RBBN US Equity☆

Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations

Overview

We are a leading global provider of communications technology to service providers and enterprises. We provide a broad range of software and high-performance hardware products, solutions and services that enable the secure delivery of data and voice communications for residential consumers and for small, medium and large enterprises and industry verticals such as finance, education, government, utilities and transportation. Our mission is to create a recognized global technology leader providing cloud-centric solutions that enable the secure exchange of information, with unparalleled scale, performance and elasticity. Headquartered in Plano, Texas, we have a global presence with research and development and/or sales and support locations in over thirty-five countries around the world.

Impact of COVID-19 on Our Business

In 2020, a novel strain of the coronavirus (COVID-19) was declared by the World Health Organization to be a global pandemic. The COVID-19 pandemic has had a negative effect on the global economy, disrupting the various manufacturing, commodity and financial markets and increasing volatility, and has impeded global supply chains, including that of our IP Optical Networks operating segment. Continued dampened global economic conditions as a result of the COVID-19 pandemic, particularly in areas experiencing slower vaccine rollout, such as Australia and India, may cause our customers to restrict spending or delay purchases for an indeterminate period of time and consequently cause our revenues to decline. In addition, our ability to deliver our solutions as agreed upon with our customers depends on the ability of our global contract manufacturers, vendors, licensors and other business partners to deliver products or perform services we have procured from them. While, to date, we have not experienced material issues, if the ongoing COVID-19 pandemic impairs the ability of our business partners to support us on a timely basis, or negatively impacts the demand for our customers' other products and services, our ability to perform our customer contracts as well as the demand for our solutions may suffer. In addition, disruptions from the COVID-19 pandemic could include, and with respect to our IP Optical Networks operating segment have included, disruption of logistics necessary to import, export and deliver our solutions. The COVID-19 pandemic continues to limit in some locations, including India, the ability of our employees to perform their work due to illness caused by the pandemic or local, state or federal orders requiring employees to remain at home. The degree to which the COVID-19 pandemic ultimately impacts our business, financial position and results of operations will depend on future developments beyond our control, including the effectiveness and timing of any vaccines, the frequency and duration of future waves of infection, the effectiveness and timing of any vaccines, the extent of actions to contain or treat the virus, how quickly and to what extent normal economic and operating conditions can resume, and the severity and duration of the global economic downturn that results from the pandemic.

As a response to the ongoing COVID-19 pandemic, we have continued to implement plans to manage our costs. We have significantly reduced travel and marketing expenses except where necessary to meet customer or regulatory needs and acted to limit discretionary spending. To the extent the business disruption continues for an extended period, additional cost management actions will be considered. Any future asset impairment charges, increases in the allowance for doubtful accounts or restructuring charges could be more likely and will be dependent on the severity and duration of this crisis.

Presentation

Unless otherwise noted, all financial amounts, excluding tabular information, in this MD&A are rounded to the nearest million dollar amount, and all percentages, excluding tabular information, are rounded to the nearest percentage point.

Reclassifications

In 2021, we reclassified amounts recorded for amortization of certain acquired intangible assets in prior presentations from Total operating expenses under the caption "Amortization of acquired intangible assets" to Total cost of revenue under the caption "Amortization of acquired technology" in the consolidated statements of operations. Our management believes this presentation aids in the comparability of our financial statements to industry peers. These reclassifications did not impact our operating income (loss), net income (loss) or earnings (loss) per share for any historical periods. These reclassifications also did not impact our consolidated balance sheets or consolidated statements of cash flows.

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These reclassifications resulted in $42.3 million recorded to Amortization of acquired technology within Total cost of revenue and a $42.3 million decrease to Amortization of acquired intangible assets within Total operating expenses in the year ended December 31, 2020. The increase to Total cost of revenue decreased our gross profit as a percentage of revenue ("gross margin") by approximately five percentage points.

These reclassifications resulted in $37.6 million recorded to Amortization of acquired technology within Total cost of revenue and a $37.6 million decrease to Amortization of acquired intangible assets within Total operating expenses in the year ended December 31, 2019. The increase to Total cost of revenue decreased our gross margin by approximately seven percentage points.

New Restructuring Initiative

On February 14, 2022, our Board of Directors approved a strategic restructuring program (the "2022 Restructuring Plan") to streamline the Company's operations in order to support the Company's investment in critical growth areas. The 2022 Restructuring Plan is expected to include, among other things, charges related to a consolidation of facilities and a workforce reduction. Any potential positions eliminated in countries outside the United States will be subject to local law and consultation requirements.

We currently expect to record approximately $20 million of restructuring and related expense associated with the 2022 Restructuring Plan, including approximately $6 million related to employee severance arrangements and approximately $14 million related to the facilities consolidation. We expect that the 2022 Restructuring Plan will be substantially completed in 2022.

Business Acquisitions

ECI Telecom Group Ltd.

On March 3, 2020 (the "ECI Acquisition Date"), we completed the acquisition of ECI Telecom Group Ltd. ("ECI") in accordance with the terms of the Agreement and Plan of Merger, dated as of November 14, 2019, by and among Ribbon, an indirect wholly-owned subsidiary of Ribbon ("Merger Sub"), Ribbon Communications Israel Ltd., ECI, and ECI Holding (Hungary) Kft, pursuant to which Merger Sub merged with and into ECI, with ECI surviving such merger as a wholly-owned subsidiary of Ribbon (the "ECI Acquisition"). Prior to the ECI Acquisition Date, ECI was a privately-held global provider of end-to-end packet-optical transport and software-defined networking ("SDN") and network function virtualization ("NFV") solutions for service providers, enterprises and data center operators. Ribbon believes the ECI Acquisition positions the Company for growth and enhances its competitive strengths by expanding its product portfolio beyond solutions primarily supporting voice applications to include data applications and optical networking.

As consideration for the ECI Acquisition, we issued the ECI shareholders and certain others 32.5 million shares of Ribbon common stock with a fair value of $108.6 million (the "Stock Consideration") and paid $322.5 million of cash, comprised of $183.3 million to repay ECI's outstanding debt, including both principal and interest, and $139.2 million paid to ECI's selling shareholders (the "Cash Consideration"). In addition, ECI shareholders received $33.4 million from the sale of certain of ECI's real estate assets. Cash Consideration was financed through cash on hand and committed debt financing consisting of a new $400 million term loan facility and new $100 million revolving credit facility, which was undrawn at the ECI Acquisition Date. The ECI Acquisition has been accounted for as a business combination and the financial results of ECI have been included in our consolidated financial statements for the periods subsequent to the ECI Acquisition Date.

Anova Data, Inc.

On February 28, 2019 (the "Anova Acquisition Date"), we acquired the business and technology assets of Anova Data, Inc. ("Anova"), a private company headquartered in Westford, Massachusetts (the "Anova Acquisition"). Anova is a provider of advanced analytics solutions and its next generation products provide a cloud-native, streaming analytics platform for network and subscriber optimization and monetization. The Company believes that the Anova Acquisition will reinforce and extend Ribbon's strategy to expand into network optimization, security and data monetization via big data analytics and machine learning.

As consideration for the Anova Acquisition, we issued 2.9 million shares of our common stock with a fair value of $15.2 million to Anova's sellers and equity holders on the Anova Acquisition Date and held back an additional 330,000 shares of our common stock with a fair value of $1.7 million (the "Deferred Purchase Consideration"), of which 316,551 shares were issued

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after post-closing adjustments on March 4, 2020. The Deferred Purchase Consideration was included as a component of Accrued expenses and other in our consolidated balance sheet at December 31, 2019. The Anova Acquisition has been accounted for as a business combination and the financial results of Anova have been included in our consolidated financial statements for the periods subsequent to the Anova Acquisition Date.

Sale of Kandy Communications Business and Investment in AVCT

On December 1, 2020 (the "Kandy Sale Date"), we completed the sale of our Kandy Communications Business to American Virtual Cloud Technologies, Inc. ("AVCT"). AVCT purchased the assets and assumed certain liabilities associated with the Kandy Communications Business, as well as all of the outstanding interests in Kandy Communications LLC, our subsidiary (the "Kandy Sale"). The assets acquired and liabilities assumed by AVCT in connection with the Kandy Sale were primarily comprised of accounts receivable, property and equipment, trade accounts payable and employee-related accruals.

As consideration, AVCT paid us $45.0 million, subject to certain adjustments, in the form of units of AVCT's securities (the "AVCT Units"), with each AVCT Unit consisting of: $1,000 in principal amount of AVCT’s Series A-1 convertible debentures (the “Debentures”); and (ii) one warrant to purchase 100 shares of AVCT common stock, $0.0001 par value (the “Warrants”), as consideration for the Kandy Sale. We received 43,778 AVCT Units as consideration on the Kandy Sale Date.

The Debentures bore interest at a rate of 10% per annum, which was being added to the principal amount of the Debentures. The entire principal amount of each Debenture, together with accrued and unpaid interest thereon, was due and payable on the earlier of the May 1, 2023 maturity date or the occurrence of a Change in Control as defined in the definitive purchase agreement, as amended (the "Amended Kandy Agreement"). Each Debenture was convertible, in whole or in part, at any time at our option into that number of shares of AVCT common stock, calculated by dividing the principal amount being converted, together with all accrued and unpaid interest thereon, by the applicable conversion price, which initially per share was $3.45. The Debentures were subject to mandatory conversion if the AVCT stock price was at or above $6.00 per share for 40 trading days in any 60 consecutive trading day period, subject to the satisfaction of certain other conditions. The conversion price was subject to customary adjustments including, but not limited to, stock dividends, stock splits and reclassifications. As of February 19, 2021, the stock price had traded above $6.00 for 40 days within a 60 consecutive trading day period, and accordingly, on September 8, 2021 (the "Debenture Conversion Date") upon the completion of customary regulatory filings by AVCT, the Debentures were converted into 13,700,421 shares of AVCT common stock (the "Debenture Shares").

The Warrants were independent of the Debentures and entitle us to purchase 4,377,800 shares of AVCT common stock at an exercise price of $0.01 per share. The Warrants were immediately exercisable on the Kandy Sale Date and expire on December 1, 2025. We had not exercised any of the Warrants as of December 31, 2021. We were also subject to a lock-up provision which limited our ability to sell any shares of the AVCT common stock underlying the AVCT Units prior to June 1, 2021 (the "Lock-Up Period"), except in certain transactions.

We determined that the AVCT Units had a fair value of $84.9 million at the Kandy Sale Date, comprised of the Debentures with a fair value of $66.3 million and the Warrants with a fair value of $18.6 million. The value of the net assets sold to AVCT totaled $1.3 million, resulting in a gain on the sale of $83.6 million. We calculated the fair value of the Debentures using a Lattice-based valuation approach, which utilizes a binomial tree to model the different paths the price of AVCT's common stock might take over the Debentures' life by using assumptions regarding the stock price volatility and risk-free interest rate. These results were then used to calculate the fair value of the Debentures at each measurement date prior to the Debenture Conversion Date. We used the Black-Scholes valuation model for estimating the fair value of the Warrants at each measurement date. The fair value of the Warrants was affected by AVCT's stock price as well as valuation assumptions, including the volatility of AVCT's stock price, expected term of the option, risk-free interest rate and expected dividends. Both the Lattice and Black-Scholes valuation models are based on available market data, giving consideration to all of the rights and obligations of each instrument and precluding the use of "blockage" discounts or premiums in determining the fair value of a large block of financial instruments. After the expiration of the Lock-Up Period and prior to the Debenture Conversion Date, we valued the AVCT Units at each measurement date by multiplying the closing stock price of AVCT common stock by the number of shares upon conversion of the Debentures and Warrants. At December 31, 2021, we valued the Debenture Shares and Warrants (the "AVCT Investment") by multiplying the closing stock price of AVCT common stock by the number of Debenture Shares and Warrants we held.

At December 31, 2021, the fair value of the AVCT Investment was $43.9 million, comprised of $33.3 million for the Debenture Shares and $10.6 million for the Warrants. We recorded a loss of $74.8 million in the year ended December 31, 2021 arising from the change in their aggregate fair value. This amount is included as a component of Other (expense) income, net, in our consolidated statement of operations. We recorded $3.5 million of interest income in the year ended December 31, 2021, respectively, which was added to the principal amount of the Debentures prior to the Debenture Conversion Date, and

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which is included in Interest expense, net, in our consolidated statement of operations. At December 31, 2020, the fair value of the AVCT Units was $115.2 million. The fair value of the AVCT Investment at December 31, 2021 and the AVCT Units at December 31, 2020 are reported as Investments in our consolidated balance sheets. The AVCT Investment is classified as a Level 1 fair value measurement at December 31, 2021 and the AVCT Units are classified as Level 2 fair value measurements within the fair value hierarchy at December 31, 2020.

We evaluated the nature of our investment in AVCT for the period from the Debenture Conversion Date through December 31, 2021 and determined that it represented an approximate 15% equity interest in AVCT on a diluted basis. Accordingly, we determined that we are not the primary beneficiary of AVCT as we do not have the power to direct the activities that most significantly impact the AVCT Investment's economic performance and therefore concluded that we had neither significant influence nor a controlling interest arising from the AVCT Investment.

Litigation Settlement

On April 22, 2019, we and Metaswitch Networks Ltd., Metaswitch Networks Corp and Metaswitch Inc. (collectively, "Metaswitch") agreed to a binding mediator's proposal that resolves the six previously disclosed lawsuits between the Company and Metaswitch (the "Lawsuits"). We and Metaswitch signed a Settlement and Cross-License Agreement on May 29, 2019 (the "Royalty Agreement"). Pursuant to the terms of the Royalty Agreement, Metaswitch agreed to pay us an aggregate amount of $63.0 million, which included cash payments of $37.5 million during the second quarter of 2019 and $25.5 million payable in three installments annually, beginning June 26, 2020, with such installment payments accruing interest at a rate of 4% per year. As part of the Royalty Agreement, we and Metaswitch have (i) released the other from all claims and liabilities; (ii) licensed each party's existing patent portfolio to the other party; and (iii) requested the applicable courts to dismiss the Lawsuits. We received $37.5 million of aggregate payments from Metaswitch in the second quarter of 2019 and recorded notes receivable for future payments of $25.5 million, comprised of $8.5 million in Other current assets and $17.0 million in Other assets in our consolidated balance sheet at December 31, 2019. We recorded the $63.0 million gain in Other (expense) income, net, in our consolidated statement of operations for the year ended December 31, 2019. We received $37.5 million of aggregate payments from Metaswitch in the second quarter of 2019 and $9.5 million, including $1.0 million of interest, in the second quarter of 2020.

On July 6, 2020, we and Metaswitch signed a First Supplemental Agreement to the Settlement and Cross-License Agreement (the "Supplemental Agreement") under which Metaswitch could elect to repay the outstanding amounts under the Royalty Agreement early in exchange for a reduction of $0.25 million to the outstanding principal, from $17.0 million to $16.75 million, and the payment of no further interest by Metaswitch effective June 26, 2020. We recorded the reduction to the outstanding principal as a reduction to interest income. On July 14, 2020, Metaswitch paid us the remaining outstanding balance of $16.75 million.

Operating Segments

Our chief operating decision maker (the "CODM") is our president and chief executive officer. Effective in the fourth quarter of 2020 and in connection with the ECI Acquisition, our CODM began to assess our performance based on the performance of two separate organizations within Ribbon: the Cloud and Edge operating segment ("Cloud and Edge") and the IP Optical Networks operating segment ("IP Optical Networks"). We previously operated in a single segment, as our CODM made decisions and assessed performance at the company level, and for periods prior to the ECI Acquisition, there are no financial results for IP Optical Networks to report.

Our Cloud and Edge operating segment provides secure and reliable software and hardware products, solutions and services for Voice over Internet Protocol ("VoIP") communications, Voice over Long-Term Evolution ("VoLTE") and Voice Over 5G ("VoNR") communications, and Unified Communications and Collaboration ("UC&C") services to both service provider and enterprise customers. Our Cloud and Edge products are increasingly software-centric and cloud-native for deployment on private, public or hybrid cloud infrastructures, in data centers, on enterprise premises and within service provider networks. Our Cloud and Edge product portfolio consists of our Session Border Controller ("SBC") products and our Network Transformation ("NTR") products.

Our IP Optical Networks operating segment provides high-performance, secure solutions for IP networking and optical transport, supporting wireless networks including 5G, metro and edge aggregation, core networking, data center interconnect, legacy network transformation and transport solutions for wholesale carriers. This portfolio is offered to service provider, enterprise and industry verticals with critical transport network infrastructures including utilities, government, defense, transportation, and education and research.

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Financial Overview

Financial Results

We reported a loss from operations of $117.8 million for 2021 and income from operations of $1.7 million for 2020. We reported a net loss of $177.2 million for 2021 and net income of $88.6 million for 2020.

Our revenue was $845.0 million in 2021, comprised of $556.7 million attributable to Cloud and Edge and $288.3 million attributable to IP Optical Networks. Our revenue was $843.8 million in 2020, comprised of $583.3 million attributable to Cloud and Edge and $260.5 million attributable to IP Optical Networks. Our gross profit was $444.7 million in 2021, comprised of $343.5 million attributable to Cloud and Edge and $101.2 million attributable to IP Optical Networks. Our gross profit was $450.8 million in 2020, comprised of $353.5 million attributable to Cloud and Edge and $97.4 million attributable to IP Optical Networks. Our gross margin was 52.6% in 2021 and 53.4% in 2020. In 2021, our Cloud and Edge gross margin was 61.7% and our IP Optical Networks gross margin was 35.1%. In 2020, our Cloud and Edge gross margin was 60.6% and our IP Optical Networks gross margin was 37.4%.

Our operating expenses were $562.5 million in 2021 and $449.1 million in 2020. Our 2021 operating expenses included $116.0 million for the impairment of goodwill, $28.3 million of amortization of acquired intangible assets, $7.6 million of acquisition-, disposal- and integration-related expense, and $11.7 million of restructuring and related expense. Our 2020 operating expenses included $18.6 million of amortization of acquired intangible assets, $17.2 million of acquisition-, disposal- and integration-related expense, and $16.2 million of restructuring and related expense.

We recorded stock-based compensation expense of $19.4 million in 2021 and $13.9 million in 2020.

See "Results of Operations" in this MD&A for additional discussion of our results of operations for the years ended December 31, 2021 and 2020.

Restructuring and Cost Reduction Initiatives

In 2020, we implemented a restructuring plan to eliminate certain positions and redundant facilities, primarily in connection with the ECI Acquisition, to further streamline our global footprint and improve our operations (the "2020 Restructuring Initiative"). In connection with this initiative, we have eliminated duplicate functions arising from the ECI Acquisition in support of our efforts to integrate the two companies. In connection with the 2020 Restructuring Initiative, we recorded restructuring and related expense of $4.7 million and $14.0 million in 2021 and 2020, respectively. The 2021 amount was comprised of $4.6 million for severance and related costs for approximately 60 employees and $0.1 million for variable and other facilities-related costs. The 2020 amount was comprised of $11.5 million for severance and related costs for approximately 190 employees, $2.0 million for variable and other facilities-related costs, and $0.5 million for accelerated amortization of lease assets. We expect these amounts will be fully paid in 2022. We expect to record additional restructuring and related expense approximating $1 million under the 2020 Restructuring Initiative in the aggregate for severance and planned facility consolidations.

In June 2019, we implemented a restructuring plan to further streamline our global footprint, improve our operations and enhance our customer delivery (the "2019 Restructuring Initiative"). The 2019 Restructuring Initiative includes facility consolidations, refinement of our research and development activities, and a reduction in workforce. The facility consolidations under the 2019 Restructuring Initiative (the "Facilities Initiative") include a consolidation of our North Texas sites into a single campus, housing engineering, customer training and support, and administrative functions, as well as a reduction or elimination of certain excess and duplicative facilities worldwide. In addition, we intend to substantially consolidate our global software laboratories and server farms into two lower cost North American sites. We continue to evaluate our properties included in the Facilities Initiative for accelerated amortization and/or right-of-use asset impairment. We expect that the actions under the Facilities Initiative will be completed in 2023.

In connection with the 2019 Restructuring Initiative, we recorded restructuring and related expense of $7.0 million and $2.3 million in 2021 and 2020, respectively. The amount recorded in 2021 was comprised of $5.7 million for variable and other facilities-related costs and $1.3 million of net expense for accelerated amortization of lease assets. The amount for accelerated amortization of lease assets was comprised of $3.4 million of expense and $2.1 million of income related to a lease modification for one of our restructured lease facilities. The amount recorded in 2020 was comprised of $0.5 million for severance and related costs for approximately 5 employees, $1.7 million for variable and other facilities-related costs and $0.1 million for accelerated amortization of lease assets. The amount accrued for severance and related costs was paid in 2021. We estimate that we will record nominal, if any, future expense related to this initiative.

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Accelerated rent amortization is recognized from the date that we commence the plan to fully or partially vacate a facility, for which there is no intent or ability to enter into a sublease, through the final vacate date. We recorded $3.4 million and $0.6 million of expense for accelerated rent amortization in the years ended December 31, 2021 and 2020, respectively. These amounts are included as components of Restructuring and related expense, and reduced our Operating lease right-of-use assets in our consolidated balance sheets at December 31, 2021 and 2020. We continue to evaluate our properties included in the Facilities Initiative for accelerated amortization and/or right-of-use asset impairment. We may incur additional future expense if we are unable to sublease other locations included in the Facilities Initiative.

Critical Accounting Policies and Estimates

Management's discussion and analysis of the financial condition and results of operations is based upon our consolidated financial statements, which have been prepared in accordance with accounting principles generally accepted in the United States of America. The preparation of these financial statements requires us to make estimates and judgments that affect the reported amounts of assets, liabilities, revenue and expenses, and related disclosure of contingent assets and liabilities. We base our estimates and judgments on historical experience, knowledge of current conditions and beliefs of what could occur in the future given available information. We consider the following accounting policies to be both those most important to the portrayal of our financial condition and those that require the most subjective judgment. If actual results differ significantly from management's estimates and projections, there could be a material effect on our consolidated financial statements. The significant accounting policies that we believe are the most critical include revenue recognition, the valuation of inventory, debentures and warrants received as sale consideration, warranty accruals, loss contingencies and reserves, stock-based compensation, business combinations, goodwill and intangible assets and accounting for income taxes.

Revenue Recognition. We derive revenue from two primary sources: products and services. Product revenue is generated from sales of our stand-alone software, as well as software with attached hardware that function together to deliver the products' essential functionality. Both software and hardware are also sold on a standalone basis. Services include customer support (software updates and technical support), consulting, design services, installation services and training. A typical contract includes both product and services. Generally, contracts with customers contain multiple performance obligations. For these contracts, we account for individual performance obligations separately if they are distinct. The transaction price is allocated to the separate performance obligations on a relative standalone selling price basis. SSPs are typically estimated based on observable transactions when these services are sold on a standalone basis.

The software licenses typically provide a perpetual right to use our software. We also sell term-based software licenses that expire and Software-as-as-Service ("SaaS")-based software, which are referred to as subscription arrangements. We do not customize our software nor are installation services required, as the customer has a right to utilize internal resources or a third-party service company. The software and hardware are delivered before related services are provided and are functional without professional services or customer support. We have concluded that our software licenses are functional intellectual property that are distinct, as the user can benefit from the software on its own. The product revenue is typically recognized upon transfer of control or when the software is made available for download, as this is the point that the user of the software can direct the use of, and obtain substantially all of the remaining benefits from, the functional intellectual property. We begin to recognize software revenue related to the renewal of subscription software licenses at the start of the subscription period.

Service revenue includes revenue from customer support and other professional services. We offer warranties on our products. Certain of our warranties are considered to be assurance-type in nature, ensuring that the product is functioning as intended. Assurance-type warranties do not represent separate performance obligations. We also sell separately-priced maintenance service contracts which qualify as service-type warranties and represent separate performance obligations. We do not allow and have no history of accepting product returns.

Customer support includes software updates on a when-and-if-available basis, telephone support, integrated web-based support and bug fixes or patches. We sell our customer support contracts at a percentage of list or net product price related to the support. Customer support revenue is recognized ratably over the term of the customer support agreement, which is typically one year.

Our professional services include consulting, technical support, resident engineer services, design services and installation services. Because control transfers over time, revenue is recognized based on progress toward completion of the performance obligation. The method to measure progress toward completion requires judgment and is based on the nature of the products or services to be provided. We generally use the input method to measure progress for our contracts because we believe it best depicts the transfer of assets to the customer which occurs as we incur costs for the contracts. However, in some instances, we use the output method because it best depicts the transfer of asset to the customer. Under the cost-to-cost measure of progress,

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the progress toward completion is measured based on the ratio of costs incurred to date to the total estimated costs at completion of the performance obligation. When the measure of progress is based upon expended labor, progress toward completion is measured as the ratio of labor time expended to date versus the total estimated labor time required to complete the performance obligation. Revenue is recorded proportionally as costs are incurred or as labor is expended. Costs to fulfill these obligations include internal labor as well as subcontractor costs.

We offer customer training courses, for which the related revenue is typically recognized as the training services are performed.

Our contracts with customers often include promises to transfer multiple products and services to the customer. Determining whether products and services are considered distinct performance obligations that should be accounted for separately versus together may require significant judgment.

Judgment is required to determine the SSP for each distinct performance obligation. In instances where SSP is not directly observable, such as when we do not sell the product or service separately, we determine the SSP using information that may include market conditions and other observable inputs. We typically have more than one SSP for individual products and services due to the stratification of those products and services by customers and circumstances. In these instances, the Company may use information such as the size of the customer and geographic region in determining the SSP.

Valuation of Inventory. We review inventory for both potential obsolescence and potential loss of value periodically. In this review, we make assumptions about the future demand for and market value of the inventory and, based on these assumptions, estimate the amount of any excess, obsolete or slow-moving inventory.

We write down our inventories if they are considered to be obsolete or at levels in excess of forecasted demand. In these cases, inventory is written down to estimated realizable value based on historical usage and expected demand. Inherent in our estimates of market value in determining inventory valuation are estimates related to economic trends, future demand for our products and technical obsolescence of our products. If future demand or market conditions are less favorable than our projections, additional inventory write-downs could be required and would be reflected in the cost of revenue in the period the revision is made. To date, we have not been required to revise any of our assumptions or estimates used in determining our inventory valuations.

We write down our evaluation equipment at the time of shipment to our customers, as it is not probable that the inventory value will be realizable.

Investments. We received Debentures and Warrants (collectively, the "AVCT Units") as consideration in connection with the Kandy Sale, which we accounted for in accordance with Accounting Standards Codification ("ASC") 820, Fair Value Measurement ("ASC 820"). We were subject to a lock-up provision which limited our ability to sell any shares of the AVCT common stock underlying the Debentures and the Warrants prior to June 1, 2021 (the "Lock-Up Period"), except in certain transactions. On September 8, 2021 (the "Debenture Conversion Date"), the Debentures were converted into 13,700,421 shares of AVCT common stock (the "Debenture Shares").

We calculated the fair value of the Debentures using a Lattice-based valuation approach, which utilizes a binomial tree to model the different paths the price of AVCT's common stock might take over the Debentures' life by using assumptions regarding the stock price volatility and risk-free interest rate. These results were then used to calculate the fair value of the Debentures at each measurement date. We used the Black-Scholes valuation model for estimating the fair value of the Warrants at each measurement date. The fair value of the Warrants was affected by AVCT's stock price as well as valuation assumptions, including the volatility of AVCT's stock price, expected term of the option, risk-free interest rate and expected dividends. Both the Lattice and Black-Scholes valuation models were based on available market data, giving consideration to all of the rights and obligations of each instrument and precluding the use of "blockage" discounts or premiums in determining the fair value of a large block of financial instruments. After the expiration of the Lock-Up Period and prior to the Debenture Conversion Date, the Company valued the AVCT Units at each measurement date by multiplying the closing stock price of AVCT common stock by the number of shares upon conversion of the Debentures and Warrants. Since the Debenture Conversion Date, the Company is valuing the Debenture Shares and Warrants by multiplying the closing stock price of AVCT common stock by the number of Debenture Shares and Warrants (collectively, the "AVCT Investment") it is holding at each measurement date. Adjustments to the fair values of the AVCT Units (prior to the Debenture Conversion Date) and AVCT Investment (subsequent to the Debenture Conversion Date) are included in Other (expense) income, net. The fair values of the AVCT Investment and the AVCT Units are reported as Investments in our consolidated balance sheets at December 31, 2021 and 2020, respectively.

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Warranty Accruals. We record warranty liabilities for estimated costs of fulfilling our obligations under standard limited hardware and software warranties at the time of sale. The liability for standard warranties is included in Accrued expenses and other and Other long-term liabilities in our consolidated balance sheet. The specific warranty terms and conditions vary depending upon the country in which we do business, but generally include material costs, technical support, labor and associated overhead over a period ranging from one to three years. We provide for the estimated costs to fulfill customer warranty obligations for certain of our products upon recognition of the related revenue. Warranty is included as a component of Cost of revenue in our consolidated statements of operations, and is determined based on actual warranty cost experience, estimates of component failure rates and our management's industry experience. Our sales contracts do not permit the right of return of the product by the customer after the product has been accepted.

Loss Contingencies and Reserves. We are subject to ongoing business risks arising in the ordinary course of business that affect the estimation process of the carrying value of assets, the recording of liabilities and the possibility of various loss contingencies. An estimated loss contingency is accrued when it is probable that a liability has been incurred or an asset has been impaired and the amount of loss can be reasonably estimated. We regularly evaluate current information available to determine whether such amounts should be adjusted and record changes in estimates in the period they become known. We are subject to various legal claims. We reserve for legal contingencies and legal fees when the amounts are probable and reasonably estimable.

Stock-Based Compensation. Our stock-based compensation cost is measured at the grant date based on the fair value of the award and is recognized as expense over the requisite service period, which is generally the vesting period.

We use the Black-Scholes valuation model for estimating the fair value on the date of grant of employee stock options. Determining the fair value of stock option awards at the grant date requires judgment regarding certain valuation assumptions, including the volatility of our stock price, expected term of the option, risk-free interest rate and expected dividends. Changes in such assumptions and estimates could result in different fair values and could therefore impact our earnings. Such changes, however, would not impact our cash flows. The fair value of restricted stock awards, restricted stock units and performance-based awards is based upon our stock price on the grant date.

We grant performance-based stock units, some of which include a market condition, to certain of our executives. We use a Monte Carlo simulation approach to model future stock price movements based upon the risk-free rate of return, the volatility of each entity, and the pair-wise covariance between each entity. These results are then used to calculate the grant date fair values of the performance-based stock units.

The amount of stock-based compensation expense recorded in any period for unvested awards requires estimates of the amount of stock-based awards that are expected to be forfeited prior to vesting, as well as assumptions regarding the probability that performance-based stock awards without market conditions will be earned.

Business Combinations. We allocate the purchase price of acquired companies to identifiable assets acquired and liabilities assumed at their acquisition date fair values. Goodwill as of the acquisition date is measured as the excess of consideration transferred over the net of the acquisition date fair values of the assets acquired and the liabilities assumed and represents the expected future economic benefits arising from other assets acquired in the business combination that are not individually identified and separately recognized. Significant management judgments and assumptions are required in determining the fair value of assets acquired and liabilities assumed, particularly acquired intangible assets which are principally based upon estimates of the future performance and cash flows expected from the acquired business and applied discount rates. While we use our best estimates and assumptions as part of the purchase price allocation process to accurately value assets acquired and liabilities assumed at a business combination date, our estimates and assumptions are inherently uncertain and subject to refinement. If different assumptions are used, it could materially impact the purchase price allocation and our financial position and results of operations. Any adjustments to assets acquired or liabilities assumed subsequent to the purchase price allocation period are included in operating results in the period in which the adjustments are determined. Intangible assets typically are comprised of in-process research and development, developed technology, customer relationships, trade names and internal use software.

Goodwill and Intangible Assets. Goodwill is not amortized, but instead is tested for impairment annually, or more frequently if indicators of potential impairment exist. Intangible assets with estimated lives and other long-lived assets are reviewed for impairment when events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of intangible assets with estimated lives and other long-lived assets is measured by comparing the carrying amount of the asset to future net undiscounted pretax cash flows expected to be generated by the asset. If these comparisons indicate that an asset is not recoverable, we will recognize an impairment loss for the amount by which the carrying value of the asset exceeds the related estimated fair value.

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Judgment is required in determining whether an event has occurred that may impair the value of goodwill, identifiable intangible assets or other long-lived assets. Factors that could indicate an impairment may exist include significant underperformance relative to plan or long-term projections, strategic changes in business strategy, significant negative industry or economic trends, a significant change in circumstances relative to a large customer, a significant decline in our stock price for a sustained period and a decline in our market capitalization to below net book value. We must make assumptions about future control premiums, market comparables, cash flows, operating plans, discount rates and other factors to determine recoverability.

Prior to 2020, our annual test for impairment of goodwill was completed as of November 30. Effective in 2020, we changed our annual goodwill impairment test date from November 30 to October 1. This change did not have a material impact on our consolidated financial statements.

As described above, effective in the fourth quarter of 2020, we determined that we had two operating segments: Cloud and Edge, and IP Optical Networks. For the purpose of testing goodwill for impairment, all goodwill is assigned to a reporting unit, which may be either an operating segment or a portion of an operating segment. We determined that the goodwill assigned to the Cloud and Edge reporting unit was $224.9 million and the goodwill assigned to the IP Optical Networks reporting unit was $192.0 million. We perform a fair value analysis using both an Income and Market approach, which encompasses a discounted cash flow analysis and a guideline public company analysis using selected multiples. We assess each valuation methodology based upon the relevance and availability of the data at the time the valuation is performed and the methodologies are weighted appropriately. Based on the results of our recently completed impairment test, we determined that the carrying value of our IP Optical Networks segment exceeded its fair value. We determined that the amount of the impairment was $116.0 million, and recorded an impairment charge in the fourth quarter of 2021. The impairment charge is reported separately in our consolidated statement of operations for the year ended December 31, 2021. We determined that there was no impairment of our Cloud and Edge segment. Upon completion of our 2020 annual test for goodwill impairment, we determined that there was no impairment of goodwill for either of our reporting units.

We previously operated as a single operating segment with one reporting unit and consequently we evaluated goodwill for impairment based on an evaluation of the fair value of the Company as a whole. Based on the results of our 2019 annual impairment test, we determined that our carrying value exceeded our fair value. We performed a fair value analysis using both an income and market approach as described above. We determined that the amount of the impairment was $164.3 million and recorded an impairment charge in the fourth quarter of 2019. The impairment charge is reported separately in our consolidated statement of operations for the year ended December 31, 2019.

Leases. We account for our leases in accordance with Accounting Standards Codification ("ASC") 842, Leases ("ASC 842"). We have operating and finance leases for corporate offices, research and development facilities, and certain equipment. Operating leases are reported separately in our consolidated balance sheets at December 31, 2021 and 2020. Assets acquired under finance leases are included in Property and equipment, net, in our consolidated balance sheets at December 31, 2021 and 2020.

We determine if an arrangement is a lease at inception. A contract is determined to contain a lease component if the arrangement provides us with a right to control the use of an identified asset. Lease agreements may include lease and non-lease components. In such instances for all classes of underlying assets, we do not separate lease and non-lease components but rather, account for the entire arrangement under leasing guidance. Leases with an initial term of 12 months or less are not recorded on the balance sheet and lease expense for these leases is recognized on a straight-line basis over the lease term.

For operating leases, lease expense for minimum fixed lease payments is recognized on a straight-line basis over the lease term. The expense for finance leases includes both interest and amortization expense components, with the interest component calculated based on the effective interest method and the amortization component calculated based on straight-line amortization of the right-of-use asset over the lease term. Lease contracts may contain variable lease costs, such as common area maintenance, utilities and tax reimbursements that vary over the term of the contract. Variable lease costs are not included in minimum fixed lease payments and as a result, are excluded from the measurement of the right-of-use assets and lease liabilities. We expense all variable lease costs as incurred.

Accounting for Income Taxes. Our provision for income taxes is comprised of a current and a deferred portion. The current income tax provision is calculated as the estimated taxes payable or refundable on tax returns for 2021. We provide for deferred income taxes resulting from temporary differences between financial and taxable income. Such differences arise primarily from tax net operating loss ("NOL") and credit carryforwards, depreciation, deferred revenue, stock-based compensation expense, accruals and reserves.

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We assess the recoverability of any tax assets recorded on the balance sheet and provide any necessary valuation allowances as required. In evaluating our ability to recover our deferred tax assets, we consider all available positive and negative evidence, including our past operating results, the existence of cumulative income in the most recent years, changes in the business in which we operate and our forecast of future taxable income. In determining future taxable income, we make assumptions, including the amount of state, federal and international pre-tax operating income, the reversal of temporary differences and the implementation of feasible and prudent tax planning strategies. These assumptions require significant judgment about the forecasts of future taxable income and are consistent with the plans and estimates we are using to manage our underlying businesses. Such assessment is completed on a jurisdiction-by-jurisdiction basis.

In 2021, we released a portion of the valuation allowances of $28 million on U.S. federal attributes, including certain U.S. federal net operating loss carryforwards. Thus, at December 31, 2021, we had valuation allowances of $472 million to offset deferred tax assets of $598 million. These remaining valuation allowances primarily relate to our U.S. and Israel operations. In the event we determine it is more likely than not that we will be able to use a deferred tax asset in the future in excess of its net carrying value, the valuation allowance would be reduced, thereby increasing net earnings and increasing equity in the period such determination is made. We have recorded net deferred tax assets in some of our other international subsidiaries. These amounts could change in future periods based upon our operating results and changes in tax law.

We have provided for income taxes on the undistributed earnings of our non-U.S. subsidiaries as of December 31, 2021, excluding Ireland and Israel. These subsidiaries, excluding Ireland and Israel, are cost-plus or limited risk distributors that are not anticipated to need to use excess funds locally. Accordingly, we are required to recognize and book deferred taxes for 2021. The deferred taxes are booked on the entire outside basis differences related to the foreign subsidiaries, the largest of these differences being undistributed earnings.

We assess all material positions taken in any income tax return, including all significant uncertain positions, in all tax years that are still subject to assessment or challenge by relevant taxing authorities. Assessing an uncertain tax position begins with the initial determination of the position's sustainability and is measured at the largest amount of benefit that has a greater than 50% likelihood of being realized upon ultimate settlement. As of each balance sheet date, unresolved uncertain tax positions must be reassessed, and we determine whether (i) the factors underlying the sustainability assertion have changed and (ii) the amount of recognized tax benefit is still appropriate. The recognition and measurement of tax benefits require significant judgment. Judgments concerning the recognition and measurement of a tax benefit might change as new information becomes available.

Results of Operations

Years Ended December 31, 2021 and 2020

Revenue. Revenue for the years ended December 31, 2021 and 2020 was as follows (in thousands, except percentages):

Year endedDecember 31, Increase (decrease)from prior year

Segment revenue for the years ended December 31, 2021 and 2020 was as follows (in thousands):

The decrease in our product revenue in 2021 compared to 2020 was primarily the result of $35 million of lower sales of our Cloud and Edge SBC products, coupled with the loss of $11 million of revenue due to the Kandy Sale. Supply chain and logistics issues, especially in the fourth quarter of 2021, impacted our ability to deliver products, accounting for $10 million of these lower sales and delaying these sales until 2022. These decreases were partially offset by $18 million of higher sales of

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our Cloud and Edge network transformation products and $12 million of IP Optical Networks products. The increase in revenue from the sale of IP Optical Networks products was attributable to a full year of revenue included in 2021, compared to ten months of revenue in 2020.

In 2021, 25% of our product revenue was attributable to sales to enterprise customers, compared to 30% in 2020. These sales were made through both our direct sales team and indirect sales channel partners. In 2021, 26% of our product revenue was from indirect sales through our channel partner program, compared to 29% in 2020.

The timing of the completion of customer projects and revenue recognition criteria satisfaction may cause our product revenue to fluctuate from one period to the next.

Service revenue is primarily comprised of software and hardware maintenance and support (“maintenance revenue”) and network design, installation and other professional services (“professional services revenue”).

Service revenue for the years ended December 31, 2021 and 2020 was comprised of the following (in thousands, except percentages):

Year endedDecember 31, Increasefrom prior year

Segment service revenue for the years ended December 31, 2021 and 2020 was comprised of the following (in thousands):

Total service revenue from our Cloud and Edge segment was relatively flat in 2021 compared to 2020. Service revenue from our IP Optical Networks segment increased by $16 million in 2021 compared to 2020. IP Optical Networks maintenance revenue and professional services revenue increased by $12 million and $4 million, respectively, in 2021 and 2020. This increase is primarily attributable to the inclusion of a full year of revenue in 2021, compared to 10 months of revenue in 2020.

The following customer contributed 10% or more of our revenue in the years ended December 31, 2021 and 2020:

Year endedDecember 31,

Verizon Communications Inc. 16% 15%

Revenue earned from customers domiciled outside the United States was 56% of revenue in 2021 and 55% of revenue in 2020. Due to the timing of project completions, we expect that the domestic and international components as a percentage of our revenue may fluctuate from quarter to quarter and year to year. Our total revenue for the years ended December 31, 2021 and 2020 was disaggregated geographically as follows (in thousands):

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Our deferred product revenue was $10 million at December 31, 2021 and $8 million at December 31, 2020. Our deferred service revenue was $120 million at December 31, 2021 and $115 million at December 31, 2020. Our deferred revenue balance may fluctuate as a result of the timing of revenue recognition, customer payments, maintenance contract renewals, contractual billing rights and maintenance revenue deferrals included in multiple element arrangements.

We expect that our total revenue in 2022 will increase modestly compared to our 2021 total revenue as our strategy to grow our IP Optical market share in North America gains momentum and capital spending in India and Israel increases.

Cost of Revenue/Gross Margin. Our cost of revenue consists primarily of amounts paid to third-party manufacturers for purchased materials and services, royalties, amortization of acquired technology, inventory valuation adjustments, warranty costs, and manufacturing and services personnel and related costs. Our cost of revenue, gross profit and gross margin for the years ended December 31, 2021 and 2020 were as follows (in thousands, except percentages):

Year endedDecember 31, Increase (decrease)from prior year

Cost of revenue:

Our segment cost of revenue, gross profit and gross margin for the years ended December 31, 2021 and 2020 were as follows (in thousands, except percentages):

Our gross margin decreased by one percentage point in 2021 compared to 2020. This decrease was primarily the result of higher component costs, expedite and production fees, and logistics expenses (collectively, "production costs") in both of our segments, coupled with product and customer mix, which decreased our gross margin by approximately two percentage points in the aggregate. This decrease was partially offset by the absence of costs related to our Kandy products as a result of the Kandy Sale, which increased our gross margin by approximately one percentage point.

The increase in our Cloud and Edge segment gross margin in 2021 compared to 2020 was primarily attributable to the absence of Kandy costs in the current year, partially offset by the aforementioned higher production costs in 2021. The decrease in our IP Optical segment gross margin in 2021 compared to 2020 was primarily attributable to the aforementioned higher production costs, partially offset by lower installation costs.

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We believe that our gross margin may decrease in 2022 compared to 2021 as a result of higher expected sales from IP Optical Networks, which has lower margins due to the higher hardware content in their products, and higher production costs resulting from ongoing worldwide supply chain issues.

Research and Development. Research and development ("R&D") expenses consist primarily of salaries and related personnel expenses and prototype costs for the design, development, testing and enhancement of our products. Research and development expenses for the years ended December 31, 2021 and 2020 were as follows (in thousands, except percentages):

Year endedDecember 31, Increasefrom prior year

Our research and development expenses were virtually flat in 2021 compared to 2020. Lower costs in our Cloud and Edge segment aggregated $25 million, primarily employee-related and product development costs, including the impact of the Kandy sale. These decreases were virtually offset by higher costs in our IP Optical Networks segment, primarily employee-related, product development and infrastructure -related expenses. These higher costs were primarily attributable to the inclusion of a full year of expenses in the current year, compared to ten months of expense in 2020, coupled with increased investment in our IP Optical Networks segment's product development.

Some aspects of our R&D efforts require significant short-term expenditures, the timing of which may cause significant variability in our expenses. We believe that rapid technological innovation is critical to our long-term success, and we are tailoring our investments to meet the requirements of our customers and market. We believe that our R&D expenses in 2022 will increase modestly compared to 2021, primarily due to our incremental investment in critical growth areas, partially offset by cost savings from the 2022 Restructuring Initiative.

Sales and Marketing. Sales and marketing expenses consist primarily of salaries and related personnel costs, commissions, travel and entertainment expenses, promotions, customer trial and evaluations inventory and other marketing and sales support expenses. Sales and marketing expenses for the years ended December 31, 2021 and 2020 were as follows (in thousands, except percentages):

Year endedDecember 31, Increasefrom prior year

The increase in sales and marketing expenses in 2021 compared to 2020 was primarily attributable to $7 million of higher employee-related expenses, $2 million of higher consulting fees, $1 million of higher infrastructure-related costs, and $1 million of net increases in other sales and marketing expenses.

At the segment level, our IP Optical Networks segment sales and market expenses increased by $15 million in 2021, partially offset by $4 million of lower Cloud and Edge segment expenses. The increase in IP Optical Networks segment expense is primarily attributable to the inclusion of a full year of expense in the current year, compared to ten months of expense in 2020, principally employee-related, consulting and infrastructure-related costs. The decrease in Cloud and Edge segment expense was primarily attributable to lower employee-related expenses resulting from the Kandy Sale.

We believe that our sales and marketing expenses 2022 will be consistent with 2021 levels.

General and Administrative. General and administrative expenses consist primarily of salaries and related personnel costs for executive and administrative personnel, and audit, legal and other professional fees. General and administrative expenses for the years ended December 31, 2021 and 2020 were as follows (in thousands, except percentages):

Year endedDecember 31, Decreasefrom prior year

The decrease in general and administrative expenses in the 2021 compared to 2020 was primarily attributable to $5 million of lower infrastructure-related expenses, $2 million each of lower employee- and litigation-related expenses, and $1 million of

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net decreases in other general and administrative expenses.

At the segment level, our Cloud and Edge segment expenses decreased by $8 million, while our IP Optical Networks segment expenses decreased by $2 million. The decrease in Cloud and Edge segment expenses was primarily attributable to lower infrastructure-related expense, the absence of approximately $2 million of litigation-related expense in the current year, and lower employee-related expenses and professional (i.e., consulting, legal and audit) fees. Lower infrastructure- and employee-related expenses for our IP Optical Networks segment were partially offset by higher general and administrative expenses resulting from the inclusion of a full year of expense in the current year, compared to ten months of expense in 2020.

We believe that our general and administrative expenses in 2022 will decrease slightly compared to our 2021 levels, primarily due to cost savings from the 2022 Restructuring Initiative.

Amortization of Acquired Intangible Assets included in Operating expenses. Amortization of acquired intangible assets included in Operating expenses for the years ended December 31, 2021 and 2020 was as follows (in thousands, except percentages):

Year endedDecember 31, Increasefrom prior year

The increase in amortization of acquired intangible assets included in operating expenses was primarily due to the inclusion of amortization expense related to the ECI Acquisition for a full year, compared to ten months of expense in 2020, coupled with the scheduled recognition of such expense in relation to expected future cash flows, as the amortization of such intangible assets is not recorded on a straight-line basis.

Impairment of Goodwill. Our annual testing for impairment of goodwill is completed as of October 1. Based on the results of our recently completed impairment test, we determined that the carrying value of our IP Optical Networks segment exceeded its fair value, and recorded an impairment charge of $116.0 million in the fourth quarter of 2021. We determined that there was no impairment of our Cloud and Edge segment. Our annual test for impairment in 2020 did not result in an impairment for either of our two reporting units. Impairment of goodwill is reported separately in the consolidated statements of operations.

Acquisition-, Disposal- and Integration-Related. Acquisition-, disposal- and integration-related expenses include those expenses related to acquisitions that we would otherwise not have incurred. Acquisition- and disposal-related expenses include professional and services fees, such as legal, audit, consulting, paying agent and other fees. Integration-related expenses represent incremental costs related to combining the Company's systems and processes with those of acquired businesses, such as third-party consulting and other third-party services. Acquisition-, disposal- and integration-related expenses are reported separately in the consolidated statements of operations.

We recorded $7.6 million of acquisition-, disposal- and integration-related expenses in 2021, comprised of $7.1 million of integration-related expenses, $0.3 million of disposal-related expenses an $0.2 million of acquisition-related expenses. We recorded $17.2 million of acquisition-, disposal- and integration-related expenses in 2020, comprised of $13.4 million of acquisition-related expenses, $1.9 million of disposal-related expenses and $1.8 million of integration-related expenses. The acquisition-related expenses primarily related to the ECI Acquisition and, to a lesser extent, other acquisition-related activities. The disposal-related expenses related to the Kandy Sale. The integration-related expenses related to our ongoing integration activities, primarily related to the ECI Acquisition.

Restructuring and Related. We have been committed to streamlining operations and reducing operating costs by closing and consolidating certain facilities and reducing our worldwide workforce. Please see the additional discussion of our restructuring initiatives in the "Restructuring and Cost Reduction Initiatives" section of the Overview of this Management's Discussion and Analysis of Financial Condition and Results of Operations. Restructuring and related expense is reported separately in the consolidated statements of operations.

We recorded restructuring and related expense of $11.7 million in 2021, comprised of $4.6 million for severance and related costs, and $7.1 million for variable and other facilities-related costs, including $1.3 million of net expense for the accelerated amortization of lease assets. We recorded $16.2 million of restructuring and related expense in 2020, comprised of $12.0 million for severance and related costs, and $4.2 million for variable and other facilities-related costs, including $0.6 million for the accelerated amortization of lease assets.

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Although we have eliminated positions as part of our restructuring initiatives, we continue to hire in certain areas that we believe are important to our future growth.

Interest Expense, net. Interest expense and interest income for the years ended December 31, 2021 and 2020 were as follows (in millions, except percentages):

Year endedDecember 31, Increase (decrease)from prior year

Interest income in 2021 primarily represents paid-in-kind interest on the Debentures prior to the Debenture Conversion Date, which was recorded as an increase to the fair value of the Debentures. Interest expense in 2021 was primarily comprised of $13.8 million of interest on our outstanding term debt and $4.8 million in the aggregate related to amortization of debt issuance costs in connection with the 2020 Credit Facility (as defined below), including the write-off of $2.5 million of capitalized debt issuance costs in connection with the Third Amendment (as defined below), and interest expense in connection with the factoring of certain accounts receivable.

Interest income in 2020 primarily represents interest earned on the outstanding note receivable from Metaswitch, which was paid in full in the third quarter of 2020. Interest expense in 2020 was primarily comprised of $14.4 million of interest on our outstanding term debt, and $4.2 million in the aggregate related to amortization of debt issuance costs, interest on other borrowings and finance leases, and interest expense in connection with the factoring of certain accounts receivable. Interest expense in 2020 also included the write-off of $2.9 million of debt issuance costs in connection with the amendment of the 2020 Credit Facility and the retirement of the 2019 Credit Facility (as defined below).

Other (Expense) Income, Net. We recorded other expense, net, aggregating $74.5 million in 2021, primarily comprised of $74.8 million of losses resulting from the change in fair value of the AVCT Units for the period from January 1, 2021 to the Debenture Conversion Date and the AVCT Investment for the period from the Debenture Conversion Date to December 31, 2021. This loss was partially offset by a gain of $2.8 million on the sale of our QualiTech business, which operates compliance testing laboratories in Israel for reliability and standardization testing for the high-tech industry, including testing in medical equipment, military equipment and vehicles ("QualiTech"). We recorded $112.7 million of net other income in 2020, primarily in connection with the Kandy Sale, which was comprised of $83.6 million from the gain on the sale, and $30.3 million related to the increase in the fair value of the AVCT Units from the Kandy Sale Date through December 31, 2020.

Income Tax Benefit (Provision). We recorded an income tax benefit of $31.0 million in 2021 and an income tax provision of $4.7 million in 2020. The benefit recorded in 2021 was primarily the result of the release of part of the valuation allowance against deferred tax assets in the U.S. and a reduction in the deferred taxes on the undistributed earnings of non-U.S. subsidiaries due to legal entity restructuring activities. The provision recorded in 2020 was primarily the result of the gain from the Kandy Sale and foreign operations.

During 2021 and 2020, we performed an analysis to determine if, based on all available evidence, we considered it more likely than not that some portion or all of the recorded deferred tax assets will not be realized in a future period. As a result of our evaluations, in 2021, we released a portion of the valuation allowance on U.S. federal net operating loss carryforwards of $28 million. As a result, for the U.S. deferred tax assets, we concluded that deferred tax assets are generally realizable, with the exception of certain federal and state net operating loss carryforwards, as well as certain tax credits, that are not anticipated to be utilized. Accordingly, we have maintained a valuation allowance on our U.S. deferred tax assets of $30.5 million. As a result of our evaluations for Israel, we maintained a valuation against our deferred tax assets in Israel.

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Liquidity and Capital Resources

Our consolidated statements of cash flows are summarized as follows (in thousands):

Year endedDecember 31,

We had cash and restricted cash aggregating $106.5 million and $135.7 million at December 31, 2021 and 2020, respectively. We had cash held by our non-U.S. subsidiaries aggregating approximately $60 million and $46 million at December 31, 2021 and 2020, respectively. If we elect to repatriate all of the funds held by our non-U.S. subsidiaries as of December 31, 2021, we do not believe that the amounts of potential withholding taxes that would arise from the repatriation would have a material effect on our liquidity.

On April 29, 2019, we, as guarantor, and Ribbon Communications Operating Company, Inc., as borrower, entered into a syndicated, amended and restated credit facility (the "2019 Credit Facility"), which replaced our previous credit facility, which we had entered into in 2018. The 2019 Credit Facility provided for a $50 million term loan facility that was advanced in full on April 29, 2019, and a $100 million revolving line of credit.

We currently maintain the Senior Secured Credit Facilities Credit Agreement (as amended, the "2020 Credit Facility"), which we entered into on March 3, 2020, by and among us, as a guarantor, Ribbon Communications Operating Company, Inc., as the borrower ("Borrower"), Citizens Bank, N.A. ("Citizens"), as administrative agent, a lender, issuing lender, swingline lender, joint lead arranger and bookrunner, Santander Bank, N.A., as a lender, joint lead arranger and bookrunner, and the other lenders party thereto (each, together with Citizens Bank, N.A. and Santander Bank, N.A., referred to individually as a "Lender", and collectively, the "Lenders"). For additional details regarding the terms of the 2020 Credit Facility, see Note 10 to our consolidated financial statements. The proceeds from the 2020 Credit Facility were used, in part, to pay off in full all obligations of the Company under the 2019 Credit Facility.

The 2020 Credit Facility provides for $500 million of commitments from the lenders to the Borrower, comprised of $400 million in term loans (the "2020 Term Loan Facility") and a $100 million facility available for revolving loans (the "2020 Revolving Credit Facility"). Under the 2020 Revolving Credit Facility, a $30 million sublimit is available for letters of credit and a $20 million sublimit is available for swingline loans. Under the 2020 Credit Facility, we were originally required to make quarterly principal payments aggregating approximately $10 million in the first year, $20 million per year for the following three years and $30 million in the last year, with the remaining balance due on the maturity date.

The indebtedness and other obligations under the 2020 Credit Facility are unconditionally guaranteed on a senior secured basis by the Company, Edgewater Networks, Inc., a wholly-owned subsidiary of the Company, and GENBAND Inc., a wholly-owned subsidiary of the Company (together, the "Guarantors"). The 2020 Credit Facility is secured by first-priority liens on substantially all of the assets of the Borrower and the Guarantors, including substantially all of the assets of the Company.

The 2020 Credit Facility requires compliance with certain financial covenants, including a minimum Consolidated Fixed Charge Coverage Ratio and a maximum Consolidated Net Leverage Ratio (each as defined in the 2020 Credit Agreement, and each tested on a quarterly basis).

In addition, the 2020 Credit Facility contains various covenants that, among other restrictions, limit our and our subsidiaries’ ability to incur or assume indebtedness; grant or assume liens; make acquisitions or engage in mergers; sell, transfer, assign or convey assets; repurchase equity and make dividend and certain other restricted payments; make investments; engage in transactions with affiliates; enter into sale and leaseback transactions; enter into burdensome agreements; change the nature of its business; modify their organizational documents; or amend or make prepayments on certain junior debt.

The 2020 Credit Facility contains events of default that are customary for a secured credit facility. If an event of default relating to bankruptcy or other insolvency events with respect to the Company or any of its subsidiaries occurs, all obligations

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under the 2020 Credit Facility will immediately become due and payable. If any other event of default exists under the 2020 Credit Facility, the lenders can accelerate the maturity of the obligations outstanding under the 2020 Credit Facility and exercise other rights and remedies, including charging a default rate of interest equal to 2.00% per year above the rate that would otherwise be applicable. In addition, if any event of default exists under the 2020 Credit Facility, the lenders can commence foreclosure or other actions against the collateral.

On August 18, 2020 (the "First Amendment Effective Date"), we entered into the First Amendment to the 2020 Credit Facility. Pursuant to an assignment and assumption agreement entered into by Citizens and certain affiliates of Whitehorse Capital on the First Amendment Effective Date (collectively, "HIG Whitehorse"), and consented to by Citizens and the Borrower, $75 million of the 2020 Term Loan Facility, designated as the Term B Loan (the "Term B Loan") was assigned from Citizens to HIG Whitehorse. The remaining $325 million of the 2020 Term Loan Facility that was not assigned to HIG Whitehorse was deemed the Term A Loan (the "Term A Loan" and, together with the Term B Loan, the "Amended 2020 Term Loan Facility").

The Term A Loan and amounts under the 2020 Revolving Credit Facility mature in March 2025. The Term A Loan and 2020 Revolving Credit Facility bear interest at the Borrower's option at either the LIBOR rate plus a margin ranging from 1.50% to 3.50% per year, or the base rate (the highest of the Federal Funds Effective Rate (as defined in the 2020 Credit Agreement) plus 0.50%, or the prime rate announced from time to time in The Wall Street Journal) plus a margin ranging from 0.50% to 2.50% per year (the "Applicable Margin"). The Applicable Margin varies depending on our Consolidated Net Leverage Ratio (as defined in the 2020 Credit Agreement). The base rate and the LIBOR rate are each subject to a zero percent floor. We are required to make quarterly principal payments on the Term A Loan aggregating approximately $10 million in the first year, $16 million in each of the next two years, $20 million in the fourth year and $16 million in the last year, with the final payment approximating $244 million due on the maturity date. The Borrower can prepay all amounts under the Term A Loan and the 2020 Revolving Credit Facility at any time without premium or penalty (other than customary LIBOR breakage costs), subject to certain notice requirements. The First Amendment did not change the terms applied to the Term A Loan or the Revolving Credit Facility under the 2020 Credit Facility.

The Term B Loan was scheduled to mature in March 2026 and bore interest, at the Borrower's option, at either the LIBOR rate plus a margin of 7.50% per year, or the base rate (the highest of the Federal Funds Effective Rate (as defined in the 2020 Credit Facility) plus 0.50%, or the prime rate announced from time to time in The Wall Street Journal, plus a margin of 6.50% per year. The Term B Loan had a lower rate of amortization than the Term A Loan and was subject to a 1.0% premium if voluntarily repaid in connection with a repricing transaction (as defined in the First Amendment) occurring prior to the six month anniversary of the First Amendment Effective Date. We were required to make quarterly principal payments totaling approximately $1 million in the first year and $8 million in the aggregate over the next four and a half years, with the final payment approximating $66 million due on the maturity date.

The First Amendment reduced the Borrower's ability to incur new tranches of term loans, or increases in commitments under the Amended 2020 Term Loan Facility or the 2020 Revolving Credit Facility. Specifically, such indebtedness can be incurred up to an aggregate dollar amount equal to 75% of the Company's Consolidated Adjusted EBITDA (as defined in the 2020 Credit Facility), reduced from 100% prior to the First Amendment, as of the most recently ended fiscal quarter for which financial statements have been delivered to the lenders, plus additional amounts, so long as the Borrower's Consolidated Net Leverage Ratio (as defined in the 2020 Credit Facility) does not exceed 2.25:1.00, reduced from 2.75:1.00 prior to the First Amendment. The First Amendment also reduced the amount of Unrestricted Cash (as defined in the 2020 Credit Facility) used in calculating the Borrower's Consolidated Net Leverage Ratio from $25 million to $10 million.

On December 1, 2020, we entered into a Second Amendment to the 2020 Credit Facility to obtain consent for an equity exchange with AVCT in connection with the Kandy Sale, as well as amend certain provisions of the 2020 Credit Facility.

At December 31, 2020, we had an outstanding Term A Loan balance of $318.5 million at an average interest rate of 3.4%, and the Term B Loan had an outstanding balance of $74.6 million at average interest rate of 8.40%. The 2020 Revolving Credit Facility did not have an outstanding balance but had $5.6 million of letters of credit outstanding with an interest rate of 2.5%.

On March 3, 2021 (the "Third Amendment Effective Date"), we entered into a Third Amendment to Credit Agreement (the "Third Amendment"), which further amended the 2020 Credit Facility. The Third Amendment provided for an incremental term loan facility to us in the original principal amount of $74.6 million, the proceeds of which were used on the Third Amendment Effective Date to consummate an open market purchase of all outstanding amounts under the Term B Loan. Upon the consummation of the open market purchase, the Term B Loans were assigned to the Borrower and immediately canceled, such that the outstanding amount under the Term A Loan and incremental term loan facility were combined and held by the Lenders (the "2020 Term Loan"). We are required to make quarterly principal payments on the 2020 Term Loan aggregating

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approximately $20 million per year in the first three years and $30 million in the fourth year, with the final payment approximating $300 million due on the maturity date.

On March 10, 2022, we entered into a Fourth Amendment to the 2020 Credit Facility (the "Fourth Amendment") to increase the Maximum Consolidated Net Leverage Ratio (as defined in the 2020 Credit Facility) to 4.25:1.00 for the first quarter of 2022 and 4.50:1.00 for the second quarter of 2022, with reductions in subsequent quarters through the third quarter of 2023, when the ratio will be fixed at 3.00:1.00. In connection with the Fourth Amendment, we made a $15.0 million prepayment that was applied to the final payment due on the maturity date.

At December 31, 2021, we had an outstanding 2020 Term Loan balance of $375.5 million at an average interest rate of 3.4% and $4.3 million of letters of credit outstanding with an interest rate of 2.5%. We were in compliance with all covenants of the 2020 Credit Facility at both December 31, 2021 and 2020.

We are exposed to financial market risk related to foreign currency fluctuations and changes in interest rates. These exposures are actively monitored by management. To manage the volatility related to the exposure to changes in interest rates, we have entered into a derivative financial instrument. Management's objective is to reduce, where it is deemed appropriate to do so, fluctuations in earnings and cash flows associated with changes in interest rates. Our policies and practices are to use derivative financial instruments only to the extent necessary to manage exposures. We do not hold or issue derivative financial instruments for trading or speculative purposes.

As a result of exposure to interest rate movements, during March 2020, we entered into an interest rate swap arrangement, which effectively converted our $400 million term loan with its variable interest rate based upon one-month LIBOR to an aggregate fixed rate of 0.904%, plus a leverage-based margin as defined in the 2020 Credit Facility. The notional amount of this swap as of December 31, 2021 was $400 million, and the swap matures on March 3, 2025, the same date the 2020 Credit Facility matures.

Our objectives in using interest rate derivatives are to add stability to interest expense and to manage our exposure to interest rate movements. To accomplish this objective, we are using an interest rate swap as part of our interest rate risk management strategy. Interest rate swaps designated as cash flow hedges involve the receipt of variable amounts from a counterparty in exchange for making fixed-rate payments over the life of the agreements without exchange of the underlying notional amount.

The effective portion of changes in the fair value of derivatives designated and that qualify as cash flow hedges is recorded in accumulated other comprehensive income (loss) in the consolidated balance sheet and is subsequently reclassified into earnings in the period that the hedged forecasted transactions affect earnings. During the years ended December 31, 2021 and 2020, such a derivative was used to hedge the variable cash flows associated with the 2020 Credit Facility. Any ineffective portion of the change in fair value of the derivative would be recognized directly in earnings. However, during the years ended December 31, 2021 and 2020, we recorded no hedge ineffectiveness.

Amounts reported in accumulated other comprehensive income (loss) related to our derivative are reclassified to interest expense as interest is accrued on our variable-rate debt. Based upon projected forward rates, we estimate as of December 31, 2021 that $2.1 million may be reclassified as an increase to interest expense over the next 12 months.

We use letters of credit, performance and bid bonds in the course of our business. At December 31, 2021, we had $30.1 million of letters of credit, bank guarantees, performance and bid bonds outstanding (collectively, the "Guarantees"), comprised of the $4.3 million of letters of credit under the 2020 Credit Facility described above (the "Letters of Credit") and $25.8 million of bank guarantees and performance and bid bonds under various uncommitted facilities (collectively, the "Other Guarantees"). At December 31, 2020, we had $32.6 million of Guarantees, comprised of $5.6 million of Letters of Credit and $27.0 million of Other Guarantees. At December 31, 2021 and 2020, we had cash collateral of $2.6 million and $2.7 million, respectively, supporting the Guarantees under our uncommitted facilities. This cash collateral is included in Restricted cash in our consolidated balance sheets at December 31, 2021 and 2020.

Our IP Optical Networks segment maintains customer receivables factoring agreements with a number of financial institutions. Under the terms of these agreements, we may transfer receivables to the financial institutions, on a non-recourse basis, provided that the financial institutions approve the receivables in advance. During the year ended December 31, 2021, we received $118.5 million of cash from the sale of certain accounts receivable and recorded $0.8 million of interest expense in connection with these transactions. During the year ended December 31, 2020, we received $119.8 million of cash from the sale of certain accounts receivable and recorded $0.9 million of interest expense in connection with these transactions.

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In the second quarter of 2019, our Board approved a stock repurchase program (the "Repurchase Program") pursuant to which we could repurchase up to $75 million of our common stock prior to April 18, 2021. The Company did not repurchase any common stock in the year ended December 31, 2020 or in the period from January 1, 2021 though the expiration of the Repurchase Program on April 18, 2021.

We have no off-balance sheet arrangements that have or are reasonably likely to have a current or future material effect on our financial position, changes in financial position, revenue or expenses, results of operations, liquidity, capital expenditures or capital resources.

Cash Flows from Operating Activities

Our primary source of cash from operating activities has been from cash collections from our customers. We expect cash flows from operating activities to be affected by increases and decreases in sales volumes and timing of collections, and by purchases and shipments of inventory. Our primary uses of cash from operating activities have been for personnel costs and investment in our research and development and in our sales and marketing, and general and administrative departments.

Our operating activities provided $19 million of cash in 2021, primarily the result of higher accounts payable and deferred revenue, and lower other operating assets, coupled with our non-cash operating expenses such as the impairment of goodwill, the decrease in the fair value of the AVCT Investment, amortization of intangible assets, stock-based compensation and depreciation. These amounts were partially offset by our net loss and a non-cash gain arising from the reversal of portions of our deferred tax asset, coupled with lower accrued expenses and other long-term liabilities and higher accounts receivable and inventory. The decrease in accrued expenses and other long-term liabilities was primarily due to employee-related cash payments and payments related to facilities, professional fees and royalties.

Our operating activities provided $102 million of cash in 2020, primarily the result of our net income, lower other operating assets, inventory and accounts receivable, higher accrued expenses and other long-term liabilities, and our non-cash operating income and expenses such as the gain on the Kandy Sale, amortization of intangible assets, stock-based compensation, depreciation, and amortization of debt issuance costs. These amounts were partially offset by lower accounts payable and deferred revenue. The decrease in other operating assets was primarily due to the payments received from Metaswitch aggregating $26 million in connection with the 2019 litigation settlement and subsequent supplemental agreement to accelerate the payment of amounts outstanding. The increase in accrued expenses and other long-term liabilities was primarily due to the derivative liability we recorded in connection with our interest rate swap, which we entered into in the first quarter of 2020.

Cash Flows from Investing Activities

Our investing activities used $14 million and $330 million of cash in 2021 and 2020, respectively. Our 2021 investing activities were comprised of $17 million paid for purchases of property and equipment, partially offset by $3 million of proceeds from the sale of QualiTech. Our 2020 investing activities were comprised of $347 million of cash paid as cash consideration for ECI and $26 million paid for purchases of property and equipment, partially offset by $43 million of cash proceeds from the sale of land in connection with the ECI Acquisition.

Cash Flows from Financing Activities

Our financing activities used $34 million of cash in 2021. We received $75 million of proceeds from the incremental loan obtained in connection with the Third Amendment, which amount was used to consummate an open market purchase of all outstanding amounts under the Term B Loan. We used $92 million for principal payments of term debt, including the $75 million payoff of the Term B Loan in connection with the Third Amendment, $14 million for the payment of tax withholding obligations related to the net share settlement of restricted stock awards upon vesting, and $1 million each for principal payments of finance leases and payments of debt issuance costs.

Our financing activities provided $319 million of cash in 2020, primarily due to $479 million of proceeds from term debt, which was comprised of $400 million from the 2020 Credit Facility, $75 million from the Term B Loan under the Amended 2020 Credit Facility (concurrent with the repayment of the same amount of original debt under the 2020 Credit Facility as noted below) and $4 million of proceeds from short-term loans in China for the financing of certain export activities. These proceeds were partially offset by the repayment of the $75 million of debt that was extinguished in connection with the First Amendment, the repayment of $57 million outstanding under the 2019 Credit Facility (comprised of $8 million under the revolving credit facility and $49 million of long-term debt), the payment of $14 million of debt issuance costs in connection with the 2020 Credit Facility and the First Amendment, and the repayment of principal aggregating $10 million related to the

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2020 Credit Facility and short-term loans in China. We also paid $2 million for withholding obligations related to the net share settlement of restricted stock awards upon vesting and $1 million for principal payments on finance leases.

Based on our current expectations, we believe our current cash and available borrowings under the 2020 Credit Facility will be sufficient to meet our anticipated cash needs for working capital and capital expenditures for at least twelve months. The rate at which we consume cash is dependent on the cash needs of our future operations, including our contractual obligations at December 31, 2021, primarily comprised of our debt principal and interest obligations as described above, and our operating lease and purchase obligations. Our operating lease obligations totaled $88 million at December 31, 2021, with payments aggregating $21 million in 2022, $18 million in 2023, $11 million in 2024 and $38 million thereafter. Our purchase obligations totaled $167 million at December 31, 2021, with estimated payments aggregating $139 million in 2022 and $28 million thereafter. We anticipate devoting substantial capital resources to continue our research and development efforts, to maintain our sales, support and marketing, to complete acquisition-related integration activities and for other general corporate activities. We further believe that our financial resources, along with managing discretionary expenses, will allow us to manage the ongoing impact of the COVID-19 pandemic on our business operations. Looking ahead, we have developed contingency plans to reduce costs further if the situation continues to deteriorate. The challenges posed by the COVID-19 pandemic on our business continue to evolve rapidly. Consequently, we continue to evaluate our financial position in light of future developments, particularly those relating to the COVID-19 pandemic. However, it is difficult to predict future liquidity requirements with certainty, and our cash and available borrowings under the 2020 Credit Facility may not be sufficient to meet our future needs, which would require us to refinance our debt and/or obtain additional financing. We may not be able to refinance our debt or obtain additional financing on favorable terms or at all.

Recent Accounting Pronouncements

In December 2019, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes ("ASU 2019-12"), which modifies Accounting Standards Codification ("ASC") 740, Income Taxes (Topic 740), to simplify the accounting for income taxes. ASU 2019-12 addresses the accounting for hybrid tax regimes, tax basis step-up in goodwill obtained in a transaction that is not a business combination, separate financial statements of legal entities not subject to tax, intraperiod tax allocation exception to incremental approach, ownership changes in investments - changes from a subsidiary to an equity method investment, ownership changes in investments - changes from an equity method investment to a subsidiary, interim period accounting for enacted changes in tax law and year-to-date loss limitation in interim period tax accounting. The adoption of ASU 2019-12 did not have a material impact on our consolidated financial statements upon adoption.

In October 2021, the FASB issued ASU 2021-08, Business Combinations (Topic 805): Accounting for Contract Assets and Contract Liabilities from Contracts with Customers ("ASU 2021-08"), which amends ASC 805, Business Combinations (Topic 805), to add contract assets and contract liabilities to the list of exceptions to the recognition and measurement principles that apply to business combinations and to require that an acquiring entity recognize and measure contract assets and contract liabilities acquired in a business combination in accordance with ASC 606, Revenue from Contracts with Customers (Topic 606) ("ASC 606"). Under current GAAP, an acquirer generally recognizes such items at fair value on the acquisition date. While primarily related to contract assets and contract liabilities that were accounted for by the acquiree in accordance with ASC 606, ASU 2021-08 also applies to contract assets and contract liabilities from other contracts to which the provisions of ASC 606 apply, such as contract liabilities from the sale of nonfinancial assets within the scope of ASU 2017-05, Other Income - Gains and Losses from the Derecognition of Nonfinancial Assets (Subtopic 610-20). ASU 2021-08 is effective for the Company January 1, 2023, with early adoption permitted. We believe that the adoption of ASU 2021-08 could have a material impact on our consolidated financial statements for periods including and subsequent to significant business acquisitions.

In January 2021 the FASB issued ASU 2021-01, Reference Rate Reform (Topic 848): Scope ("ASU 2021-01"), which refines the scope of ASC 848, Reference Rate Reform, and clarifies some of its guidance as part of the FASB's monitoring of global reference rate reform activities. ASU 2021-01 permits entities to elect certain optional expedients and exceptions when accounting for derivative contracts and certain hedging relationships affected by changes in the interest rates used for discounting cash flows, for computing variation margin settlements, and for calculating price alignment interest in connection with reference rate reform activities under way in global financial markets (the "discounting transition"). ASU 2021-01 is effective for the Company prospectively in any period through December 31, 2022 that a modification is made to the terms of the derivatives affected by the discounting transition. We do not believe the adoption of ASU 2021-01 will have a material impact on our consolidated financial statements.

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Item 7A. Quantitative and Qualitative Disclosures About Market Risk

We are exposed to a variety of market risks, changes in interest rates affecting the return on our investments and foreign currency fluctuations.

To manage the volatility related to the exposure to changes in interest rates, we have entered into a derivative financial instrument. Our objective is to reduce, where it is deemed appropriate to do so, fluctuations in earnings and cash flows associated with changes in interest rates. Our policies and practices are to use derivative financial instruments only to the extent necessary to manage exposures. We do not hold or issue derivative financial instruments for trading or speculative purposes.

Amounts reported in accumulated other comprehensive income (loss) related to our derivative are reclassified to interest expense as interest is accrued on our variable-rate debt. Our derivative had a fair value of $1.8 million at December 31, 2021, comprised of $2.1 million included in Accrued expenses and other and $3.9 million included in Other assets on our consolidated balance sheet. Based upon projected forward rates, we estimate as of December 31, 2021 that $2.1 million may be reclassified as an increase to interest expense over the next twelve months.

At December 31, 2021, we had outstanding debt totaling $375.5 million. A hypothetical movement of plus or minus 50 basis points in the interest rate of our outstanding debt would have changed our interest expense by approximately $2 million for the year ended December 31, 2021.

Based on a hypothetical 10% adverse movement in all foreign currency exchange rates, our revenue and net loss for the year ended December 31, 2021 would have been adversely affected by approximately $25 million and $11 million, respectively, although the actual effects could differ materially from this hypothetical analysis.

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Item 8. Financial Statements and Supplementary Data

Report of Independent Registered Public Accounting Firm (PCAOB ID No. 34) 58

Consolidated Balance Sheets as of December 31, 2021 and 2020 61

Notes to Consolidated Financial Statements 67

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REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

To the Stockholders and the Board of Directors of Ribbon Communications Inc.

Opinion on the Financial Statements

We have audited the accompanying consolidated balance sheets of Ribbon Communications Inc. and subsidiaries (the "Company") as of December 31, 2021 and 2020, the related consolidated statements of operations, comprehensive income (loss), stockholders' equity, and cash flows for each of the three years in the period ended December 31, 2021, and the related notes (collectively referred to as the "financial statements"). In our opinion, the financial statements present fairly, in all material respects, the financial position of the Company as of December 31, 2021 and 2020, and the results of its operations and its cash flows for each of the three years in the period ended December 31, 2021, in conformity with accounting principles generally accepted in the United States of America.

We have also audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the Company's internal control over financial reporting as of December 31, 2021, based on criteria established in Internal Control - Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission and our report dated March 11, 2022, expressed an unqualified opinion on the Company's internal control over financial reporting.

Basis for Opinion

These financial statements are the responsibility of the Company's management. Our responsibility is to express an opinion on the Company's financial statements based on our audits. We are a public accounting firm registered with the 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 audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. Our audits included performing procedures to assess the risks of material misstatement of the 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 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 financial statements. We believe that our audits provide a reasonable basis for our opinion.

Critical Audit Matters

The critical audit matters communicated below are matters arising from the current-period audit of the financial statements that were communicated or required to be communicated to the audit committee and that (1) relate to accounts or disclosures that are material to the financial statements and (2) involved our especially challenging, subjective, or complex judgments. The communication of critical audit matters does not alter in any way our opinion on the financial statements, taken as a whole, and we are not, by communicating the critical audit matters below, providing separate opinions on the critical audit matters or on the accounts or disclosures to which they relate.

Revenue Recognition — Refer to Notes 2 and 16 to the financial statements

Critical Audit Matter Description

The Company recognizes revenue from two primary sources: products and services. Generally, contracts with customers contain multiple performance obligations, consisting of products and services. For these contracts, the Company accounts for individual performance obligations separately if they are considered distinct. When an arrangement contains more than one performance obligation, the Company will allocate the transaction price to each performance obligation on a relative standalone selling price basis. The Company utilizes the observable price of goods and services when they are sold separately to similar customers in order to estimate standalone selling price.

Management is required to use judgment to develop its estimates of standalone selling price. Auditing the Company’s estimates of standalone selling price required a high degree of auditor judgment and an increased extent of effort, including the need to involve our data analytics specialists to assist in the testing of the standalone selling price analyses given the judgment required by management in this area.

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How the Critical Audit Matter Was Addressed in the Audit

Our audit procedures related to the testing of management’s estimation of standalone selling prices included the following, among others:

•We tested the effectiveness of controls over revenue, including those over the determination of estimated standalone selling price.

•We evaluated whether management’s significant accounting policies related to the estimation of standalone selling price were appropriate.

•With the assistance of our data analytics specialists, we evaluated the estimated standalone selling price analyses prepared by the Company, including testing the underlying detail of standalone sales and the mathematical accuracy of the calculations.

Goodwill – IP Optical Networks Reporting Unit — Refer to Notes 2 and 10 to the financial statements

Critical Audit Matter Description

The Company’s evaluation of goodwill for impairment involves the comparison of the fair value of each reporting unit to its carrying value. The Company used a combination of the income and market approaches to estimate reporting unit fair value. With respect to the income approach, management is required to make significant estimates and assumptions related to discount rates and forecasts of future revenue. Changes in these assumptions could have a significant impact on either the fair value, the amount of any goodwill impairment charge, or both. The goodwill balance was $417 million as of December 31, 2021, of which $192 million was allocated to the IP Optical Networks Reporting Unit (“IP Optical”). The carrying value of IP Optical exceeded its fair value as of December 31, 2021, and, therefore, $116 million of impairment was recognized.

Given the significant judgments made by management to estimate the fair value of IP Optical, performing audit procedures to evaluate the reasonableness of management’s estimates and assumptions related to the selection of the discount rate and forecasts of future revenue and profit margin required a high degree of auditor judgment and an increased extent of effort, including the need to involve our fair value specialists.

How the Critical Audit Matter Was Addressed in the Audit

Our audit procedures related to the discount rate and forecasts of future revenue and profit margin, used by management to estimate the fair value of IP Optical, included the following, among others:

•We tested the effectiveness of controls over management’s goodwill impairment evaluation, including those over the determination of the fair value of IP Optical, such as controls related to management’s selection of the discount rate and forecasts of future revenue and profit margin.

•We evaluated management’s ability to accurately forecast future revenues and profit margins by comparing actual results to management’s historical forecasts.

•We evaluated the reasonableness of management’s revenue and profit margin forecasts by comparing the forecasts to:

◦Historical revenues and profit margins.

◦Internal communications to management and the Board of Directors.

◦Forecasted information included in Company press releases as well as in analyst and industry reports for the Company and certain of its peer companies.

•We evaluated the impact of changes in management’s forecasts from the October 1, 2021, annual measurement date to December 31, 2021.

•With the assistance of our fair value specialists, we evaluated the reasonableness of the discount rate by:

◦Testing the source information underlying the determination of the discount rate and the mathematical accuracy of the calculation.

◦Developing a range of independent estimates and comparing those to the discount rate selected by management.

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/s/ Deloitte & Touche LLP

Dallas, Texas

March 11, 2022

We have served as the Company's auditor since 2005.

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RIBBON COMMUNICATIONS INC.

Consolidated Balance Sheets

(in thousands, except share and per share data)

Assets

Current assets:

Liabilities and Stockholders' Equity

Current liabilities:

Operating lease liabilities, net of current 55,196 72,614

Commitments and contingencies (Note 26)

Stockholders' equity:

Accumulated other comprehensive income (loss) 7,578 (4,942)

See notes to the consolidated financial statements.

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RIBBON COMMUNICATIONS INC.

Consolidated Statements of Operations

(in thousands, except per share data)

Year ended December 31,

Revenue:

Cost of revenue:

Operating expenses:

(Loss) earnings per share:

Shares used to compute (loss) earnings per share:

See notes to the consolidated financial statements.

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RIBBON COMMUNICATIONS INC.

Consolidated Statements of Comprehensive (Loss) Income

(in thousands)

Year ended December 31,

Other comprehensive income (loss), net of tax:

Foreign currency translation adjustments (239) 894 194

Employee retirement benefits — 2,585 (1,960)

Other comprehensive income (loss), net of tax 12,520 (7,469) (1,176)

See notes to the consolidated financial statements.

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RIBBON COMMUNICATIONS INC.

Consolidated Statements of Stockholders' Equity

(in thousands, except share data)

Common stock

Vesting of restricted stock awards and units 1,504,707 —

Vesting of performance-based stock awards and units 9,466 —

Vesting of restricted stock awards and units 2,246,690 1 1

Vesting of performance-based stock units 323,752 —

Vesting of restricted stock awards and units 3,653,552 —

Vesting of performance-based stock units 1,557,656 —

See notes to the consolidated financial statements.

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RIBBON COMMUNICATIONS INC.

Consolidated Statements of Cash Flows

(in thousands)

Year ended December 31,

Cash flows from operating activities:

Depreciation and amortization of property and equipment 16,962 17,188 11,949

Decrease (increase) in fair value of investments 71,252 (30,296) —

Reduction to deferred purchase consideration — (70) (8,124)

Changes in operating assets and liabilities:

Cash flows from investing activities:

Business acquisitions, net of cash acquired — (346,852) —

Proceeds from sale of business 2,944 — —

Sales/maturities of marketable securities — — 7,295

Proceeds from the sale of fixed assets — 43,500 —

Cash flows from financing activities:

Borrowings under revolving line of credit — 615 117,000

Principal payments on revolving line of credit — (8,615) (164,000)

Principal payment of debt, related party — — (24,716)

Payment of deferred purchase consideration — — (21,876)

Principal payments of finance leases (903) (1,258) (913)

Proceeds from the exercise of stock options 24 70 235

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RIBBON COMMUNICATIONS INC.

Consolidated Statements of Cash Flows (continued)

(in thousands)

Year ended December 31,

Repurchase of common stock — — (4,536)

Effect of exchange rate changes on cash and cash equivalents (523) 260 70

Net (decrease) increase in cash and cash equivalents (29,212) 91,054 949

Supplemental disclosure of cash flow information:

Supplemental disclosure of non-cash investing activities:

Capital expenditures incurred, but not yet paid $ 2,269 $ 3,749 $ 2,566

Property and equipment acquired under finance leases $ — $ — $ 1,442

Supplemental disclosure of non-cash financing activities:

See notes to the consolidated financial statements.

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Notes to Consolidated Financial Statements

(1) NATURE OF THE BUSINESS

Ribbon Communications Inc. ("Ribbon" or the "Company") is a leading global provider of communications technology to service providers and enterprises. The Company provides a broad range of software and high-performance hardware products, network solutions, and services that enable the secure delivery of data and voice communications, and high-bandwidth networking and connectivity for residential consumers and for small, medium, and large enterprises and industry verticals such as finance, education, government, utilities, and transportation. Ribbon's mission is to create a recognized global technology leader providing cloud-centric solutions that enable the secure exchange of information, with unparalleled scale, performance, and elasticity. The Company is headquartered in Plano, Texas, and has a global presence with research and development, or sales and support locations in over thirty-five countries around the world.

(2) BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Basis of Presentation

The consolidated financial statements have been prepared in United States dollars, in accordance with accounting principles generally accepted in the United States ("GAAP").

On December 1, 2020 (the "Kandy Sale Date"), American Virtual Cloud Technologies, Inc. ("AVCT") completed the purchase of the Company's cloud-based enterprise service business (the "Kandy Communications Business"). The revenue and expenses of the Kandy Communications Business are excluded from the Company's consolidated financial statements for the period subsequent to the Kandy Sale Date.

On March 3, 2020 (the "ECI Acquisition Date"), the Company merged with ECI Telecom Group Ltd ("ECI") (the "ECI Acquisition"). The financial results of ECI are included in the Company's consolidated financial statements for the period subsequent to the ECI Acquisition Date.

On February 28, 2019 (the "Anova Acquisition Date"), the Company acquired the business and technology assets of Anova Data, Inc. ("Anova"). The financial results of Anova are included in the Company's consolidated financial statements for the period subsequent to the Anova Acquisition Date.

Significant Accounting Policies

Principles of Consolidation

The accompanying consolidated financial statements include the accounts of Ribbon and its wholly-owned subsidiaries. All intercompany transactions and balances have been eliminated in consolidation.

Use of Estimates and Judgments

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting periods. Significant estimates and judgments relied upon in preparing these consolidated financial statements include accounting for business combinations, revenue recognition for multiple element arrangements, inventory valuations, assumptions used to determine the fair value of stock-based compensation, intangible assets, goodwill, debentures and warrants, legal contingencies and recoverability of Ribbon's net deferred tax assets and the related valuation allowances. Ribbon regularly assesses these estimates and records changes in estimates in the period in which they become known. Ribbon bases its estimates on historical experience and various other assumptions that it believes to be reasonable under the circumstances. Actual results could differ from those estimates.

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RIBBON COMMUNICATIONS INC.

Notes to Consolidated Financial Statements (Continued)

Reclassifications

In the fourth quarter of 2021, the Company reclassified amounts recorded for amortization of certain acquired intangible assets in prior presentations from Total operating expenses under the caption "Amortization of acquired intangible assets" to Cost of revenue under the caption "Amortization of acquired technology" in the consolidated statements of operations. The Company's management believes this presentation aids in the comparability of its financial statements to industry peers. These reclassifications did not impact operating income (loss), net income (loss) or earnings (loss) per share for any historical periods. These reclassifications also did not impact the consolidated balance sheets or statements of cash flows for any historical periods. The Company reports depreciation of property and equipment related to production activities as components of cost of revenue.These reclassifications for the years ended December 31, 2020 and 2019 were as follows (in thousands):

In addition, certain other reclassifications, not affecting previously reported net income (loss), have been made to the previously issued financial statements to conform to the current year presentation.

Business Combinations

The Company recognizes identifiable assets acquired and liabilities assumed at their acquisition date fair values. Goodwill as of the acquisition date is measured as the excess of consideration transferred over the net of the acquisition date fair values of the assets acquired and the liabilities assumed and represents the expected future economic benefits arising from other assets acquired in the business combination that are not individually identified and separately recognized. While the Company uses its best estimates and assumptions as part of the purchase price allocation process to accurately value assets acquired and liabilities assumed at the acquisition date, its estimates are inherently uncertain and subject to refinement. As a result, during the measurement period, which may be up to one year from the acquisition date, the Company records adjustments to the assets acquired and liabilities assumed with the corresponding offset to goodwill to the extent that it identifies adjustments to the preliminary purchase price allocation. Upon the conclusion of the measurement period or final determination of the values of assets acquired and liabilities assumed, whichever comes first, any subsequent adjustments are recorded to the consolidated statements of operations.

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RIBBON COMMUNICATIONS INC.

Notes to Consolidated Financial Statements (Continued)

Revenue Recognition

The Company derives revenue from two primary sources: products and services. Product revenue includes the Company's hardware and software that function together to deliver the products' essential functionality. Software and hardware are also sold on a standalone basis. Services include customer support (software updates, upgrades and technical support), consulting, design services, installation services and training. Generally, contracts with customers contain multiple performance obligations, consisting of products and services. For these contracts, the Company accounts for individual performance obligations separately if they are considered distinct.

When an arrangement contains more than one performance obligation, the Company will allocate the transaction price to each performance obligation on a relative standalone selling price basis. The Company utilizes the observable price of goods and services when they are sold separately to similar customers in order to estimate standalone selling price.

The Company's software licenses typically provide a perpetual right to use the Company's software. The Company also sells term-based software licenses that expire and Software-as-a-Service ("SaaS")-based software which are referred to as subscription arrangements. The Company does not customize its software nor are installation services required, as the customer has a right to utilize internal resources or a third-party service company. The software and hardware are delivered before related services are provided and are functional without professional services or customer support. The Company has concluded that its software licenses are functional intellectual property that are distinct, as the user can benefit from the software on its own. Product revenue is typically recognized upon transfer of control or when the software is made available for download, as this is the point the user of the software can direct the use of, and obtain substantially all of the remaining benefits from, the functional intellectual property. The Company begins to recognize software revenue related to the renewal of subscription software licenses at the start of the subscription period.

The Company offers warranties on its products. Certain of the Company's warranties are considered to be assurance-type in nature, ensuring the product is functioning as intended. Assurance-type warranties do not represent separate performance obligations. The Company also sells separately-priced maintenance service contracts which qualify as service-type warranties and represent separate performance obligations. The Company does not allow and has no history of accepting product returns.

Services revenue includes revenue from customer support and other professional services. Customer support includes software updates on a when-and-if-available basis, telephone support, integrated web-based support and bug fixes or patches. The Company sells its customer support contracts at a percentage of list or net product price. Customer support revenue is recognized ratably over the term of the customer support agreement, which is typically one year.

The Company's professional services include consulting, technical support, resident engineer services, design services and installation services. Because control transfers over time, revenue is recognized based on progress toward completion of the performance obligation. The method to measure progress toward completion requires judgment and is based on the nature of the products or services to be provided. The Company generally uses the input method to measure progress for its contracts because it believes such method best depicts the transfer of assets to the customer, which occurs as the Company incurs costs for the contracts. However, in some instances, the Company uses the output method because it best depicts the transfer of asset to the customer. Under the cost-to-cost measure of progress, the progress toward completion is measured based on the ratio of costs incurred to date to the total estimated costs at completion of the performance obligation. When the measure of progress is based upon expended labor, progress toward completion is measured as the ratio of labor time expended to date versus the total estimated labor time required to complete the performance obligation. Revenue is recorded proportionally as costs are incurred or as labor is expended. Costs to fulfill these obligations include internal labor as well as subcontractor costs.

Customer training includes courses offered by the Company. The related revenue is typically recognized as the training services are performed.

Operating Segments

The Company's chief operating decision maker (the "CODM") is its president and chief executive officer. Effective in the fourth quarter of 2020 and in connection with the ECI Acquisition, the CODM began to assess the Company's performance based on the performance of two separate organizations within Ribbon: the Cloud and Edge segment ("Cloud and Edge") and the IP Optical Networks segment ("IP Optical Networks"). Financial information for the IP Optical Networks segment is not

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presented for any years prior to 2020, as this segment arose from the ECI Acquisition, and accordingly is not included in the Company's consolidated financial statements for the year ended December 31, 2019.

Financial Instruments

The carrying amounts of Ribbon's financial instruments approximate their fair values and include accounts receivable, equity securities and convertible warrants received as sale consideration, borrowings under a revolving credit facility, accounts payable and term debt.

Financial instruments with remaining maturities or that are due within one year from the balance sheet date are classified as current. Financial instruments with maturities or that are payable more than one year from the balance sheet date are classified as noncurrent.

Fair Value Option - Investment in AVCT

The Company received debentures and warrants as sale consideration in connection with the sale of the Kandy Communications Business. On September 8, 2021 (the "Debenture Conversion Date"), the debentures were converted into 13,700,421 shares of AVCT common stock (the "Debenture Shares") (see Note 4 for a discussion of the valuation of the debentures, warrants and Debenture Shares). In connection with the conversion of the debentures to the Debenture Shares, the Company elected to use the fair value option to account for its equity investment in AVCT as permitted under Accounting Standards Codification ("ASC") 825, Financial Instruments ("ASC 825"), which then refers to ASC 820, Fair Value Measurement ("ASC 820") to provide the fair value framework for valuing such investments. In accordance with ASC 820, the Company is recording the investment in AVCT at fair value, with changes in fair value recorded as a component of Other (expense) income, net, in the consolidated statements of operations.

Restricted Cash

The Company classifies as restricted cash all cash pledged as collateral to secure long-term obligations and all cash whose use is otherwise limited by contractual provisions. At December 31, 2021, the Company had $2.6 million of restricted cash, representing restricted short-term bank deposits pledged to secure certain performance and financial bonds as security for the Company's obligations under tenders, contracts and to one of its main subcontractors.

At December 31, 2020, the Company had $7.3 million of restricted cash, comprised of $4.6 million restricted in connection with a tax payment on certain fixed assets formerly held by ECI that were sold in connection with the ECI Acquisition, and $2.7 million of restricted short-term bank deposits pledged to secure certain performance and financial bonds as security for the Company's obligations under tenders, contracts and to one of its main subcontractors.

Transfers of Financial Assets

The Company's IP Optical Networks segment maintains customer receivables factoring agreements with a number of financial institutions. Under the terms of these agreements, the Company may transfer receivables to the financial institutions, on a non-recourse basis, provided that the financial institutions approve the receivables in advance. The Company maintains credit insurance policies from major insurance providers or obtains letters of credit from the customers for a majority of its factored trade receivables. The Company accounts for the factoring of its financial assets as a sale of the assets and records the factoring fees, when incurred, as a component of interest expense in the consolidated statements of operations, and the proceeds from the sales of receivables are included in cash from operating activities in the consolidated statements of cash flows.

During the year ended December 31, 2021, the Company received $118.5 million of cash from the sale of certain accounts receivable and recorded $0.8 million of interest expense in connection with these transactions. During the year ended December 31, 2020, the Company received $119.8 million of cash from the sale of certain accounts receivable and recorded $0.9 million of interest expense in connection with these transactions.

Foreign Currency Translation

For foreign subsidiaries where the functional currency is the local currency, assets and liabilities are translated into U.S.

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dollars at the current exchange rate on the balance sheet date. Revenue and expenses are translated at average rates of exchange prevailing during each period. Translation adjustments for these subsidiaries are included in Accumulated other comprehensive income.

For foreign subsidiaries where the functional currency is the U.S. dollar, monetary assets and liabilities are translated into U.S. dollars at the current exchange rate on the balance sheet date. Nonmonetary assets and liabilities are remeasured into U.S. dollars at historical exchange rates. Revenue and expense items are translated at average rates of exchange prevailing during each period. Translation adjustments for these subsidiaries are included in Other expense (income), net.

Realized and unrealized foreign currency exchange gains and losses arising from transactions denominated in currencies other than the subsidiary's functional currency are reflected in earnings.

The Company records its foreign currency gains (losses) as a component of Other (expense) income, net. The Company recognized net foreign currency losses of $5.0 million, $3.0 million and $1.1 million for the years ended December 31, 2021, 2020 and 2019, respectively.

Inventory

Inventory is recorded at the lower of cost or market value using the first-in, first-out convention. The Company reduces the carrying value of inventory for those items that are potentially excess, obsolete or slow-moving based on changes in customer demand, technology developments or other economic factors.

Ribbon writes down evaluation equipment (equipment at customer sites for testing and evaluation) at the time of shipment to its customers, as it is probable that the inventory value will not be realized.

Deferred product costs represent deferred cost of revenue for product shipments to customers prior to satisfaction of Ribbon's revenue recognition criteria. The Company classifies inventory that is not expected to be consumed within one year from the balance sheet date as noncurrent and includes such inventory as a component of Other assets.

Property and Equipment

Property and equipment are stated at cost, net of accumulated depreciation. Expenditures for maintenance and repairs are charged to expense as incurred. Depreciation is computed using the straight-line method over the estimated useful lives of the related assets, which range from two to five years. Leasehold improvements are amortized over the lesser of the lease term or five years. When an asset is sold or retired, the cost and related accumulated depreciation or amortization are eliminated, and the resulting gain or loss, if any, is recognized in (Loss) income from operations in the consolidated statement of operations. The Company reviews property and equipment for impairment in the same manner as intangible assets discussed below.

Software development costs associated with internal use software are incurred in three stages of development: the preliminary project stage, the application development stage and the post-implementation stage. Costs incurred during the preliminary project and post-implementation stages are expensed as incurred. Certain qualifying costs incurred during the application development stage are capitalized as property and equipment. Internal use software is amortized on a straight-line basis over its estimated useful life of three years, beginning when the software is ready for its intended use.

Intangible Assets and Goodwill

The Company's intangible assets are comprised of in-process research and development, developed technology, customer relationships, trade names, and internal use software. Intangible assets are reviewed for impairment when events or changes in circumstances indicate that their carrying amounts may not be recoverable based upon the estimated undiscounted cash flows. Recoverability of intangible assets with estimated lives and other long-lived assets is measured by a comparison of the carrying amount of an asset or asset group to future net undiscounted cash flows expected to be generated by the asset or asset group. If these comparisons indicate that an asset is not recoverable, the Company will recognize an impairment loss for the amount by which the carrying value of the asset or asset group exceeds the related estimated fair value. Estimated fair value is based on either discounted future operating cash flows or appraised values, depending on the nature of the asset. The Company amortizes its intangible assets over their respective useful lives, with the exception of in-process research and development,

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which has an indefinite life until the product is generally available, at which time such asset is typically reclassified to developed technology, and the Company begins to amortize this asset. See Note 10 for additional information regarding the Company's intangible assets.

Goodwill is recorded when the consideration for an acquisition exceeds the fair value of net tangible and identifiable intangible assets acquired. Goodwill is not amortized, but instead is tested for impairment at least annually, or more frequently if indicators of potential impairment exist, by comparing the fair value of the Company's reporting unit to its carrying value.

Prior to 2020, the Company's annual test for impairment of goodwill was completed as of November 30. Effective in 2020, the Company changed its annual goodwill impairment test date from November 30 to October 1. This change did not have a material impact on the Company's consolidated financial statements.

As described above, effective in the fourth quarter of 2020, the Company determined that it has two operating segments: Cloud and Edge, and IP Optical Networks. For the purpose of testing goodwill for impairment, all goodwill is assigned to a reporting unit, which may be either an operating segment or a portion of an operating segment. The Company's reporting units are its operating segments. The Company performs a fair value analysis using both an income and market approach, which encompasses a discounted cash flow analysis and a guideline public company analysis using selected multiples. The Company assesses each valuation methodology based upon the relevance and availability of the data at the time the valuation is performed and the methodologies are weighted appropriately. Any impairment charges are reported separately in the Company's consolidated statements of operations.

Stock-Based Compensation

The Company's stock-based compensation cost is measured at the grant date based on the fair value of the award and is recognized as expense over the requisite service period, which generally represents the vesting period, and includes an estimate of the awards that will be forfeited.

The Company uses the Black-Scholes valuation model for estimating the fair value on the date of grant of stock options. The fair value of stock option awards is affected by the Company's stock price as well as valuation assumptions, including the volatility of Ribbon's stock price, expected term of the option, risk-free interest rate and expected dividends.

The Company may grant to certain of its executives performance-based stock units ("PSUs") that include a market condition. The Company uses a Monte Carlo simulation approach to model future stock price movements based upon the risk-free rate of return, the volatility of each entity and the pair-wise covariance between each entity. These results are then used to calculate the grant date fair values of the PSUs.

Concentration of Risk

The financial instruments that potentially subject Ribbon to concentrations of credit risk are cash, restricted cash and accounts receivable. The Company's cash equivalents and investments were managed by one financial institution at December 31, 2021. Historically, the Company has not experienced significant losses due to such bank depository concentration. The Company's investments at December 31, 2021 and 2020 consisted of securities of AVCT (see Note 4).

Certain components and software licenses from third parties used in Ribbon's products are procured from single sources of supply. The failure of a supplier, including a subcontractor, to deliver on schedule could delay or interrupt Ribbon's delivery of products and thereby materially adversely affect Ribbon's revenue and operating results.

Advertising Costs

Advertising costs are expensed as incurred and included as a component of Sales and marketing expense in the Company's consolidated statements of operations. Advertising expenses were $1.6 million for the year ended December 31, 2021, $0.8 million for the year ended December 31, 2020 and $0.5 million for the year ended December 31, 2019.

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Loss Contingencies and Reserves

Ribbon is subject to ongoing business risks arising in the ordinary course of business, including legal claims, that affect the estimation process of the carrying value of assets, the recording of liabilities and the possibility of various loss contingencies. An estimated loss contingency is accrued when it is probable that a liability has been incurred or an asset has been impaired and the amount of loss can be reasonably estimated. Ribbon regularly evaluates current information available to determine whether such amounts should be adjusted and records changes in estimates in the period they become known.

An allowance for doubtful accounts is estimated based on the Company's assessment of the collectability of specific customer accounts.

Ribbon accrues for royalties for technology that it licenses from vendors based on established royalty rates and usage. Ribbon is periodically contacted by third parties who claim that Ribbon's products infringe on certain intellectual property of a third party. Ribbon evaluates these claims and accrues amounts when it is probable that the obligation has been incurred and the amounts are reasonably estimable.

Warranty

The Company records warranty liabilities for estimated costs of fulfilling its obligations under standard limited hardware and software warranties at the time of sale. The specific warranty terms and conditions vary depending upon the country in which the Company does business, but generally includes material costs, technical support, labor and associated overhead over a period ranging from one to three years. The Company assumed ECI's warranty liability in connection with the ECI Acquisition. At December 31, 2021, the Company's liability for product warranties was $13.1 million, of which $5.9 million was current and included in Accrued expenses and other and $7.2 million was long-term and included in Other long-term liabilities in the Company's consolidated balance sheet. At December 31, 2020, the Company's liability for product warranties was $14.9 million, of which $6.5 million was current and included in Accrued expenses and other, and $8.4 million was long-term and included in Other long-term liabilities in the Company's consolidated balance sheet.

Research and Development Grants

The Company records grants received from the Office of the Innovation Authority of the Israeli Ministry of Economics (the "IIA") as a reduction to Research and development expense. Royalties payable to the IIA are recognized pursuant to sales of related products and are included in Cost of revenue - product (see Note 26).

Accounting for Leases

The Company accounts for its leases in accordance with Accounting Standards Codification ("ASC") 842, Leases ("ASC 842") (see Note 21). The Company has operating and finance leases for corporate offices, research and development facilities, and certain equipment. Operating leases are reported separately in the Company's consolidated balance sheets at December 31, 2021 and 2020. Assets acquired under finance leases are included in Property and equipment, net, in the consolidated balance sheets at December 31, 2021 and 2020.

The Company determines if an arrangement is a lease at inception. A contract is determined to contain a lease component if the arrangement provides the Company with a right to control the use of an identified asset. Lease agreements may include lease and non-lease components. In such instances for all classes of underlying assets, the Company does not separate lease and non-lease components but rather, accounts for the entire arrangement under leasing guidance. Leases with an initial term of 12 months or less are not recorded on the balance sheet and lease expense for these leases is recognized on a straight-line basis over the lease term.

For operating leases, lease expense for minimum fixed lease payments is recognized on a straight-line basis over the lease term. The expense for finance leases includes both interest and amortization expense components, with the interest component calculated based on the effective interest method and the amortization component calculated based on straight-line amortization of the right-of-use asset over the lease term. Lease contracts may contain variable lease costs, such as common area maintenance, utilities and tax reimbursements that vary over the term of the contract. Variable lease costs are not included in minimum fixed lease payments and as a result, are excluded from the measurement of the right-of-use assets and lease

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liabilities. The Company expenses all variable lease costs as incurred.

Accounting for Income Taxes

Deferred tax assets and liabilities are recognized for the expected future consequences of events that have been reflected in the consolidated financial statements. Deferred tax assets and liabilities are determined based on the differences between the financial reporting and tax basis of assets and liabilities and operating loss carryforwards, using tax rates expected to be in effect for the years in which the differences are expected to reverse. The Company records valuation allowances to reduce deferred income tax assets to the amount that is more likely than not to be realized.

The Company has provided for income taxes on the undistributed earnings of its non-U.S. subsidiaries as of December 31, 2021, excluding Ireland and Israel. These subsidiaries, excluding Ireland and Israel, are cost-plus or limited risk distributors that are not anticipated to need to use excess funds locally. Accordingly, the Company is required to recognize and record deferred taxes in 2021. The deferred taxes are recorded on the entire outside basis differences related to the foreign subsidiaries, the largest of these differences being undistributed earnings.

The Company determines whether it is more likely than not that a tax position will be sustained upon examination. If it is not more likely than not that a position will be sustained, no amount of the benefit attributable to the position is recognized. The tax benefit to be recognized of any tax position that meets the more likely than not recognition threshold is calculated as the largest amount that is more than 50% likely of being realized upon resolution of the contingency. The Company accounts for interest and penalties related to uncertain tax positions as part of its provision for income taxes.

Defined Benefit Plans

The Company has defined benefit plans for some of its employees at various international locations. The Company recognizes retirement benefit assets or liabilities in the consolidated balance sheets reflecting the funded status of pension and other retirement benefit plans. Retirement benefit assets and liabilities are adjusted for the difference between the benefit obligations and the plan assets at fair value (measured at year-end), with the offset recorded directly to stockholders' equity through accumulated other comprehensive income (loss), net of tax. The amount recorded in stockholders' equity represents the after-tax unamortized actuarial gains or losses, unamortized transition obligations and unamortized prior service costs.

Recent Accounting Pronouncements

In December 2019, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes ("ASU 2019-12"), which modifies Accounting Standards Codification ("ASC") 740, Income Taxes (Topic 740), to simplify the accounting for income taxes. ASU 2019-12 addresses the accounting for hybrid tax regimes, tax basis step-up in goodwill obtained in a transaction that is not a business combination, separate financial statements of legal entities not subject to tax, intraperiod tax allocation exception to incremental approach, ownership changes in investments - changes from a subsidiary to an equity method investment, ownership changes in investments - changes from an equity method investment to a subsidiary, interim period accounting for enacted changes in tax law and year-to-date loss limitation in interim period tax accounting. The adoption of ASU 2019-12 did not have a material impact on the Company's consolidated financial statements upon adoption.

In October 2021, the FASB issued ASU 2021-08, Business Combinations (Topic 805): Accounting for Contract Assets and Contract Liabilities from Contracts with Customers ("ASU 2021-08"), which amends ASC 805, Business Combinations (Topic 805), to add contract assets and contract liabilities to the list of exceptions to the recognition and measurement principles that apply to business combinations and to require that an acquiring entity recognize and measure contract assets and contract liabilities acquired in a business combination in accordance with ASC 606, Revenue from Contracts with Customers (Topic 606) ("ASC 606"). Under current GAAP, an acquirer generally recognizes such items at fair value on the acquisition date. While primarily related to contract assets and contract liabilities that were accounted for by the acquiree in accordance with ASC 606, ASU 2021-08 also applies to contract assets and contract liabilities from other contracts to which the provisions of ASC 606 apply, such as contract liabilities from the sale of nonfinancial assets within the scope of ASU 2017-05, Other Income - Gains and Losses from the Derecognition of Nonfinancial Assets (Subtopic 610-20). ASU 2021-08 is effective for the Company January 1, 2023, with early adoption permitted. The Company believes that the adoption of ASU 2021-08 could have

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a material impact on its consolidated financial statements for periods including and subsequent to significant business acquisitions.

In January 2021 the FASB issued ASU 2021-01, Reference Rate Reform (Topic 848): Scope ("ASU 2021-01"), which refines the scope of ASC 848, Reference Rate Reform, and clarifies some of its guidance as part of the FASB's monitoring of global reference rate reform activities. ASU 2021-01 permits entities to elect certain optional expedients and exceptions when accounting for derivative contracts and certain hedging relationships affected by changes in the interest rates used for discounting cash flows, for computing variation margin settlements, and for calculating price alignment interest in connection with reference rate reform activities under way in global financial markets (the "discounting transition"). ASU 2021-01 is effective for the Company prospectively in any period through December 31, 2022 that a modification is made to the terms of the derivatives affected by the discounting transition. The Company does not believe the adoption of ASU 2021-01 will have a material impact on its consolidated financial statements.

(3) BUSINESS ACQUISITIONS

ECI

On the ECI Acquisition Date, Ribbon completed its merger transaction with ECI in accordance with the terms of the Agreement and Plan of Merger, dated as of November 14, 2019, by and among Ribbon, ECI, an indirect wholly-owned subsidiary of Ribbon ("Merger Sub"), Ribbon Communications Israel Ltd. and ECI Holding (Hungary) Kft pursuant to which Merger Sub merged with and into ECI, with ECI surviving such merger as a wholly-owned subsidiary of Ribbon. Prior to the ECI Acquisition Date, ECI was a privately-held global provider of end-to-end packet optical transport and software-defined networking ("SDN") and network function virtualization ("NFV") solutions for service providers, enterprises and data center operators.

As consideration for ECI, Ribbon issued the ECI shareholders and certain others 32.5 million shares of Ribbon common stock with a fair value of $108.6 million (the "Stock Consideration") and paid $322.5 million of cash (the "Cash Consideration"), comprised of $183.3 million to repay ECI's outstanding debt, including both principal and interest, and $139.2 million paid to ECI's selling shareholders. In addition, ECI shareholders received $33.4 million from the sale of certain of ECI's real estate assets. Cash Consideration was financed through cash on hand and committed debt financing consisting of a new $400 million term loan facility and $100 million revolving credit facility, which was undrawn at the ECI Acquisition Date.

The ECI Acquisition has been accounted for as a business combination and the financial results of ECI have been included in the Company's consolidated financial statements for the period subsequent to the ECI Acquisition. The Company's financial results for the year ended December 31, 2020 included $260.5 million of revenue and $52.9 million of net loss attributable to ECI.