RAMBUS INC 10-K

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations This report contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934 as described in more detail under “Note Regarding Forward-Looking Statements.” Our forward-looking statements are based on current expectations, forecasts and assumptions and are subject to risks, uncertainties and changes in condition, significance, value and effect. As a result of the factors described herein, and in the documents incorporated herein by reference, including, in particular, those factors described under “Risk Factors,” we undertake no obligation to publicly disclose any revisions to these forward-looking statements to reflect events or circumstances occurring subsequent to filing this report with the Securities and Exchange Commission. The following discussion and analysis should be read in conjunction with the consolidated financial statements and related notes that are included elsewhere in this report. Executive Summary Highlights from our annual results were as follows: • Revenue of $242.7 million; • Operating expenses of $228.8 million; • GAAP diluted net loss per share of $0.39; • Net cash provided by operating activities of $185.5 million We had record annual product revenue of $114.0 million in 2020, which was primarily driven by our memory interface chips, and was up 56% as compared to 2019. In addition, our cash provided by operating activities for 2020 was up 44% as compared to 2019. 29 Tab le of Contents Business Overview Rambus produces products and innovations that address the fundamental challenges of accelerating data. We make industry-leading chips and IP that enable critical performance improvements for data center and other growing markets. The ongoing shift to the cloud, along with the widespread advancement of AI across the data center, 5G, automotive and IoT, has led to exponential growth in data usage and tremendous demands on data infrastructure. Creating fast and safe connections, both in and across systems, remains one of the most mission-critical design challenges limiting performance in advanced hardware for these markets. As an industry pioneer with over 30 years of advanced semiconductor design experience, Rambus is ideally positioned to address the challenges of moving and protecting data. We are a leader in high-performance memory subsystems, providing chips, IP and innovations that maximize the performance and security in data-intensive systems. Whether in the cloud, at the edge or in your hand, real-time and immersive applications depend on data throughput and integrity. Rambus products and innovations deliver the increased bandwidth, capacity and security required to meet the world’s data needs and drive ever-greater end-user experiences. Our strategic objectives are focusing our product portfolio and research around our core strength in semiconductors, optimizing our operational efficiency, and leveraging our strong cash generation to re-invest for growth. We continue to maximize synergies across our businesses and customer base, leveraging the significant overlap in our ecosystem of customers, partners and influencers. The Rambus product and technology roadmap, as well as our go-to-market strategy, is driven by the application-specific requirements of our focus markets. Revenue Sources Our patented inventions are offered to our customers through patent, technology, software and IP core licenses, as well as memory interface chips. Today, a significant source of revenue is derived from our Architecture Licenses, through which we provide our customers a license to use a certain portion of our broad worldwide portfolio of patented inventions. Our Architecture Licenses enable our customers to use the licensed portion of our portfolio of patented inventions in the customer’s own digital electronics products, systems or services. The licenses may also define the specific field of use where our customers may use or employ our inventions in their products. License agreements are structured with fixed or variable or a hybrid of fixed and variable royalty payments over certain defined periods ranging for periods of up to ten years. Leading semiconductor and electronic system companies such as AMD, Broadcom, Cisco, Fujitsu, IBM, Marvell, Mediatek, Micron, Nanya, NVIDIA, Panasonic, Phison, Qualcomm, Renesas, Samsung, SK hynix, Socionext, STMicroelectronics, Toshiba, Western Digital, Winbond, and Xilinx have licensed our patents. The vast majority of our patents were secured through our internal research and development efforts. We also offer our customers technology licenses to support the implementation and adoption of our technology in their products or services. Our customers include leading companies such as IBM, Panasonic, Qualcomm, Samsung, Sony and Toshiba. Our technology license offerings include a range of technologies for incorporation into our customers’ products and systems. We also offer a range of services as part of our technology licenses which can include know-how and technology transfer, product design and development, system integration, and other services. These technology license agreements may have both a fixed price (non-recurring) component and ongoing use fees and in some cases, royalties. Further, under technology licenses, our customers typically receive licenses to our patents necessary to implement these solutions in their products with specific rights and restrictions to the applicable patents elaborated in their individual contracts with us. Revenues from royalties accounted for 33%, 41% and 56% of our consolidated revenue for the years ended December 31, 2020, 2019 and 2018, respectively. The remainder of our revenue is product revenue, contract and other revenue, which includes our product sales, IP core licenses, software licenses and related implementation, support and maintenance fees, and engineering services fees. The timing and amounts invoiced to customers can vary significantly depending on specific contract terms and can therefore have a significant impact on deferred revenue or accounts receivable in any given period. Product revenue accounted for 47%, 33% and 17% of our consolidated revenue for the years ended December 31, 2020, 2019 and 2018, respectively. Contract and other revenue accounted for 20%, 27% and 27% of our consolidated revenue for the years ended December 31, 2020, 2019 and 2018, respectively. Costs and Expenses Cost of product revenue for 2020 increased approximately $10.5 million to $37.7 million from $27.2 million as compared to 2019 primarily due to increased cost of sales associated with our memory interface chips. 30 Tab le of Contents Cost of contract and other revenue for 2020 decreased approximately $4.3 million to $5.6 million from $9.9 million as compared to 2019 primarily due to incurring lower costs as a result of the divestiture of our former Payments and Ticketing businesses in the fourth quarter of 2019. Research and development expenses continue to play a key role in our efforts to maintain product innovations. Our research and development expenses for 2020 decreased $17.0 million as compared to 2019 primarily due to decreased headcount-related expenses of $11.8 million (which includes the reduction in headcount due to the divestiture of the Payments and Ticketing businesses in 2019), consulting costs of $5.2 million, travel costs of $1.9 million and stock-based compensation expense of $1.0 million, offset by increased retention bonus expense related to acquisitions of $2.0 million and prototyping costs of $0.9 million. Sales, general and administrative expenses for 2020 decreased $15.8 million as compared to 2019 primarily due to decreased headcount-related expenses of $5.4 million, acquisition and divestiture-related costs of $4.1 million, travel costs of $3.4 million, consulting costs of $2.7 million and depreciation expense of $1.2 million, offset by increased bonus accrual expense of $0.5 million and stock-based compensation expense of $0.3 million. Impact of the COVID-19 Pandemic In December 2019, the Novel Coronavirus (COVID-19) was reported in China, in January 2020 the World Health Organization (“WHO”) declared it a Public Health Emergency of International Concern, and in March 2020 the WHO declared it a pandemic. The COVID-19 pandemic has created significant global economic uncertainty and may adversely impact the business of our customers, partners and vendors. The extent of the impact of the Novel Coronavirus (COVID-19) on our operational and financial performance will depend on certain developments, including the duration and spread of the outbreak, impact on our customers and our sales cycles, and impact on our partners or employees, all of which are uncertain and cannot be predicted. At this point, the extent to which the Novel Coronavirus (COVID-19) may impact our financial condition or results of operations remains uncertain. Actual results could differ from any estimates and any such differences could be material to our financial statements. Furthermore, the effect of the Novel Coronavirus (COVID-19) may not be fully reflected in our results of operations until future periods, if at all. Trends There are a number of trends that may have a material impact on us in the future, including but not limited to, the evolution of memory and SerDes technology, adoption of security solutions, the use and adoption of our inventions or technologies generally, industry consolidation, and global economic conditions with the resulting impact on sales of consumer electronic systems. We have a high degree of revenue concentration. Our top five customers for each reporting period represented approximately 46% of our revenue for 2020 as compared to 46% in 2019 and 49% in 2018. The particular customers which account for revenue concentration have varied from period-to-period as a result of the addition of new contracts, expiration of existing contracts, renewals of existing contracts, industry consolidation, and the volumes and prices at which the customers have recently sold to their customers. These variations are expected to continue in the foreseeable future. Our revenue from companies headquartered outside of the United States accounted for approximately 43% in 2020 as compared to 40% in 2019 and 44% in 2018. We expect that revenue derived from international customers will continue to represent a significant portion of our total revenue in the future. Currently, our revenue from international customers is denominated in U.S. dollars. For additional information concerning international revenue, refer to Note 7, “Segments and Major Customers,” of Notes to Consolidated Financial Statements of this Form 10-K. The royalties we receive from our semiconductor customers are partly a function of the adoption of our technologies by system companies. Many system companies purchase semiconductors containing our technologies from our customers and do not have a direct contractual relationship with us. Our customers generally do not provide us with details as to the identity or volume of licensed semiconductors purchased by particular system companies. As a result, we face difficulty in analyzing the extent to which our future revenue will be dependent upon particular system companies. As a part of our overall business strategy, from time to time, we evaluate businesses and technologies for potential acquisition that are aligned with our core business and designed to supplement our growth, including the 2019 acquisitions of Northwest Logic and the Secure Silicon IP and Protocols business from Verimatrix, formerly Inside Secure. Similarly, we evaluate our current businesses and technologies that are not aligned with our core business for potential divestiture, such as the sale of our Payments and Ticketing businesses to Visa International Service Association in 2019. We expect to continue to evaluate and potentially enter into strategic acquisitions or divestitures which may adversely impact our business and operating results. 31 Tab le of Contents Results of Operations The following table sets forth, for the periods indicated, the percentage of total revenue represented by certain items reflected in our consolidated statements of operations: Years Ended December 31, 2020 2019 2018 Revenue: Royalties 33.3 % 40.5 % 56.4 % Product revenue 47.0 % 32.6 % 16.7 % Contract and other revenue 19.7 % 26.9 % 26.9 % Total revenue 100.0 % 100.0 % 100.0 % Cost of revenue: Cost of product revenue 15.6 % 12.1 % 7.9 % Cost of contract and other revenue 2.3 % 4.4 % 5.1 % Amortization of acquired intangible assets 7.1 % 6.4 % 10.2 % Total cost of revenue 25.0 % 22.9 % 23.2 % Gross profit 75.0 % 77.1 % 76.8 % Operating expenses: Research and development 57.6 % 70.0 % 68.5 % Sales, general and administrative 35.3 % 45.3 % 42.5 % Amortization of acquired intangible assets 0.4 % 1.2 % 2.4 % Restructuring and other charges 1.7 % 3.9 % 1.0 % Loss on divestiture — % 3.3 % — % Change in fair value of earn-out liability (0.7) % — % — % Total operating expenses 94.3 % 123.7 % 114.4 % Operating loss (19.3) % (46.6) % (37.6) % Interest income and other income (expense), net 7.2 % 12.2 % 14.1 % Interest expense (4.2) % (4.4) % (7.0) % Interest and other income (expense), net 3.0 % 7.8 % 7.1 % Loss before income taxes (16.3) % (38.8) % (30.5) % Provision for income taxes 1.7 % 1.5 % 37.8 % Net loss (18.0) % (40.3) % (68.3) % Years Ended December 31, 2019 to 2020 2018 to 2019 (Dollars in millions) 2020 2019 2018 Change Change Total Revenue Royalties $ 81.0 $ 90.8 $ 130.5 (10.8) % (30.4) % Product revenue 114.0 73.0 38.7 56.2 % 88.6 % Contract and other revenue 47.7 60.2 62.0 (20.7) % (2.9) % Total revenue $ 242.7 $ 224.0 $ 231.2 8.4 % (3.1) % Royalty revenue Royalty revenue, which includes patent and technology license royalties, decreased approximately $9.8 million to $81.0 million for the year ended December 31, 2020 from $90.8 million for 2019. The decrease was due primarily to the timing of renewals and the related structure of architecture license agreements which include both fixed and variable components. 32 Tab le of Contents Royalty revenue decreased approximately $39.7 million to $90.8 million for the year ended December 31, 2019 from $130.5 million for 2018. The decrease was due primarily to the timing of renewals and the related structure of architecture license agreements which include both fixed and variable components. We are continuously in negotiations for licenses with prospective customers. We expect patent royalties will continue to vary from period to period based on our success in adding new customers, renewing or extending existing agreements, as well as the level of variation in our customers’ reported shipment volumes, sales price and mix, offset in part by the proportion of customer payments that are fixed or hybrid in nature. We also expect that our technology royalties will continue to vary from period to period based on our customers’ shipment volumes, sales prices, and product mix. Product revenue Product revenue consists of revenue from the sale of memory and security products. Product revenue increased approximately $41.0 million to $114.0 million for the year ended December 31, 2020 from $73.0 million for 2019. The increase was due to market share gains of our memory interface chips. Product revenue increased approximately $34.3 million to $73.0 million for the year ended December 31, 2019 from $38.7 million for 2018. The increase was primarily due to greater market share gains of our memory interface chips. We believe that product revenue will continue to increase in 2021 as compared to 2020, mainly from the sale of our memory interface chips. Our ability to continue to grow product revenue is dependent on, among other things, our ability to continue to obtain orders from customers and our ability to meet our customers’ demands. Contract and other revenue Contract and other revenue consists of revenue from technology development projects. Contract and other revenue decreased approximately $12.5 million to $47.7 million for the year ended December 31, 2020 from $60.2 million for 2019. The decrease was primarily due to the divestiture of our former Payments and Ticketing businesses resulting in no corresponding revenue in 2020, offset by growth experienced in our Silicon IP offerings. Contract and other revenue decreased approximately $1.8 million to $60.2 million for the year ended December 31, 2019 from $62.0 million for 2018. The decrease was primarily due to lower revenue associated with our Payments and Ticketing businesses, which were divested in the fourth quarter of 2019, offset by growth experienced in our Silicon IP offerings. We believe that contract and other revenue will fluctuate over time based on our ongoing technology development contractual requirements, the amount of work performed, the timing of completing engineering deliverables, and the changes to work required, as well as new technology development contracts booked in the future. Cost of product revenue Years Ended December 31, 2019 to 2020 2018 to 2019 (Dollars in millions) 2020 2019 2018 Change Change Cost of product revenue $ 37.7 $ 27.2 $ 18.3 39.0 % 48.4 % Cost of product revenue are costs attributable to the sale of memory and security products. Cost of product revenue also included costs attributable to the sale of lighting products in 2018. For the year ended December 31, 2020 as compared to 2019, cost of product revenue increased 39.0% primarily due to increased cost of sales associated with higher sales of memory interface chips. For the year ended December 31, 2019 as compared to 2018, cost of product revenue increased 48.4% primarily due to increased cost of sales associated with higher sales of memory products. In the near term, we expect costs of product revenue to be higher as we expect higher sales of our various products in 2021 as compared to 2020. 33 Table of Contents Cost of contract and other revenue Years Ended December 31, 2019 to 2020 2018 to 2019 (Dollars in millions) 2020 2019 2018 Change Change Cost of contract and other revenue $ 5.6 $ 9.9 $ 11.7 (43.0) % (15.4) % Cost of contract and other revenue reflects the portion of the total engineering costs which are specifically devoted to individual customer development and support services. For the year ended December 31, 2020 as compared to 2019, cost of contract and other revenue decreased 43.0% primarily due to the divestiture of our Payments and Ticketing businesses in the fourth quarter of 2019. For the year ended December 31, 2019 as compared to 2018, cost of contract and other revenue decreased 15.4% primarily due to lower revenue associated with our former Payments and Ticketing businesses, which were divested in the fourth quarter of 2019. In the near term, we expect cost of contract and other revenue to vary from period to period based on varying revenue recognized from contract and other revenue. Research and development expenses Years Ended December 31, 2019 to 2020 2018 to 2019 (Dollars in millions) 2020 2019 2018 Change Change Research and development expenses Research and development expenses $ 129.8 $ 145.8 $ 145.7 (11.0) % 0.0 % Stock-based compensation 10.0 11.0 12.6 (9.1) % (12.3) % Total research and development expenses $ 139.8 $ 156.8 $ 158.3 (10.8) % (1.0) % Research and development expenses are those expenses incurred for the development of applicable technologies. For the year ended December 31, 2020 as compared to 2019, total research and development expenses decreased 10.8% primarily due to decreased headcount-related expenses of $11.8 million (which includes the reduction in headcount due to the divestiture of the Payments and Ticketing businesses in 2019), consulting costs of $5.2 million, travel costs of $1.9 million and stock-based compensation expense of $1.0 million, offset by increased retention bonus expense related to acquisitions of $2.0 million and prototyping costs of $0.9 million. For the year ended December 31, 2019 as compared to 2018, total research and development expenses decreased 1.0% primarily due to decreased headcount-related expenses of $3.9 million, allocated information technology costs of $1.6 million and stock-based compensation expense of $1.5 million, offset by increased facilities costs of $2.1 million as discussed below, retention bonus accrual related to acquisitions of $2.0 million and engineering development tool costs of $1.2 million. On January 1, 2019, we adopted the New Leasing Standard using the alternative transition method. In accordance with the New Leasing Standard, we were required to derecognize our previous Sunnyvale and Ohio facilities as imputed facility obligations (as accounted for under the previous leasing guidance) and recognize these facilities as operating leases. This change resulted in no longer recognizing interest expense associated with these imputed facility lease obligations, but instead, recognizing lease expense that was included in operating costs and expenses. In the near term, we expect research and development expenses to be higher as we continue to make investments in the infrastructure and technologies required to maintain our product innovation in semiconductor, security and other technologies. 34 Table of Contents Sales, general and administrative costs Years Ended December 31, 2019 to 2020 2018 to 2019 (Dollars in millions) 2020 2019 2018 Change Change Sales, general and administrative costs Sales, general and administrative costs $ 69.9 $ 86.0 $ 89.1 (18.7) % (3.6) % Stock-based compensation 15.7 15.4 9.1 2.0 % 68.8 % Total sales, general and administrative costs $ 85.6 $ 101.4 $ 98.2 (15.5) % 3.2 % Sales, general and administrative expenses include expenses and costs associated with trade shows, public relations, advertising, litigation, general legal, insurance and other sales, marketing and administrative efforts. Consistent with our business model, our licensing, sales and marketing activities aim to develop or strengthen relationships with potential new and current customers. In addition, we work with current customers through marketing, sales and technical efforts to drive adoption of their products that use our innovations and solutions, by system companies. Due to the long business development cycles we face and the semi-fixed nature of sales, general and administrative expenses in a given period, these expenses generally do not correlate to the level of revenue in that period or in recent or future periods. For the year ended December 31, 2020 as compared to 2019, total sales, general and administrative costs decreased 15.5% primarily due to decreased headcount-related expenses of $5.4 million, acquisition and divestiture-related costs of $4.1 million, travel costs of $3.4 million, consulting costs of $2.7 million and depreciation expense of $1.2 million, offset by increased bonus accrual expense of $0.5 million and stock-based compensation expense of $0.3 million. For the year ended December 31, 2019 as compared to 2018, total sales, general and administrative costs increased 3.2% primarily due to increased stock-based compensation expense of $6.3 million primarily due to the termination of the former chief executive officer at the end of June 2018, acquisition and divestiture related costs of $5.2 million and facilities costs of $2.6 million (primarily due to the adoption of the New Leasing Standard beginning in 2019 as discussed above), offset by decreased headcount related expenses of $3.8 million, depreciation expense of $1.8 million, sales and marketing costs of $1.2 million, travel expenses of $1.2 million, consulting costs of $1.0 million, bonus accrual expense of $1.0 million and recruiting costs of $0.6 million. In the future, sales, general and administrative expenses will vary from period to period based on the trade shows, advertising, legal, acquisition and other sales, marketing and administrative activities undertaken, and the change in sales, marketing and administrative headcount in any given period. In the near term, we expect our sales, general and administrative expenses to remain relatively flat. Amortization of acquired intangible assets Years Ended December 31, 2019 to 2020 2018 to 2019 (Dollars in millions) 2020 2019 2018 Change Change Amortization of acquired intangible assets Amortization of acquired intangible assets included in total cost of revenue $ 17.4 $ 14.3 $ 23.7 21.2 % (39.6) % Amortization of acquired intangible assets included in total operating expenses 1.0 2.7 5.7 (61.3) % (51.5) % Total amortization of acquired intangible assets $ 18.4 $ 17.0 $ 29.4 7.9 % (41.9) % Amortization expense is related to various acquired IP. For the year ended December 31, 2020 as compared to 2019, total amortization of acquired intangible assets increased 7.9% primarily due to additional amortization from intangible assets acquired as part of the acquisitions from the second half of 2019, partially offset by certain other intangible assets being fully amortized. For the year ended December 31, 2019 as compared to 2018, total amortization of acquired intangible assets decreased 41.9% primarily due to certain intangible assets being fully amortized. 35 Table of Contents Restructuring and other charges Years Ended December 31, 2019 to 2020 2018 to 2019 (Dollars in millions) 2020 2019 2018 Change Change Restructuring and other charges $ 4.1 $ 8.8 $ 2.2 (53.6) % NM* _____________________________________ * NM — percentage is not meaningful In November 2020, we initiated a restructuring program to reduce overall expenses which is expected to improve future profitability by reducing spending on research and development efforts and sales, general and administrative programs. As a result, we recorded a charge of $3.3 million primarily related to headcount costs. During 2019, we initiated a restructuring program to reduce overall expenses. Additionally, we recorded other severance-related charges of $1.4 million. During 2018, we closed our lighting division and manufacturing operations in Brecksville, Ohio. As a result, we recorded a charge of $2.2 million related to employee terminations and severance costs, and facility-related costs. Refer to Note 18, “Restructuring and Other Charges,” of Notes to Consolidated Financial Statements of this Form 10-K for further discussion. Loss on divestiture Years Ended December 31, 2019 to 2020 2018 to 2019 (Dollars in millions) 2020 2019 2018 Change Change Loss on divestiture $ — $ 7.4 $ — — % 100.0 % During 2020 and 2018, we did not record a charge for loss on divestiture. During 2019, we entered into a share purchase agreement with Visa International Service Association (the “Purchaser”), pursuant to which the Purchaser had agreed to acquire all of the outstanding shares of our subsidiary, Smart Card Software Limited, which was comprised of our Payments and Ticketing businesses. The decision to sell these businesses reflected our review of our business to focus on products and offerings that are core to our semiconductor business. Consequently, we measured these businesses at the lower of their carrying value or fair value less any costs to sell, and subsequently recognized a loss of approximately $7.4 million during the year ended December 31, 2019. Refer to Note 17, “Divestiture,” of Notes to Consolidated Financial Statements of this Form 10-K for further discussion. Change in fair value of earn-out liability Years Ended December 31, 2019 to 2020 2018 to 2019 (Dollars in millions) 2020 2019 2018 Change Change Change in fair value of earn-out liability $ (1.8) $ — $ — 100.0 % — % During 2020, we recorded a full reduction in the fair value of the earn-out liability related to the 2019 asset purchase agreement to acquire the Secure Silicon IP and Protocols business from Verimatrix, formerly Inside Secure, since the specified performance milestones were not met for calendar year 2020, which resulted in a gain in our consolidated statements of operations. Interest and other income (expense), net Years Ended December 31, 2019 to 2020 2018 to 2019 (Dollars in millions) 2020 2019 2018 Change Change Interest income and other income (expense), net $ 17.5 $ 27.4 $ 32.6 (36.0) % (16.1) % Interest expense (10.3) (9.9) (16.3) 5.0 % (39.5) % Interest and other income (expense), net $ 7.2 $ 17.5 $ 16.3 (59.0) % 7.2 % Interest income and other income (expense), net, primarily consists of interest income of $14.2 million, $20.4 million and $27.2 million for the years ended December 31, 2020, 2019 and 2018, respectively, due to the significant financing component 36 of licensing agreements. Interest income and other income (expense), net, also includes interest income generated from investments in high quality fixed income securities and any gains or losses from the re-measurement of our monetary assets or liabilities denominated in foreign currencies. Interest expense for all periods disclosed primarily consists of interest expense associated with the non-cash interest expense related to the amortization of the debt discount and issuance costs on the 1.375% convertible senior notes due 2023 (the “2023 Notes”) and the 1.125% convertible senior notes due 2018 (the “2018 Notes”), as well as the coupon interest related to these notes. Interest expense decreased in 2019 as compared to the same period in 2018 primarily due to the 2018 Notes maturing in the third quarter of 2018. We expect our non-cash interest expense to increase steadily as the notes reach maturity. Refer to Note 12, “Convertible Notes,” of Notes to Consolidated Financial Statements of this Form 10-K for additional details. Prior to 2019, interest expense also included the interest expense associated with our previous imputed facility lease obligations on the Sunnyvale and Ohio facilities. For the year ended December 31, 2018, we recognized $4.3 million of interest expense in connection with the imputed financing obligations in our statements of operations. In accordance with the adoption of ASC 842, the New Leasing Standard, we were required to derecognize our previous Sunnyvale and Ohio facilities as imputed facility obligations (as accounted for under the previous leasing standard) and recognize these facilities as operating leases. This change resulted in no longer recognizing interest expense associated with these imputed facility lease obligations, but instead, recognizing lease expense which would be included in operating costs and expenses. Provision for income taxes Years Ended December 31, 2019 to 2020 2018 to 2019 (Dollars in millions) 2020 2019 2018 Change Change Provision for income taxes $ 4.0 $ 3.4 $ 87.3 16.9 % (96.1) % Effective tax rate (10.0) % (3.9) % (123.6) % Our effective tax rate for the year ended December 31, 2020 differed from the U.S. statutory rate primarily due to the expiration of foreign tax credits, partially offset by the change in the valuation allowance against U.S. deferred tax assets. Our effective tax rate for the year ended December 31, 2019 was different from the U.S. statutory rate primarily due to the full valuation allowance on the current year tax loss. Our effective tax rate for the year ended December 31, 2018 was different from the U.S. statutory rate primarily due to the establishment of a full valuation allowance on U.S. federal deferred tax assets. We recorded a provision for incomes taxes of $4.0 million for the year ended December 31, 2020, which was primarily comprised of taxes on foreign earnings, the full valuation allowance on U.S. federal deferred tax assets, withholding tax expense, tax expense from the amortization of indefinite-lived intangibles, partially offset by a partial California deferred tax asset valuation allowance release. For the year ended December 31, 2020, we paid withholding taxes of $19.7 million. We recorded a provision for incomes taxes of $3.4 million for the year ended December 31, 2019, which was primarily comprised of taxes on foreign earnings, the full valuation allowance on U.S. federal deferred tax assets, withholding tax expense, and acquisition-related impacts. For the year ended December 31, 2019, we paid withholding taxes of $17.1 million. We recorded a provision for incomes taxes of $87.3 million for the year ended December 31, 2018, which was primarily comprised of the full valuation allowance on U.S. federal deferred tax assets. For the year ended December 31, 2018, we paid withholding taxes of $20.4 million. We periodically evaluate the realizability of our net deferred tax assets based on all available evidence, both positive and negative. During the third quarter of 2018, we assessed the changes in our underlying facts and circumstances and evaluated the realizability of our existing deferred tax assets based on all available evidence, both positive and negative, and the weight accorded to each, and concluded a full valuation allowance associated with U.S. federal and California deferred tax assets was appropriate. During 2020, as a result of the enactment of California A.B. 85 and the temporary suspension of California net operating loss utilization for tax years 2020 through 2022, we released $0.6 million of the valuation allowance on our deferred tax asset for California research and development tax credits. We continue to maintain a full valuation allowance on the remainder of our California and U.S. federal deferred tax assets as we do not expect to be able to fully utilize them. 37 Liquidity and Capital Resources (In millions) December 31, 2020 December 31, 2019 Cash and cash equivalents $ 136.1 $ 102.2 Marketable securities 366.5 305.5 Total cash, cash equivalents, and marketable securities $ 502.6 $ 407.7 Years Ended December 31, (In millions) 2020 2019 2018 Net cash provided by operating activities $ 185.5 $ 128.5 $ 87.1 Net cash used in investing activities $ (90.4) $ (141.5) $ (68.0) Net cash used in financing activities $ (61.2) $ (0.3) $ (127.7) Liquidity We currently anticipate that existing cash, cash equivalents and marketable securities balances and cash flows from operations will be adequate to meet our cash needs for at least the next 12 months. Additionally, the majority of our cash and cash equivalents is in the United States. Our cash needs for the year ended December 31, 2020 were funded primarily from cash collected from our customers. We do not anticipate any liquidity constraints as a result of either the current credit environment or investment fair value fluctuations. Additionally, we have the intent and ability to hold our debt investments that have unrealized losses in accumulated other comprehensive gain (loss) for a sufficient period of time to allow for recovery of the principal amounts invested. Further, we have no significant exposure to European sovereign debt. We continually monitor the credit risk in our portfolio and mitigate our credit risk exposures in accordance with our policies. As a part of our overall business strategy, from time to time, we evaluate businesses and technologies for potential acquisitions that are aligned with our core business and designed to supplement our growth. To provide us with more flexibility in returning capital to our stockholders, on October 29, 2020, our Board approved the 2020 Repurchase Program authorizing the repurchase of up to an aggregate of 20.0 million shares. Share repurchases under the 2020 Repurchase Program may be made through the open market, established plans or privately negotiated transactions in accordance with all applicable securities laws, rules, and regulations. There is no expiration date applicable to the 2020 Repurchase Program. The 2020 Repurchase Program replaced the previous 2015 Repurchase Program approved by our Board in January 2015 and canceled the remaining shares outstanding as part of the previous authorization. On November 11, 2020, we entered into the 2020 ASR Program with Deutsche Bank. The 2020 ASR Program was part of the broader share repurchase program previously authorized by our Board on October 29, 2020. Under the 2020 ASR Program, we pre-paid to Deutsche Bank the $ 50.0 million purchase price for our common stock and, in turn, we received an initial delivery of approximately 2.6 million shares of our common stock from Deutsche Bank in the fourth quarter of 2020, which were retired and recorded as a $ 40.0 million reduction to stockholders’ equity. The remaining $ 10.0 million of the initial payment was recorded as a reduction to stockholders’ equity as an unsettled forward contract indexed to our stock. As of December 31, 2020, there remained an outstanding authorization to repurchase approximately 17.4 million shares of our outstanding common stock under the 2020 Repurchase Plan. Refer to “Share Repurchase Program” below. Operating Activities Cash provided by operating activities of $185.5 million for the year ended December 31, 2020 was primarily attributable to the cash generated from customer licensing, product sales and engineering services fees. Changes in operating assets and liabilities for the year ended December 31, 2020 primarily included decreases in unbilled receivables, accounts receivable, prepaids and other current assets, and an increase in accrued salaries and benefits, offset by a decrease in income taxes payable and an increase in inventories. Cash provided by operating activities of $128.5 million for the year ended December 31, 2019 was primarily attributable to the cash generated from customer licensing, technology and software licenses and related implementation, support and maintenance fees, product sales, and engineering services fees. Changes in operating assets and liabilities for the year ended December 31, 2019 primarily included decreases in accounts receivable, unbilled receivables and deferred revenue, offset by increases in prepaids and other current assets, inventories and accrued salaries and benefits. 38 Cash provided by operating activities of $87.1 million for the year ended December 31, 2018 was primarily attributable to the cash generated from customer licensing, technology and software licenses and related implementation, support and maintenance fees, product sales and engineering services fees. Changes in operating assets and liabilities for the year ended December 31, 2018 primarily included increases in unbilled receivables, accounts receivable and prepaids and other current assets, offset by decreases in accounts payable and accrued salaries and benefits and other liabilities. Investing Activities Cash used in investing activities of $90.4 million for the year ended December 31, 2020 consisted of purchases of available-for-sale marketable securities of $899.0 million, $29.7 million paid to acquire property, plant and equipment, and $1.1 million paid to settle a net working capital adjustment related to the divestiture of our Payments and Ticketing businesses, offset by proceeds from the maturities and sale of available-for-sale marketable securities of $817.8 million and $21.6 million, respectively. Cash used in investing activities of $141.5 million for the year ended December 31, 2019 primarily consisted of purchases of available-for-sale marketable securities of $657.4 million, $21.9 million paid for the acquisition of Northwest Logic, net of cash acquired of $0.1 million, $45.0 million paid for the acquisition of the Secure Silicon IP and Protocols business from Verimatrix, formerly Inside Secure, and $6.5 million paid to acquire property, plant and equipment, offset by proceeds from the maturities and sale of available-for-sale marketable securities of $507.4 million and $6.8 million, respectively, and net proceeds of $76.0 million from the divestiture of our Payments and Ticketing businesses. Cash used in investing activities of $68.0 million for the year ended December 31, 2018 primarily consisted of purchases of available-for-sale marketable securities of $282.1 million, $10.8 million paid to acquire property, plant and equipment and $3.0 million paid for investment in a privately held company, offset by proceeds from the maturities of available-for-sale marketable securities of $223.1 million, proceeds from the sale of assets held for sale of $3.8 million and proceeds from the sale of an equity security of $1.3 million. Financing Activities Cash used in financing activities of $61.2 million for the year ended December 31, 2020 was primarily due to an aggregate payment of $50.0 million to Deutsche Bank as part of the 2020 ASR Program. We also paid $13.2 million under installment payment arrangements to acquire fixed assets, $9.4 million in payments of taxes on restricted stock units and $0.1 million in fees related to the 2020 ASR Program, offset by $11.5 million in proceeds from the issuance of common stock under equity incentive plans. Cash used in financing activities was $0.3 million for the year ended December 31, 2019 and was primarily due to $8.4 million in payments under installment payment arrangements to acquire fixed assets and $7.0 million in payments of taxes on restricted stock units, offset by $15.1 million proceeds from the issuance of common stock under equity incentive plans. Cash used in financing activities was $127.7 million for the year ended December 31, 2018 and was primarily due to the repayment of the remaining aggregate principal of the 2018 Notes amounting to $81.2 million, which became due in August 2018, an aggregate payment of $50.0 million to Citibank N.A., as part of our accelerated share repurchase program, and $6.8 million in payments of taxes on restricted stock units, offset by $11.4 million proceeds from the issuance of common stock under equity incentive plans. Contractual Obligations On December 15, 2009, we entered into a lease agreement for approximately 125,000 square feet of office space located at 1050 Enterprise Way in Sunnyvale, California, which commenced on July 1, 2010 and expired on June 30, 2020. The office space was used for our corporate headquarters, as well as engineering, sales, marketing and administrative operations and activities. On July 8, 2019, we entered into a definitive triple net space lease agreement with 237 North First Street Holdings, LLC (the “Landlord”), whereby we leased office space located at 4453 North First Street in San Jose, California, (the “Lease”). In April 2020, the lease was amended for certain terms (the “Amended Lease”). The Amended Lease includes approximately 90,000 square feet of office space, which serves as our corporate headquarters and includes engineering, sales, marketing and administrative functions. The Amended Lease has a term of 128 months from the amended commencement date in April 2020. The starting rent of the Amended Lease is approximately $3.26 per square foot on a triple net basis. The annual base rent increases each year to certain fixed amounts over the course of the term as set forth in the Amended Lease and will be $4.38 per square foot in the final year of the Amended Lease term. In addition to the base rent, we will also pay operating expenses, insurance expenses, real estate taxes, and a management fee under the Amended Lease. The Amended Lease also allows for an option to expand, wherein we have the right of first refusal to rent additional space in the building. We have a one-time option 39 Table of Contents to extend the Amended Lease for a period of 60 months and may elect to terminate the Amended Lease, via written notice to the Landlord, in the event the office space is damaged or destroyed. Total required payments under the Amended Lease are approximately $41 million. Pursuant to the terms of the Amended Lease, the landlord agreed to reimburse us up to $9.0 million, related to a tenant improvement allowance. On November 17, 2017, we entered into an Indenture with U.S. Bank, National Association, as trustee, relating to the issuance by us of $172.5 million aggregate principal amount of the 2023 Notes. Refer to Note 12, “Convertible Notes,” of Notes to Consolidated Financial Statements of this Form 10-K for additional details. As of December 31, 2020, our material contractual obligations were as follows: (In thousands) Total 2021 2022 2023 2024 2025 Contractual obligations (1) (2) (3) Software licenses (4) $ 18,970 $ 12,541 $ 6,429 $ — $ — $ — Acquisition retention bonuses (5) 6,370 3,370 3,000 — — — Convertible notes 172,500 — — 172,500 — — Interest payments related to convertible notes 5,936 2,372 2,372 1,192 — — Total $ 203,776 $ 18,283 $ 11,801 $ 173,692 $ — $ — ______________________________________ (1) The above table does not reflect possible payments in connection with unrecognized tax benefits of approximately $25.5 million including $23.6 million recorded as a reduction of long-term deferred tax assets and $1.9 million in long-term income taxes payable, as of December 31, 2020. As noted in Note 19, “Income Taxes,” of Notes to Consolidated Financial Statements of this Form 10-K, although it is possible that some of the unrecognized tax benefits could be settled within the next 12 months, we cannot reasonably estimate the outcome at this time. (2) For our lease commitments as of December 31, 2020, refer to Note 10, “Leases,” of Notes to Consolidated Financial Statements of this Form 10-K. (3) Our other contractual obligations as of December 31, 2020 were not material. (4) We have commitments with various software vendors for agreements generally having terms longer than one year. (5) In connection with the acquisitions of Northwest Logic in August 2019 and the Secure Silicon IP and Protocols business in December 2019, we are obligated to pay retention bonuses to certain employees subject to certain eligibility and acceleration provisions including the condition of employment. Share Repurchase Program On January 21, 2015, our Board approved a share repurchase program authorizing the repurchase of up to an aggregate of 20.0 million shares (the “2015 Repurchase Program”). Share repurchases under the 2015 Repurchase Program were made through the open market, established plans or privately negotiated transactions in accordance with all applicable securities laws, rules, and regulations. During the years ended December 31, 2020 and 2019, we did not repurchase any shares of our common stock under the 2015 Repurchase Program. On October 29, 2020, our Board approved the 2020 Repurchase Program authorizing the repurchase of up to an aggregate of 20.0 million shares. Share repurchases under the 2020 Repurchase Program may be made through the open market, established plans or privately negotiated transactions in accordance with all applicable securities laws, rules, and regulations. There is no expiration date applicable to the 2020 Repurchase Program. The 2020 Repurchase Program replaced the previous program approved by the Board in January 2015 and canceled the remaining shares outstanding as part of the previous authorization. On November 11, 2020, we entered into the 2020 ASR Program with Deutsche Bank. The 2020 ASR Program was part of the broader 2020 Repurchase Program. Under the 2020 ASR Program, we pre-paid to Deutsche Bank the $50.0 million purchase price for our common stock and, in turn, we received an initial delivery of approximately 2.6 million shares of our common stock from Deutsche Bank in the fourth quarter of 2020, which were retired and recorded as a $40.0 million reduction to stockholders’ equity. The remaining $10.0 million of the initial payment was recorded as a reduction to stockholders’ equity as an unsettled forward contract indexed to our stock. The number of shares to be ultimately purchased by us will be determined based on the volume-weighted-average price of the common stock during the terms of the transaction, minus an agreed upon discount between the parties. The 2020 ASR 40 Program is expected to be completed within six months from the beginning of the program. There were no other repurchases of our common stock during 2020. As of December 31, 2020, there remained an outstanding authorization to repurchase approximately 17.4 million shares of our outstanding common stock under the current share repurchase program. We record share repurchases as a reduction to stockholders’ equity. We record a portion of the purchase price of the repurchased shares as an increase to accumulated deficit when the price of the shares repurchased exceeds the average original proceeds per share received from the issuance of common stock. During the year ended December 31, 2020, the cumulative price of $31.5 million was recorded as an increase to accumulated deficit. Warrants In connection with the 2023 Notes, we separately entered into privately negotiated warrant transactions, whereby we sold to the Counterparties warrants (the “Warrants”) to acquire, collectively, subject to anti-dilution adjustments, approximately 9.1 million shares of our common stock at an initial strike price of approximately $23.30 per share, which represents a premium of 60% over the last reported sale price of our common stock of $14.56 on November 14, 2017. We received aggregate proceeds of approximately $23.2 million from the sale of the Warrants to the Counterparties. The Warrants are separate transactions and are not part of the 2023 Notes or Convertible Note Hedge Transactions. Holders of the 2023 Notes and Convertible Note Hedge Transactions will not have any rights with respect to the Warrants. Refer to Note 12, “Convertible Notes,” of Notes to Consolidated Financial Statements of this Form 10-K for additional details. Critical Accounting Policies and Estimates The discussion and analysis of our financial condition and results of operations are based upon our consolidated financial statements, which have been prepared in accordance with accounting principles generally accepted in the United States. 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. On an ongoing basis, we evaluate our estimates, including those related to revenue recognition, investments, income taxes, litigation and other contingencies. We base our estimates on historical experience and on various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates under different assumptions or conditions. We believe the following critical accounting policies affect our more significant judgments and estimates used in the preparation of our consolidated financial statements. Revenue Recognition Overview We recognize revenue upon transfer of control of promised goods and services in an amount that reflects the consideration we expect to receive in exchange for those goods and services. Substantially all of the goods and services are distinct and are accounted for as separate performance obligations. Where an arrangement includes multiple performance obligations, the transaction price is allocated to these on a relative standalone selling price basis. We have established standalone selling prices for all of our offerings - specifically, the same pricing methodology is consistently applied to all licensing arrangements; all services offerings are priced within tightly controlled bands and all contracts that include support and maintenance state a renewal rate or price that is systematically enforced. Our revenue consists of royalty, product and contract and other revenue. Royalty revenue consists of patent and technology license royalties. Products primarily consist of memory interface chips sold directly and indirectly to module manufacturers and OEMs worldwide through multiple channels, including our direct sales force and distributors. Contract and other revenue consists of software license fees, engineering fees associated with integration of our technology solutions into our customers’ products and support and maintenance fees. Royalty Revenue Our patent and technology licensing arrangements generally range between one year and ten years in duration and generally grant the licensee the right to use our entire IP portfolio as it evolves over time. These arrangements do not typically grant the licensee the right to terminate for convenience and where such rights exist, termination is prospective, with no refund of fees already paid by the licensee. There is no interdependency or interrelation between the IP included in the portfolio licensed upon 41 contract inception and any IP subsequently made available to the licensee, and we would be able to fulfill our promises by transferring the portfolio and the additional IP use rights independently. However, the numbers of additions to, and removals from the portfolio (for example when a patent expires and renewal is not granted to us) in any given period have historically been relatively consistent; as such, we do not allocate the transaction price between the rights granted at contract inception and those subsequently granted over time as a function of these additions. Patent and technology licensing arrangements result in fixed payments received over time, with guaranteed minimum payments on occasion, variable payments calculated based on the licensee’s sale or use of the IP, or a mix of fixed and variable payments. • For fixed-fee arrangements (including arrangements that include minimum guaranteed amounts), we recognize revenue upon control over the underlying IP use right transferring to the licensee, net of the effect of significant financing components calculated using customer-specific, risk-adjusted lending rates ranging between 3% and 5%, with the related interest income being recognized over time on an effective rate basis. Where a licensee has the contractual right to terminate a fixed-fee arrangement for convenience without any substantive penalty payable upon such termination, we only recognize revenue on contracts in which the parties have present enforceable rights and obligations and that are due and payable. • For variable arrangements, we recognize revenue based on an estimate of the licensee’s sale or usage of the IP during the period of reference, typically quarterly, with a true-up recorded when we receive the actual royalty report from the licensee. Product Revenue Product revenue is recognized upon shipment of product to customers, net of accruals for estimated sales returns and allowances, and to distributors, net of accruals for price protection and rights of return on products unsold by the distributors. To date, none of these accruals have been significant. We transact with direct customers primarily pursuant to standard purchase orders for delivery of products and generally allow customers to cancel or change purchase orders within limited notice periods prior to the scheduled shipment date. Contract and Other Revenue Contract and other revenue consists of software license fees and engineering fees associated with integration of our technology solutions into our customers’ related support and maintenance. An initial software arrangement generally consists of a term-based or perpetual license, significant software customization services and support and maintenance services that include post-implementation customer support and the right to unspecified software updates and enhancements on a when and if available basis. We recognize license and customization services revenue based on an over time model, measured using the input method. License and customization services revenue is reported as part of contract and other revenue. Due to the nature of the work performed in these arrangements, the estimation of the over time model is complex and involves significant judgment. The key factor reviewed by us to estimate costs to complete each contract is the estimated man-months necessary to complete the project. We recognize license renewal revenue at the beginning of the renewal period. Significant Judgments Historically and with the exception noted below, no significant judgment has generally been required in determining the amount and timing of revenue from our contracts with customers. • We have adequate tools and controls in place, and substantial experience and expertise in timely and accurately tracking man-months incurred in completing customization and other professional services, and quantifying changes in estimates. Key estimates used in recognizing revenue predominantly consist of the following: • For fixed-fee arrangements in which cash is being received over a period exceeding a year, we calculate a customer-specific lending rate using a Daily Treasury Yield Curve Rate that changes depending on the date on which the licensing arrangement was entered into and the term (in years) of the arrangement, and take into consideration a licensee-specific risk profile determined based on a review of the licensee’s “Full Company View” Dun & Bradstreet report obtained on the date the licensing arrangement was signed by the parties, with a risk premium being added to the Daily Treasury Yield Curve Rate considering the overall business risk, financing strength and risk indicators, as listed. • We recognize revenue on variable fee licensing arrangements on the basis of estimates. 42 Goodwill Goodwill represents the excess of the purchase price over the fair value of the net tangible and identifiable intangible assets acquired in each business combination. Goodwill is not subject to amortization, but is subject to at least an annual assessment for impairment. We perform our impairment analysis of goodwill on an annual basis during the fourth quarter of the year unless conditions arise that warrant a more frequent evaluation. When goodwill is assessed for impairment, we have the option to perform an assessment of qualitative factors of impairment (optional assessment) prior to necessitating a quantitative impairment test. Should the optional assessment be used for any given year, qualitative factors to consider for a reporting unit include: cost factors; financial performance; legal, regulatory, contractual, political, business, or other factors; entity specific factors; industry and market considerations; macroeconomic conditions; and other relevant events and factors affecting the reporting unit. If we determine in the qualitative assessment that it is more likely than not that the fair value of the reporting unit is less than its carrying value, a quantitative test is then performed. Otherwise, no further testing is required. For a reporting unit tested using a quantitative approach, we compare the fair value of the reporting unit with the carrying amount of the reporting unit, including goodwill. The fair value of the reporting unit is estimated using an income approach. Under the income approach, we measure fair value of the reporting unit based on a projected cash flow method using a discount rate determined by our management which is commensurate with the risk inherent in its current business model. Our discounted cash flow projections are based on its annual financial forecasts developed internally by management for use in managing our business. If the fair value of the reporting unit exceeds its carrying value, goodwill is not impaired and no further testing is required. If the fair value of the reporting unit is less than the carrying value, then the amount of goodwill impairment will be the amount by which the reporting unit’s carrying value exceeds its fair value, not to exceed the carrying amount of goodwill. Intangible Assets Intangible assets are comprised of existing technology, customer contracts and contractual relationships, and other definite-lived and indefinite-lived intangible assets. Identifiable intangible assets resulting from the acquisitions of entities accounted for using the purchase method of accounting are estimated by management based on the fair value of assets received. Identifiable definite-lived intangible assets are being amortized over the period of estimated benefit using the straight-line method and estimated useful lives ranging from six months to ten years. We amortize definite-lived assets over their estimated useful lives. We evaluate definite-lived and indefinite-lived assets for impairment whenever events or changes in circumstances indicate the carrying value of an asset may not be recoverable. The carrying value is not recoverable if it exceeds the undiscounted cash flows resulting from the use of the asset and its eventual disposition. Our estimates of future cash flows attributable to our assets require significant judgment based on our historical and anticipated results and are subject to many factors. Factors we consider important which could trigger an impairment review include significant negative industry or economic trends, significant loss of clients, and significant changes in the manner of our use of the acquired assets or the strategy for our overall business. When we determine that the carrying value of the assets may not be recoverable based upon the existence of one or more of the above indicators of impairment, we measure the potential impairment based on a projected discounted cash flow method using a discount rate determined by our management to be commensurate with the risk inherent in our current business model. An impairment loss is recognized only if the carrying amount of the asset is not recoverable and exceeds its fair value. Different assumptions and judgments could materially affect the calculation of the fair value of our assets. Acquired indefinite-lived intangible assets related to our IPR&D are capitalized and subject to impairment testing until completion or abandonment of the projects. Upon successful completion of each project, we make a separate determination of the useful life of the acquired indefinite-lived intangible assets and the related amortization is recorded as an expense over the estimated useful life of the specific projects. Indefinite-lived intangible assets are subject to at least an annual assessment for impairment, applying a fair-value based test. Under the income approach, we measure fair value of the indefinite-lived intangible assets based on a projected cash flow method using a discount rate determined by our management which is commensurate with the risk inherent in our current business model. Our discounted cash flow projections are based on our annual financial forecasts developed internally by our management for use in managing our business. If the fair value of the indefinite-lived intangible assets exceeds its carrying value, the indefinite-lived intangible assets are not impaired and no further testing is required. If the implied fair value of the indefinite-lived intangible assets is less than the carrying value, the difference is recorded as an impairment loss. 43 Table of Contents Income Taxes As part of preparing our consolidated financial statements, we are required to calculate the income tax expense (benefit) which relates to the pretax income or loss for the period. In addition, we are required to assess the realization of the deferred tax asset or liability to be included on the consolidated balance sheet as of the reporting dates. As of December 31, 2020, our consolidated balance sheet included net deferred tax assets, before valuation allowance, of approximately $164.3 million, which consists of net operating loss carryovers, tax credit carryovers, amortization, employee stock-based compensation expenses, certain liabilities and certain assets. As of December 31, 2020, we have a valuation allowance of $174.3 million resulting in net deferred tax liabilities of $10.0 million. We maintain liabilities for uncertain tax positions within our long-term income taxes payable accounts and as a reduction to existing deferred tax assets or other refundable taxes to the extent tax attributes are available to offset such liabilities. These liabilities involve judgment and estimation and are monitored by us based on the best information available including changes in tax regulations, the outcome of relevant court cases and other information. The calculation of our tax liabilities involves uncertainties in the application of complex tax law and regulations in a multitude of jurisdictions. Although ASC 740, “Income Taxes,” provides further clarification on the accounting for uncertainty in income taxes, significant judgment is required by us. If the ultimate resolution of tax uncertainties is different from what is currently estimated, it could materially affect income tax expense. Stock-Based Compensation We maintain stock plans covering a broad range of potential equity grants including stock options, nonvested equity stock and equity stock units and performance-based instruments. In addition, we sponsor an Employee Stock Purchase Plan (“ESPP”), whereby eligible employees are entitled to purchase Common Stock semi-annually, by means of limited payroll deductions, at a 15% discount from the fair market value of the Common Stock as of specific dates. The accounting guidance for share-based payments requires the measurement and recognition of compensation expense in our statement of operations for all share-based payment awards made to our employees, directors and consultants including employee stock options, nonvested equity stock and equity stock units, and employee stock purchase grants. Stock-based compensation expense is measured at grant date, based on the estimated fair value of the award, reduced by an estimate of the annualized rate of expected forfeitures, and is recognized as expense over the employees’ expected requisite service period, generally using the straight-line method. In addition, the accounting guidance for share-based payments requires the benefits of tax deductions in excess of recognized compensation expense to be reported as a financing cash flow. Our forfeiture rate represents the historical rate at which our stock-based awards were surrendered prior to vesting. The accounting guidance for share-based payments requires forfeitures to be estimated at the time of grant and revised on a cumulative basis, if necessary, in subsequent periods if actual forfeitures differ from those estimates. Refer to Note 14, “Equity Incentive Plans and Stock-Based Compensation,” of Notes to Consolidated Financial Statements of this Form 10-K for more information regarding the valuation of stock-based compensation. Business Combinations We account for acquisitions of businesses using the purchase method of accounting, which requires us to recognize separately from goodwill the assets acquired and the liabilities assumed at their acquisition date fair values. While we use our best estimates and assumptions to accurately value assets acquired and liabilities assumed at the acquisition date as well as contingent consideration, where applicable, the 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, we may record adjustments to the assets acquired and liabilities assumed with the corresponding offset to goodwill. Upon the conclusion of the measurement period or final determination of the values of assets acquired or liabilities assumed, whichever comes first, any subsequent adjustments are recorded to our consolidated statements of operations. Accounting for business combinations requires us to make significant estimates and assumptions, especially at the acquisition date including our estimates for intangible assets, contractual obligations assumed and pre-acquisition contingencies where applicable. Although we believe the assumptions and estimates made in the past have been reasonable and appropriate, they are based in part on historical experience and information obtained from the management of the acquired companies and are inherently uncertain. Significant estimates and assumptions made by us in estimating the fair value of the existing technologies included revenue growth rates, operating expense margins, technology obsolescence rates and discount rates. Unanticipated events and circumstances may occur that may affect the accuracy or validity of such assumptions, estimates or actual results. 44 Recent Accounting Pronouncements Refer to Note 3, “Recent Accounting Pronouncements,” of Notes to Consolidated Financial Statements of this Form 10-K for a full description of recent accounting pronouncements including the respective expected dates of adoption.