Table of Contents ENPHASE ENERGY, INC. NOTES TO CONSOLIDATED FINANCIAL STATEMENTS Stock-based Compensation Expense Stock-based compensation expense for all stock-based awards, which includes shares purchased under the ESPP, RSUs and PSUs, expected to vest is measured at fair value on the date of grant and recognized ratably over the requisite service period. In addition, as part of certain business acquisitions, the Company was obligated to issue shares of common stock of the Company as payment subject to achievement of certain targets. For such payments, the Company records stock-based compensation classified as post-combination expense recognized ratably over the measurement period presuming the targets will be met. The following table summarizes the components of total stock-based compensation expense included in the consolidated statements of operations for the periods presented: Years Ended December 31, 2023 2022 2021 (In thousands) Cost of revenues $ 13,357 $ 13,097 $ 7,366 Research and development 88,367 69,082 33,927 Sales and marketing 65,703 78,819 37,434 General and administrative 45,430 55,804 35,559 Total $ 212,857 $ 216,802 $ 114,286 Income tax benefit included in the provision for income taxes $ 20,558 $ 45,066 $ 97,129 The following table summarizes the various types of stock-based compensation expense for the periods presented: Years Ended December 31, 2023 2022 2021 (In thousands) Stock options, RSUs and PSUs $ 204,238 $ 200,295 $ 110,142 Employee stock purchase plan 7,450 5,475 4,144 Post combination expense 1,169 11,032 — Total $ 212,857 $ 216,802 $ 114,286 As of December 31, 2023, there was approximately $384.3 million of total unrecognized stock-based compensation expense related to unvested equity awards, which are expected to be recognized over a weighted- average period of 2.6 years. Enphase Energy, Inc. | 2023 Form 10-K | 113