Table of Contents Gross profit may vary from quarter to quarter and is primarily affected by our ASPs, product cost, product mix, customer mix, AMPTC, shipping costs, warranty costs and sales volume fluctuations resulting from seasonality. Operating Expenses Operating expenses consist of research and development, sales and marketing, general and administrative and restructuring and asset impairment charges. Personnel-related costs are the most significant component of each of these expense categories, other than restructuring and asset impairment charges, and include salaries, benefits, payroll taxes, sales commissions, incentive compensation, post-combination expense and stock-based compensation. Research and development expense includes personnel-related expenses, third-party design and development costs, testing and evaluation costs, depreciation expense and other indirect costs. Research and development employees are primarily engaged in the design and development of power electronics, semiconductors, powerline communications, networking and software functionality, and storage. We devote substantial resources to research and development programs that focus on enhancements to, and cost efficiencies in, our existing products and timely development of new products that utilize technological innovation to drive down product costs, improve functionality, and enhance reliability. We intend to continue to invest appropriate resources in our research and development efforts because we believe they are critical to maintaining our competitive position. Sales and marketing expense includes personnel-related expenses, travel, trade shows, marketing, customer support and other indirect costs. We expect to continue to make the necessary investments to enable us to execute our strategy to increase our market penetration geographically and enter into new markets by expanding our customer base of distributors, large installers, OEMs and strategic partners. We currently offer solutions targeting the residential and commercial markets in the United States, Canada, Mexico, Europe, Australia, New Zealand, India, Brazil, the Philippines, Thailand, South Africa and certain other Central American and Asian markets. We expect to continue to expand the geographic reach of our product offerings and explore new sales channels in addressable markets in the future. General and administrative expense includes personnel-related expenses for our executive, finance, human resources, information technology and legal organizations, facilities costs, and fees for professional services. Fees for professional services consist primarily of outside legal, accounting and information technology consulting costs. Restructuring and asset impairment charges are the net charges resulting from restructuring initiatives implemented in 2022 and 2023 to increase operational efficiencies and execution, reduce operating costs, and better align our workforce and cost structure with current market conditions, as well as reflect our business needs, strategic priorities and ongoing commitment to profitable growth. Under the 2023 Restructuring Plan, costs included in restructuring and asset impairment charges primarily consisted of employee severance and one-time benefits, workforce reorganization charges and asset impairment charges. Refer to Note 12. “Restructuring and Asset Impairment Charges,” of the notes to consolidated financial statements included in Part II, Item 8 of this Annual Report on Form 10-K for additional information. Other Income (Expense), Net Other income (expense), net primarily consists of interest income on our cash, cash equivalents and marketable securities, amortization of discount or premium on purchase of cash equivalents and marketable securities, gains or losses upon conversion of foreign currency transactions into U.S. dollars, interest expense, changes in fair value of contingent consideration, non-cash interest expense related to the accretion of debt discount and amortization of deferred financing costs, non-cash charges recognized for loss on partial settlement of convertible notes, and the change in fair value of our debt securities. Income Tax Benefit (Provision) We are subject to income taxes in the countries where we sell our products. Historically, we have primarily been subject to taxation in the United States because we have sold the majority of our products to customers in the United States. As we have expanded the sale of products to customers outside the United States, we have become subject to taxation based on the foreign statutory rates in the countries where these sales took place. As sales in foreign jurisdictions increase in the future, our effective tax rate may fluctuate accordingly. We regularly assess the ability to realize deferred tax assets based on the weight of all available evidence, including such factors as the history of recent earnings and expected future taxable income on a jurisdiction by jurisdiction basis. Enphase Energy, Inc. | 2023 Form 10-K | 51