greater than its carrying amount as of July 2, 2023. As such, it was not necessary to perform the two-step quantitative goodwill impairment test at the time.
There have been no significant events or changes in circumstances subsequent to the 2023 annual impairment test that would more likely than not indicate that the carrying value of goodwill may have been impaired as of December 31, 2023. There were no impairment losses for goodwill for the years ended December 31, 2023, 2022 or 2021.
Deferred Revenue
Deferred revenue results from transactions where the Company billed the customer for products or services and when cash payments are received or due prior to transferring control of the promised goods or services to the customer.
Payment terms to customers typically range from net 30 to net 90 days and vary by the size and location of customer and the products or services offered. The period between the transfer of control of the promised good or service to a customer and when payment is due is not significant.
45

Income Taxes
The Company evaluates its tax positions and estimates its current tax exposure along with assessing temporary differences that result from different book to tax treatment of items not currently deductible for tax purposes. These differences result in deferred tax assets and liabilities on the Company’s Consolidated Balance Sheets, which are estimated based upon the difference between the financial statement and tax bases of assets and liabilities using the enacted tax rates that will be in effect when these differences reverse. In general, deferred tax assets represent future tax benefits to be received when certain expenses previously recognized in the Company’s Consolidated Statements of Comprehensive Income become deductible expenses under applicable income tax laws or loss or credit carryforwards are utilized. Accordingly, realization of the Company’s deferred tax assets is dependent on future taxable income against which these deductions, losses and credits can be utilized.
The Company must assess the likelihood that deferred tax assets will be recovered from future taxable Income, and if the Company determines that recovery is not more likely than not, the Company must establish a valuation allowance. Management judgment is required in determining its provision for income taxes, deferred tax assets and liabilities and any valuation allowance recorded against its net deferred tax assets.
Newly Adopted Accounting Standards
The Company did not adopt any new accounting standards in 2023 that were significant to the Company.
Recent Accounting Pronouncements Not Yet Adopted
There have been no accounting pronouncements or changes in accounting pronouncements that are significant or potentially significant to the Company.
2. Cash, Cash Equivalents and Marketable Securities
Cash, cash equivalents and marketable securities consisted of the following (in thousands):

December 31,
20232022
Cash and cash equivalents:
Cash$18,040 $39,189 
Commercial paper32,837 33,199 
U.S. government securities9,969 5,990 
Money market funds2,563 555 
Corporate debt securities 140 
Total cash and cash equivalents63,409 79,073 
Marketable securities:
U.S. government securities92,277 106,750 
U.S. government agency securities43,521 23,632 
Commercial paper14,139 28,992 
Corporate debt securities7,000 3,168 
Municipal securities 100 
Total marketable securities156,937 162,642 
$220,346 $241,715 
The carrying amounts of the Company’s money market funds approximate their fair values due to their nature, duration and short maturities. As of December 31, 2023, all marketable securities were due in three years or less.
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The amortized cost and fair value of marketable securities as of December 31, 2023 were as follows (in thousands):
Amortized CostGross Unrealized Gains (Losses)Fair Value
U.S. government securities$102,167 $80 $102,247 
Commercial paper47,003 (28)46,975 
U.S. government agency securities43,573 (52)43,521 
Corporate debt securities6,999 1 7,000 
$199,742 $1 $199,743 
The amortized cost and fair value of marketable securities as of December 31, 2022 were as follows (in thousands):
Amortized CostGross Unrealized LossesFair Value
U.S. government securities$114,120 $(1,380)$112,740 
Commercial paper62,262 (71)62,191 
U.S. government agency securities23,876 (244)23,632 
Corporate debt securities3,312 (4)3,308 
Municipal securities101 (1)100 
$203,671 $(1,700)$201,971 

3. Fair Value Measurements
The Company measures its cash equivalents and marketable securities at fair value on a recurring basis. Fair value is an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability. The Company utilizes the following three-tier value hierarchy which prioritizes the inputs used in measuring fair value:
Level 1 – Observable inputs that reflect quoted prices (unadjusted) for identical assets or liabilities in active markets.
Level 2 – Observable inputs other than quoted prices included in Level 1 for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active, and model-driven valuations in which all significant inputs and significant value drivers are observable in active markets.
Level 3 – Unobservable inputs to the valuation derived from fair valuation techniques in which one or more significant inputs or significant value drivers are unobservable. The fair value hierarchy also requires the Company to maximize the use of observable inputs, when available, and to minimize the use of unobservable inputs when determining inputs and determining fair value.
The following tables sets forth the Company’s financial assets measured at fair value on a recurring basis based on the three-tier fair value hierarchy (in thousands):
As of December 31, 2023Level 1Level 2Total
Money market funds$2,563 $ $2,563 
U.S. government securities102,246  102,246 
Commercial paper 46,976 46,976 
U.S. government agency securities 43,521 43,521 
Corporate debt securities 7,000 7,000 
$104,809 $97,497 $202,306 

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As of December 31, 2022Level 1Level 2Total
Money market funds$555 $ $555 
U.S. government securities112,740  112,740 
Commercial paper 62,191 62,191 
U.S. government agency securities 23,632 23,632 
Corporate debt securities 3,308 3,308 
Municipal securities 100 100 
$113,295 $89,231 $202,526 
4. Balance Sheet Details
Accounts receivable, net consisted of the following (in thousands):
December 31,
20232022
Accounts receivable$126,331 $94,201 
Allowance for doubtful accounts(304)(397)
$126,027 $93,804 
The table below summarizes the changes in allowance for doubtful accounts and product return liability for the periods indicated (in thousands):
Balance at Beginning of YearAdditions Charged to Expenses or Revenue Net of RecoveriesWrite Offs and ReturnsBalance at
End of Year
Year Ended December 31, 2023:
Allowance for doubtful accounts$397 $43 $(136)$304 
Product return liability2,961 4,761 (4,825)2,897 
Year Ended December 31, 2022:
Allowance for doubtful accounts$725 $(276)$(52)$397 
Product return liability1,836 5,622 (4,497)2,961 
Year Ended December 31, 2021:
Allowance for doubtful accounts$1,405 $(201)$(479)$725 
Product return liability1,888 3,681 (3,733)1,836 
Inventory consisted of the following (in thousands):
December 31,
20232022
Raw materials$22,119 $640 
Finished goods110,866 148,520 
$132,985 $149,160 
Prepaid expenses and other current assets consisted of the following (in thousands):
December 31,
20232022
Supplier deposits$78,131 $39,064 
Prepaid expenses and other current assets40,467 23,627 
$118,598 $62,691 
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Property and equipment, net consisted of the following (in thousands):
December 31,
20232022
Test equipment$50,853 $44,106 
Computer equipment13,615 13,396 
Software12,972 10,389 
Leasehold improvements2,122 1,730 
Furniture and fixtures