Stockholders' Equity and Stock-Based Compensation of the Notes to Consolidated Financial Statements included in Part II, Item 8, of this Annual Report on Form 10-K for further discussion. 64 Material Cash Requirements Our material cash requirements will have an impact on our future liquidity. Our material cash requirements represent material expected or contractually committed future payment obligations.
Stockholders' Equity and Stock-Based Compensation of the Notes to Consolidated Financial Statements included in Part II, Item 8, of this Annual Report on Form 10-K for further discussion. Material Cash Requirements Our material cash requirements will have an impact on our future liquidity. Our material cash requirements represent material expected or contractually committed future payment obligations.
We base our estimates, assumptions and judgments on 65 historical experience and on various other factors that we believe to be reasonable under the circumstances. Different assumptions and judgments would change the estimates used in the preparation of our consolidated financial statements, which, in turn, could change the results from those reported.
We base our estimates, assumptions and judgments on historical experience and on various other factors that we believe to be reasonable under the circumstances. Different assumptions and judgments would change the estimates used in the preparation of our consolidated financial statements, which, in turn, could change the results from those reported.
We expect our research and development expenses to increase in absolute dollars as we continue to invest in software development in order to expand the capabilities of our cloud networking platform, introduce new products and features, and continue to invest in our technology.
We expect our research and development expenses to increase in absolute dollars as we continue to invest in research and development in order to expand the capabilities of our cloud networking platform, introduce new products and features, and continue to invest in our technology.
If actual market demand conditions or supplier execution on commitments are less favorable than those projected by management, which may be caused by factors within and/or outside of our control, we may be required to increase our inventory write-downs and liabilities to our contract manufacturers and suppliers, which could have an adverse impact on our gross margins and profitability.
If actual market demand conditions or supplier execution on commitments are less favorable than those projected by management, which may be caused by factors within and/or outside of our control, we may be required to increase our inventory write-downs and liabilities to our suppliers, which could have an adverse impact on our gross margins and profitability.
Recent Accounting Pronouncements Refer to the subheading titled “ Recently Adopted Accounting Pronouncements” in Note 1. Organization and Summary of Significant Accounting Policies of the Notes to Consolidated Financial Statements included in Part II, Item 8, of this Annual Report on Form 10-K. 67
Recent Accounting Pronouncements Refer to the subheading titled “ Recently Adopted Accounting Pronouncements” in Note 1. Organization and Summary of Significant Accounting Policies of the Notes to Consolidated Financial Statements included in Part II, Item 8, of this Annual Report on Form 10-K. 62
Provision for Income Taxes (in thousands, except percentages) We operate in a number of tax jurisdictions and are subject to taxes in each country or jurisdiction in which we conduct business. Earnings from our non-U.S. activities are subject to local country income tax and may also be subject to U.S. income tax.
Provision for Income Taxes (in millions, except percentages) We operate in a number of tax jurisdictions and are subject to taxes in each country or jurisdiction in which we conduct business. Earnings from our non-U.S. activities are subject to local country income tax and may also be subject to U.S. income tax.
These cash inflows were partially offset by a $234.2 million increase in other assets driven by increased deferred cost of sales associated with higher product revenue deferrals, an increase in accounts receivable of $106.1 million due to increased product and service billings and a $66.5 million increase in income tax payments due to timing.
These cash inflows were partially offset by a $234.2 million increase in other assets driven by increased deferred cost of goods sold associated with higher product revenue deferrals, an increase in accounts receivable of $106.1 million due to increased product and service billings and a $66.5 million increase in income tax payments due to timing.
Off-balance Sheet Arrangements As of December 31, 2024, we did not have any relationships with any unconsolidated entities or financial partnerships, such as entities often referred to as structured finance or special purpose entities, that would have been established for the purpose of facilitating off-balance sheet arrangements or other contractually narrow or limited purposes.
Off-balance Sheet Arrangements 60 As of December 31, 2025, we did not have any relationships with any unconsolidated entities or financial partnerships, such as entities often referred to as structured finance or special purpose entities, that would have been established for the purpose of facilitating off-balance sheet arrangements or other contractually narrow or limited purposes.
Given the timing and prioritization of customer orders and shipment patterns, as well as the timing and outcome of customer trials and contracts with acceptance periods, near term revenue trends may not be reflective of current demand levels, and as discussed above will also benefit from demand/deployment plans that have been previously committed.
Given the timing and prioritization of customer orders and shipment patterns, as well as the timing and outcome of customer trials and contracts with acceptance periods, near term revenue trends may not be reflective of current demand levels and may benefit from demand/deployment plans that have been previously committed.
Research and development expenses consist primarily of personnel costs, prototype expenses, third-party engineering costs, and an allocated portion of facility and IT costs. Our research and development efforts are focused on new product development and maintaining and developing additional functionality for our existing products, including new releases and upgrades to our EOS software and applications.
Research and development expenses consist primarily of personnel costs, new product introduction costs and an allocated portion of facility and IT costs. Our research and development efforts are focused on new product development and maintaining and developing additional functionality for our existing products, including new releases and upgrades to our EOS software and applications.
Gross margin, or gross profit as a percentage of revenue, has been and will continue to be affected by a variety of factors, including pricing pressure on our products and services due to competition, the mix of sales to large customers who generally receive lower pricing, the mix of products sold, manufacturing-related costs, including costs associated with supply chain sourcing activities, merchant silicon costs, and excess/obsolete inventory and supplier liability charges.
Gross margin, or gross profit as a percentage of revenue, has been and will continue to be affected by a variety of factors, including pricing pressure on our products and services due to competition, the mix of sales to large customers who generally receive lower pricing, the mix of products sold, manufacturing-related costs, including costs associated with our manufacturing operations personnel, inflationary pressure and scarcity of materials in our supply chain, merchant silicon costs, 54 and excess/obsolete inventory and supplier liability charges.
The increase was primarily due to a $64.9 million increase in personnel costs driven by an increase in headcount, and a $52.3 million increase in new product introduction costs, including non-recurring engineering costs and prototype expenses as we expand our product portfolio. Sales and marketing.
The increase was primarily due to a $64.9 million increase in personnel costs driven by an increase in headcount, and a $52.3 million increase in new product introduction costs, including third-party engineering costs and prototype expenses as we expand our product portfolio.
As of December 31, 2024, we had $3.1 billion of such purchase obligations, of which $2.8 billion are expected to be received within 12 months, and $0.3 billion are e xpected to be received after one year.
As of December 31, 2025, we had $6.8 billion of such purchase obligations, of which $6.3 billion are expected to be received within 12 months, and $0.5 billion are e xpected to be received after one year.
These increases were driven by a corresponding increase in product and service revenues, partially offset by reductions of $180.4 million in net excess/obsolete inventory and supplier liability charges for the year ended December 31, 2024 compared to 2023.
These increases were driven by a corresponding increase in product and service revenues, partially offset by reductions of $180.4 million in net excess/obsolete inventory and supplier liability charges for the year ended December 31, 2024 compared to 2023. Gross margin increased from 61.9% for the year ended December 31, 2023 to 64.1% for the year ended December 31, 2024.
During the year ended December 31, 2024, we repurchased a total of $279.0 million of our common stock under our New Repurchase Program and $144.6 million of our common stock under our Prior Repurchase Program. As of December 31, 2024, the remaining authorized amount for stock repurchases under the New Repurchase Program was approximately $921.0 million. Refer to Note 6.
During the year ended December 31, 2025, we repurchased a total of $921.0 million of our common stock under our Prior Repurchase Program and $682.1 million of our common stock under our New Repurchase Program. As of December 31, 2025, the remaining authorized amount for stock repurchases under the New Repurchase Program was approximately $817.9 million. Refer to Note 6.
Cash Flows from Investing Activities Our investing activities primarily consist of our marketable securities investments, business combinations, and capital expenditures. During the year ended December 31, 2024, cash used in investing activities was $2.5 billion, consisting of purchases of available-for-sale securities of $4.5 billion, partially offset by proceeds of $2.1 billion from maturities and sales of marketable securities.
During the year ended December 31, 2024, cash used in investing activities was $2.5 billion, consisting of purchases of available-for-sale securities of $4.5 billion, partially offset by proceeds of $2.1 billion from maturities and sales of marketable securities.
International revenu es as a percentage of our total revenues decreased fro m 20.6% in 2023 to 18.2% in 2024, which was primarily driven by changes in the geographic mix of sales to our large global customers.
Non - Americas revenues as a percentage of our total revenues decreased from 20.6% in 2023 to 18.2% in 2024, which was primarily driven by changes in the geographic mix of sales to our large global customers.
Year Ended December 31, 2024 2023 Change in $ % of Revenue $ % of Revenue $ % Provision for income taxes $ 412,980 5.9 % $ 334,705 5.7 % $ 78,275 23.4 % Effective tax rate 12.6 % 13.8 % Our provision for income taxes increased for the year ended December 31, 2024, as compared to 2023, while our effective tax rate decreased for the year ended December 31, 2024, as compared to 2023.
Provision for Income Taxes (in millions, except percentages) Year Ended December 31, 2024 2023 Change in $ % of Revenue $ % of Revenue $ % Provision for income taxes $ 413.0 5.9 % $ 334.7 5.7 % $ 78.3 23.4 % Effective tax rate 12.6 % 13.8 % Our provision for income taxes increased for the year ended December 31, 2024, as compared to 2023, while our effective tax rate decreased for the year ended December 31, 2024, as compared to 2023.
The Repurchase Programs do not obligate us to acquire any of our common stock, and may be suspended or discontinued by the company at any time without prior notice.
The New Repurchase Program does not oblige us to acquire any of our common stock and may be suspended or discontinued by the Company at any time without prior notice.
In addition, if we are not able to satisfy the requirements under customer trials or contracts with acceptance periods, we may be required to accept product returns from our customers, which would prevent us from recognizing revenue on such transactions and may result in the write-down of inventory. 56 We believe that cloud computing represents a fundamental shift from traditional legacy network architectures.
In addition, if we are not able to satisfy the requirements under customer trials or contracts with acceptance periods, we may be required to accept product returns from our customers, which would prevent us from recognizing revenue on such transactions and may result in the write-down of inventory.
Leases We have operating lease arrangements for office space, data center, equipment and other corporate assets. As of December 31, 2024, we had lease payment obligations, net of immaterial sublease income, of $65.3 million, with $24.7 million payable within 12 months.
Leases We have operating lease arrangements for office space, data center, equipment and other corporate assets. As of December 31, 2025, we had lease payment obligations, net of immaterial sublease income of $90.5 million, with $22.1 million payable within 12 months.
Inventory Valuation and Contract Manufacturer/Supplier Liabilities Inventories primarily consist of finished goods, including evaluation inventory held at customers or partners, and strategic components, primarily integrated circuits. Inventories are stated at the lower of cost (computed using the first-in, first-out method) and net realizable value.
Inventory Valuation and Supplier Liabilities Inventories primarily consist of finished goods, including evaluation inventory held at customers or partners, and strategic components, primarily integrated circuits. Inventories are stated at the lower of cost or net realizable value. Cost is computed using standard cost, which approximates actual cost, on a first-in, first-out basis.
In addition, although the focus on deployment of AI enabled solutions has driven increased demand for networking, the long-term trajectory is unknown. As such, demand estimates for our new products are difficult to forecast and can create volatility in our revenue.
In addition, although the focus on deployment of AI-enabled solutions has driven increased demand for networking, the long-term trajectory is unknown. As such, demand estimates for our new products are difficult to forecast and can create volatility in our revenue. We remain in a period of new product introductions and expanded use cases, particularly in the AI Ethernet market.
Net non-cash adjustments primarily consisted of an increase in deferred income taxes of $370.8 million primarily resulting from increased deferred tax assets associated with the capitalization of research and development costs under IRC Section 174, which were largely offset by $296.8 million of stock-based compensation expenses and $70.6 million of depreciation, amortization and other expenses.
Net non-cash adjustments primarily consisted of an increase in deferred income taxes of $492.9 million primarily resulting from increased deferred tax assets associated with the increase in deferred revenue and capitalization of research and development costs under IRC Section 174, which were largely offset by $355.4 million of stock-based compensation expenses.
Macroeconomic Update Global economic and business activities continue to face widespread macroeconomic uncertainties, including the effects of, among other things, inflation, monetary policy shifts, recession risks, potential supply chain disruptions, changes in the U.S. administration, geopolitical pressures and escalating international trade measures. Our business is emerging from a period of unprecedented global supply chain disruptions.
Macroeconomic Update Global economic and business activities continue to face widespread macroeconomic uncertainties, including the effects of, among other things, inflation, monetary policy shifts, recession risks, potential supply chain disruptions, changes in government administration policy positions, and geopolitical pressures, including escalating international trade measures and tariff uncertainty.
We record a liability and a corresponding charge for non-cancellable, non-returnable purchase commitments with our contract manufacturers and suppliers for quantities in excess of our demand forecasts or that are considered obsolete due to manufacturing and engineering change orders resulting from design changes. We use significant judgment in establishing our forecasts of future demand and obsolete material exposures.
We record a liability and a corresponding charge for non-cancellable, non-returnable purchase commitments with our suppliers for quantities in excess of our demand forecasts or that are considered obsolete. We use significant judgment in establishing our forecasts of future demand and obsolete material exposures.
Product revenue increased by $854.5 million, or 17.0%, for the year ended December 31, 2024 compared to 2023. This increase reflects healthy customer demand and higher shipments of our switching and routing platforms, with strong contributions across our customer base .
Product revenue increased by $1.7 billion, or 28.8%, for the year ended December 31, 2025 compared to 2024. This increase reflects healthy customer demand and higher shipments of our switching and routing platforms, with strong contributions across our customer base .
In addition, service revenue increased by $165.4 million, or 24.9%, in the year ended December 31, 2023 compared to 2022, as a result of continued growth in initial and renewal support contracts as our customer installed base has continued to expand.
In addition, service revenue increased by $309.7 million, or 27.7%, for the year ended December 31, 2025 compared to 2024, as a result of continued growth in initial and renewal support contracts as our customer installed base has continued to expand.
Other Income, Net (in thousands, except percentages) Other income (expense), net consists primarily of interest income from our cash, cash equivalents and marketable securities, and gains and losses on our strategic investments.
Other Income, Net (in millions, except percentages) Other income (expense), net consists primarily of interest income from our cash, cash equivalents and marketable securities.
Year Ended December 31, 2024 2023 Change in $ % of Revenue $ % of Revenue $ % Other income (expense), net: Interest income $ 310,998 4.4 % $ 152,421 2.6 % $ 158,577 104.0 % Other income (expense), net 9,420 0.1 12,356 0.2 (2,936) (23.8) Total other income, net $ 320,418 4.6 % $ 164,777 2.8 % $ 155,641 94.5 % The favorable movement in other income (expense), net, during the year ended December 31, 2024 as compared to 2023 was driven by an increase in interest income of $158.6 million due to an increase in our cash and marketable securities balances, coupled with higher investment yields.
General and administrative General and administrative expenses increased by $3.6 million, or 3.0%, for the year ended December 31, 2024 compared to 2023. 57 Other Income, Net (in millions, except percentages) Year Ended December 31, 2024 2023 Change in $ % of Revenue $ % of Revenue $ % Other income, net: Interest income $ 311.0 4.5 % $ 152.4 2.6 % $ 158.6 104.0 % Other income (expense), net 9.5 0.1 12.3 0.2 (2.8) (23.8) Total other income, net $ 320.5 4.6 % $ 164.7 2.8 % $ 155.8 94.5 % The favorable movement in other income (expense), net, during the year ended December 31, 2024 as compared to 2023 was driven by an increase in interest income of $158.6 million due to an increase in our cash and marketable securities balances, coupled with higher investment yields.
Our cash, cash equivalents and marketable securities are held for general business purposes, including the funding of working capital. Our marketable securities investment portfolio is primarily invested in highly-rated securities, with the primary objective of minimizing the potential risk of principal loss. We plan to continue to invest for long-term growth.
Our marketable securities investment portfolio is primarily invested in highly-rated securities, with the primary objective of minimizing the potential risk of principal loss. We plan to continue to invest for long-term growth.
For example, sales to our end customer Microsoft represented 20%, 18% and 16% of our total revenue for the years ended 2024, 2023 and 2022 respectively. And sales to our end customer Meta Platforms represented 15%, 21% and 26% of our total revenue, respectively for the years ended 2024, 2023 and 2022.
Sales to one end customer represented 16%, 15%, and 21% of our total revenue, and sales to the other end customer represented 26%, 20%, and 18% of our total revenue for the years ended December 31, 2025, 2024, and 2023, respectively.
The largest component of our operating expenses is personnel costs. Personnel costs consist of wages, benefits, bonuses and, with respect to sales and marketing expenses, sales commissions. Personnel costs also include stock-based compensation and travel-related expenses.
The largest component of our operating expenses is personnel costs and new product introduction costs. Personnel costs consist of wages, benefits, bonuses and, with respect to sales and marketing expenses, sales incentive compensation. Personnel costs also include stock-based compensation and travel-related expenses. New product introduction costs are primarily comprised of third-party engineering and prototype expenses.
Research and development expenses increased by $141.8 million, or 16.6%, for the year ended December 31, 2024 compared to 2023.
Research and development expenses increased by $240.6 million, or 24.1%, for the year ended December 31, 2025 compared to 2024.
The increase was primarily due to a $84.1 million increase in personnel costs driven by an increase in headcount, and a $40.7 million increase in new product introduction costs, including non-recurring engineering costs and prototype expenses as we expand our product portfolio.
The increase was primarily due to a $95.6 million increase in personnel costs driven by an increase in headcount, and a $78.6 million increase in new product introduction costs, including third-party engineering costs and prototype expenses as we expand our product portfolio. Sales and marketing.
In addition, we typically provide pricing discounts to large customers, which reduces gross margins for the period in which such sales occur. We believe an increased focus on the deployment of AI enabled solutions by our large customers has accelerated the need for advanced technology offerings including some offerings from potential new market entrants.
We believe an increased focus on the deployment of AI-enabled solutions by our large customers has accelerated the need for advanced technology offerings, including some offerings from potential new market entrants.
If we require or elect to seek additional capital through debt or equity financing in the future, we may not be able to raise capital on terms acceptable to us or at all. If we are required and unable to raise additional capital when desired, our business, operating results and financial condition may be adversely affected.
If we require or elect to seek additional capital through debt or equity financing in the future, we may not be able to raise capital on terms acceptable to us or at all.
We expect our sales and marketing expenses to increase in absolute dollars as we continue to expand our sales and marketing efforts worldwide. 59 Sales and marketing expenses increased by $28.2 million, or 7.1%, for the year ended December 31, 2024 compared to 2023 primarily due to an increase in personnel costs. General and administrative.
Sales and marketing Sales and marketing expenses increased by $28.3 million, or 7.1%, for the year ended December 31, 2024 compared to 2023 primarily due to an increase in personnel costs.
Results of Operations Year Ended December 31, 2024 Compared to Year Ended December 31, 2023 Revenue, Cost of Revenue and Gross Margin (in thousands, except percentages) Year Ended December 31, 2024 2023 Change in $ % of Revenue $ % of Revenue $ % Revenue Product $ 5,884,021 84.0 % $ 5,029,493 85.8 % $ 854,528 17.0 % Service 1,119,125 16.0 830,675 14.2 288,450 34.7 Total revenue 7,003,146 100.0 5,860,168 100.0 1,142,978 19.5 Cost of revenue Product 2,299,063 32.8 2,061,167 35.2 237,896 11.5 Service 212,780 3.1 168,720 2.9 44,060 26.1 Total cost of revenue 2,511,843 35.9 2,229,887 38.1 281,956 12.6 Gross profit $ 4,491,303 64.1 % $ 3,630,281 61.9 % $ 861,022 23.7 % Gross margin 64.1 % 61.9 % Revenue by Geography (in thousands, except percentages) Year Ended December 31, 2024 % of Total 2023 % of Total Americas $ 5,729,039 81.8 % $ 4,651,193 79.4 % Europe, Middle East and Africa 713,175 10.2 670,960 11.4 Asia-Pacific 560,932 8.0 538,015 9.2 Total revenue $ 7,003,146 100.0 % $ 5,860,168 100.0 % Revenue Product revenue primarily consists of sales of our switching and routing products, and related network applications.
Year Ended December 31, 2024 Compared to Year Ended December 31, 2023 Revenue, Cost of Revenue and Gross Margin (in millions, except percentages) Year Ended December 31, 2024 2023 Change in $ % of Revenue $ % of Revenue $ % Revenue Product $ 5,884.0 84.0 % $ 5,029.5 85.8 % $ 854.5 17.0 % Service 1,119.1 16.0 830.7 14.2 288.4 34.7 Total revenue 7,003.1 100.0 5,860.2 100.0 1,142.9 19.5 Cost of revenue Product 2,299.0 32.8 2,061.2 35.2 237.8 11.5 Service 212.8 3.1 168.7 2.9 44.1 26.1 Total cost of revenue 2,511.8 35.9 2,229.9 38.1 281.9 12.6 Gross profit $ 4,491.3 64.1 % $ 3,630.3 61.9 % $ 861.0 23.7 % Gross margin 64.1 % 61.9 % 56 Revenue by Geography (in millions, except percentages) Year Ended December 31, 2024 % of Total 2023 % of Total Americas $ 5,729.0 81.8 % $ 4,651.2 79.3 % Europe, Middle East and Africa 713.2 10.2 671.0 11.5 Asia-Pacific 560.9 8.0 538.0 9.2 Total revenue $ 7,003.1 100.0 % $ 5,860.2 100.0 % Revenue Product revenue increased by $854.5 million, or 17.0%, for the year ended December 31, 2024 compared to 2023.
Year Ended December 31, 2024 2023 Change in $ % of Revenue $ % of Revenue $ % Operating expenses: Research and development $ 996,717 14.2 % $ 854,918 14.6 % $ 141,799 16.6 % Sales and marketing 427,264 6.1 399,034 6.8 28,230 7.1 General and administrative 122,706 1.8 119,080 2.0 3,626 3.0 Total operating expenses $ 1,546,687 22.1 % $ 1,373,032 23.4 % $ 173,655 12.6 % Research and development.
Operating Expenses (in millions, except percentages) Year Ended December 31, 2024 2023 Change in $ % of Revenue $ % of Revenue $ % Operating expenses: Research and development $ 996.7 14.2 % $ 854.9 14.6 % $ 141.8 16.6 % Sales and marketing 427.3 6.1 399.0 6.8 28.3 7.1 General and administrative 122.7 1.8 119.1 2.0 3.6 3.0 Total operating expenses $ 1,546.7 22.1 % $ 1,373.0 23.4 % $ 173.7 12.7 % Research and development Research and development expenses increased by $141.8 million, or 16.6%, for the year ended December 31, 2024 compared to 2023.
The estimated capital expenditures related to this project is expected to be approximately $235.0 million to $260.0 million for the next two years, with construction expected to be completed by the end of fiscal 2026.
The estimated capital expenditures related to this project is expected to be approximately $170.0 million to $195.0 million through the end of fiscal 2026 when construction is expected to be completed.
In addition, w e expect that our inventory and purchase commitments will remain volatile as we ramp new product introductions. There is however no guarantee that all suppliers will meet their commitments in the time frame committed or that actual customer demand will directly match our demand forecasts.
There is, however, no guarantee that all suppliers will meet their commitments in the time frame committed or that actual customer demand will directly match our demand forecasts.
Stock Repurchase Programs From time to time, we repurchase shares of our common stock pursuant to the Repurchase Programs that are funded from working capital. In April 2024, we completed repurchases under our previous $1.0 billion stock repurchase program (“Prior Repurchase Program”).
Stock Repurchase Programs From time to time, we repurchase shares of our common stock pursuant to repurchase programs that are funded from working capital. In May 2025, we completed repurchases under the $1.2 billion Prior Repurchase Program, and our board of directors authorized the $1.5 billion New Repurchase Program.
Cost of service revenue primarily consists of 58 personnel and other costs associated with our global customer support and services organizations. Cost of revenue increased by $282.0 million, or 12.6% for the year ended December 31, 2024 compared to 2023.
Cost of service revenue primarily consists of personnel and other costs associated with our global customer support and services organizations. Cost of revenue increased by $725.2 million, or 28.9% for the year ended December 31, 2025 compared to 2024. These increases were driven by a corresponding increase in product and service revenues.
Sales and marketing expenses consist primarily of personnel costs, marketing, trade shows, and other promotional activities, and an allocated portion of facility and IT costs.
Sales and marketing expenses consist primarily of personnel costs, marketing, trade shows, and other promotional activities, and an allocated portion of facility and IT costs. We expect our sales and marketing expenses to increase in absolute dollars as we continue to expand our sales and marketing efforts worldwide.
General and administrative expenses consist primarily of personnel costs and professional services costs for our finance, human resources, legal and certain executive functions. Our professional services costs are primarily related to external legal, accounting, and tax services. General and administrative expenses increased by $3.6 million, or 3.0%, for the year ended December 31, 2024 compared to 2023.
Sales and marketing expenses increased by $106.1 million, or 24.8%, for the year ended December 31, 2025 compared to 2024 primarily due to an increase in personnel costs driven by an increase in headcount. General and administrative. General and administrative expenses consist primarily of personnel costs and professional services costs for our finance, human resources, legal and certain executive functions.
Liquidity and Capital Resources Our principal sources of liquidity are cash, cash equivalents, marketable securities, and cash generated from operations. As of December 31, 2024, our total balance of cash, cash equivalents and marketable securities was $8.3 billion, of which approximately $1.4 billion was held outside the U.S. in our foreign subsidiaries.
As of December 31, 2025, our total balance of cash, cash equivalents and marketable securities was $10.7 billion, of which approximately $1.0 billion was held outside the U.S. in our foreign subsidiaries. Our cash, cash equivalents and marketable securities are held for general business purposes, including the funding of working capital.
During the year ended December 31, 2023, cash used in investing activities was $687.5 million, consisting of purchases of available-for-sale securities of $2.6 billion, and purchases of property, equipment and intangible assets of $34.4 million, partially offset by proceeds of $1.9 billion from maturities of marketable securities, and proceeds from the sale of marketable securities of $67.3 million, Cash Flows from Financing Activities Our financing activities consist of proceeds from the issuance of our common stock under employee equity incentive plans, offset by repurchases of our common stock.
During the year ended December 31, 2025, cash used in investing activities was $3.6 billion, consisting of purchases of available-for-sale securities of $6.7 billion, $300.0 million for the business acquisition of VeloCloud. and purchases of property, equipment and intangible assets of $119.5 million, partially offset by proceeds of $3.6 billion from maturities and sales of marketable securities.
For further information regarding income taxes and the impact on our results of operations and financial position, refer to Note 8. Income Taxes of the Notes to Consolidated Financial Statements included in Part II, Item 8, of this Annual Report on Form 10-K.
Income Taxes of the Notes to Consolidated Financial Statements included in Part II, Item 8, of this Annual Report on Form 10-K. Liquidity and Capital Resources Our principal sources of liquidity are cash, cash equivalents, marketable securities, and cash generated from operations.
Service revenue is primarily derived from sales of PCS contracts, which are typically purchased in conjunction with our products, and subsequent renewals of those contracts. We expect our revenue may vary from period to period based on, among other things, the timing, size, and complexity of orders, especially with respect to our large customers.
Service revenue is primarily derived from sales of PCS contracts, which are typically purchased in conjunction with our products, and subsequent renewals of those contracts.
In addition, although the global supply chain has shown improvement, we have had to invest in inventory to address forecast uncertainty and expect that our inventory and purchase commitments will remain volatile as we ramp new product introductions.
In addition, although the global supply chain has shown improvement, we have had to invest in inventory and increase our purchase commitments to address forecast uncertainty and we anticipate continued volatility in our inventory and purchase commitments. This variability is driven by new product introductions, fluctuating customer demand and varying supplier lead times.
Our future success is dependent upon our ability to continue to evolve and adapt to our rapidly changing environment. We must also continue to develop market-leading products and software features that address the changing needs of our existing and new customers, and increase sales in the cloud, AI and enterprise data center ethernet switching/routing markets, and campus workspace markets.
The market for cloud networking is characterized by rapid technological evolution, intensifying competition, and the expansion of generative and agentic AI. To sustain our success and adapt to the market, we must increase sales in cloud, AI and enterprise data center Ethernet switching/routing markets, and campus workspace markets by leveraging our ability to rapidly develop new features and software applications.
Net non-cash adjustments primarily consisted of an increase in deferred income taxes of $492.9 million primarily resulting from increased deferred tax assets associated with the increase in deferred revenue and capitalization of research and development costs under IRC Section 174, which were largely offset by $355.4 million of stock-based compensation expenses. 63 During the year ended December 31, 2023, cash provided by operating activities was $2.0 billion, primarily from net income of $2.1 billion, offset by net non-cash adjustments to net income of $37.4 million, and a net change of $15.9 million in working capital requirements.
Net non-cash adjustments primarily consisted of $439.2 million of stock-based compensation expenses, which was largely offset by an increase in deferred income taxes of $312.0 million primarily resulting from increased deferred tax assets associated with the increase in deferred revenue.
Cash Flows Year Ended December 31, 2024 2023 2022 (in thousands) Cash provided by operating activities $ 3,708,235 $ 2,034,014 $ 492,813 Cash provided by (used in) investing activities (2,457,354) (687,454) 216,327 Cash (used in) financing activities (421,810) (83,749) (654,601) Effect of exchange rate changes (4,767) 675 (3,611) Net increase in cash, cash equivalents and restricted cash $ 824,304 $ 1,263,486 $ 50,928 Cash Flows from Operating Activities Our operating activities consist of net income, adjusted for certain non-cash items, and changes in operating assets and liabilities.
If we are required and unable to raise additional capital when desired, our business, operating results and financial condition may be adversely affected. 58 Cash Flows Year Ended December 31, 2025 2024 2023 (in millions) Cash provided by operating activities $ 4,371.9 $ 3,708.2 $ 2,034.0 Cash (used in) investing activities (3,576.2) (2,457.3) (687.5) Cash (used in) financing activities (1,595.9) (421.8) (83.8) Effect of exchange rate changes 1.7 (4.8) 0.8 Net increase in cash, cash equivalents and restricted cash $ (798.5) $ 824.3 $ 1,263.5 Cash Flows from Operating Activities Our operating activities consist of net income, adjusted for certain non-cash items, and changes in operating assets and liabilities.
General and administrative General and administrative expenses increased by $25.8 million, or 27.7%, for the year ended December 31, 2023 compared to 2022. The increase was primarily caused by an increase in personnel costs driven by increased stock-based compensation, and increased legal and professional fees.
Our professional services costs are primarily related to external legal, accounting, and tax services. General and administrative expenses increased by $19.2 million, or 15.6%, for the year ended December 31, 2025 compared to 2024 primarily due to an increase in professional fees.
The change in working capital requirements primarily consisted of a $655.5 million increase in inventory in response to a significant increase in business volume, a $101.5 million increase in accounts receivable due to the larger business volume and timing of shipments in the fourth quarter of 2023, as well as a $66.4 million increase in other assets primarily driven by increased deferred cost of sales associated with higher product revenue deferrals.
These cash inflows were partially offset by a $412.5 million increase in inventory in response to an increase in business volume, a $937.4 million increase in other assets driven by increased deferred cost of goods sold associated with higher product revenue deferrals, and an increase in accounts receivable of $746.4 million due to increased product and service billings.
We expect our gross margin to fluctuate over time, depending on the factors described above. Gross margin increased from 61.9% for the year ended December 31, 2023 to 64.1% for the year ended December 31, 2024.
We expect our gross margin to fluctuate over time, depending on the factors described above. Gross margin remained constant at 64.1% for the years ended December 31, 2025 and 2024. Operating Expenses (in millions, except percentages) Our operating expenses consist of research and development, sales and marketing, and general and administrative expenses.
Other Income, Net (in thousands, except percentages) Year Ended December 31, 2023 2022 Change in $ % of Revenue $ % of Revenue $ % Other income, net: Interest income $ 152,421 2.6 % $ 27,556 0.6 % $ 124,865 453.1 % Other income (expense), net 12,356 0.2 27,134 0.6 (14,778) (54.5) Total other income, net $ 164,777 2.8 % $ 54,690 1.2 % $ 110,087 201.3 % The favorable movement in other income (expense), net, during the year ended December 31, 2023 as compared to 2022 was driven by an increase in interest income of $124.9 million due to an increase in our cash and investments balances and higher interest rates.
We expect other income (expense), net may fluctuate in the future as a result of changes in interest rates, changes in our cash, cash equivalents and marketable securities balances. 55 Year Ended December 31, 2025 2024 Change in $ % of Revenue $ % of Revenue $ % Other income (expense), net: Interest income $ 383.4 4.3 % $ 311.0 4.4 % $ 72.4 23.3 % Other income (expense), net 10.2 0.1 9.5 0.1 0.7 7.4 Total other income, net $ 393.6 4.4 % $ 320.5 4.6 % $ 73.1 22.8 % The favorable movement in other income (expense), net, during the year ended December 31, 2025 as compared to 2024 was driven by an increase in interest income of $72.4 million due to an increase in our cash and marketable securities balances.
We have experienced unpredictability in the timing of orders from these large customers primarily due to the time it takes these customers to evaluate, test, qualify and accept our newer products, the overall complexity of these large orders and changes in demand patterns specific to these customers, including reductions in or changes in mix of capital expenditures by these customers and the impact of cost reduction and other efficiency efforts by these customers.
We have experienced unpredictability in the timing of orders from our high-volume customers, primarily due to the inherent complexity of large-scale orders and fluctuations in their specific demand. This includes reductions or shifts in their capital expenditure budgets, as well as the impact of their internal cost-reduction and efficiency initiatives.
The percentage of revenue derived from these product categories during the current fiscal year was approximately 65% from Core, 18% from Cognitive Adjacencies, and 17% from Networking software and services. Our customers include companies of all sizes and span a range of industries and geographies and are grouped into the following categories: Cloud and AI Titans, Enterprise and Providers.
The percentage of revenue derived from these product categories during the current fiscal year was approximately 65% from Core, 18% from Cognitive Adjacencies, and 17% from Software and Services. With world-class engineering expertise and platform innovation, our customers gain the predictable performance and operational simplicity required to turn data into a sustainable competitive advantage in a modern, AI-driven world.
These cash outflows were largely offset by a $465.0 million increase in deferred revenue driven by a growth in PCS contracts and increased product deferred revenue related to customer contracts with acceptance terms, a $322.3 million increase in accounts payable and other liabilities related to significant business volume, timing of payments, and increased supplier and contract manufacturer liability reserves and a $20.2 million increase in income taxes, net, due to timing of payments.
Operating cash inflows consisted of an increase in deferred revenue of $2.5 billion resulting from an increase in product deferred revenue related to customer contracts with acceptance terms and increased customer PCS contracts, and a $379.9 million increase in accounts payable and other liabilities related to growing business volume and timing of payments to our large vendors.
These estimates depend on our assessment of current and expected orders from our customers, product development plans and current sales levels. In addition, industry-wide supply chain shortages in prior years have resulted in extended lead times for some 66 components, and consequently we were required to extend the time horizon of our demand forecasts.
These estimates depend on our assessment of current and expected orders from our customers, product development plans and current sales levels. Despite general improvements in the supply environment, fluctuations in supplier lead times and the persistence of some long-lead components require us to maintain elevated inventory levels and purchase commitments.
International revenues as a percentage of our total revenues decreased from 21.0% in 2022 to 20.6% in 2023, which was primarily driven by changes in the geographic mix of sales to our large global customers. Cost of Revenue and Gross Margin Cost of revenue increased by $524.3 million, or 30.7% for the year ended December 31, 2023 compared to 2022.
Cost of Revenue and Gross Margin Cost of revenue increased by $282.0 million, or 12.6% for the year ended December 31, 2024 compared to 2023.
The percentage of revenue derived from these customers during the current fiscal year was approximately 48% from Cloud and AI Titans, 35% from Enterprise and 17% from Providers. Historically, large purchases by a relatively limited number of customers have accounted for a significant portion of our revenue.
The percentage of revenue derived from these customers during the current fiscal year was approximately 48% from Cloud and AI Titans, 32% from Enterprise and 20% from AI and Specialty Providers. Arista established itself as a market leader with platforms, products, and people to enable some of these hyperscalers’ most consequential networks.
Increased capacity has allowed us to ship products against previously committed demand/deployment plans and accelerate some deployments where needed, while trying to balance our customers' requirements and lead times with the availability of key components and products and lead times of our key suppliers and contract manufacturers.
Simultaneously, we are balancing customers’ requirements and lead times against the availability and lead times of key components and products from our suppliers and contract manufacturers.
During the year ended December 31, 2023, cash used in financing activities was $83.7 million, consisting primarily of common stock repurchases of $112.3 million and taxes paid of $33.6 million upon vesting of restricted stock units, offset partially by proceeds from the issuance of common stock under employee equity incentive plans of $62.1 million.
During the year ended December 31, 2025, cash used in financing activities was $1.6 billion, consisting of payments for repurchases of our common stock from the open market of $1.6 billion.
In addition, we intend to continue to invest in our research and development organization to enhance the functionality of our existing cloud networking platform, introduce new products and features, and build upon our technology leadership. We believe one of our greatest strengths lies in our ability to rapidly develop new features and applications.
Our growth strategy relies on maintaining our agility and increasing our investment in research and development to deliver market-leading features to enhance the functionality of our existing cloud networking platform, expand our product offerings and build upon our technology leadership.
Furthermore, any prolonged economic disruptions or further deterioration in the global economy could have a negative impact on demand from our customers in future periods, particularly in the enterprise market where we are continuing to expand our penetration. Accordingly, current results and financial conditions discussed herein may not be indicative of future operating results and trends.
Additionally, broader macroeconomic instability could negatively affect demand, particularly within the enterprise market. Given these unpredictable factors, current financial conditions discussed herein may not be indicative of future operating results and trends.