12. Stockholders' Equity and Stock-Based Compensation

Equity Incentive Plan

On April 30, 2026, the Company’s stockholders approved the Amended and Restated 2026 Equity Incentive Plan (the “2026 Plan”) which amended and restated the 2015 Equity Incentive Plan to (i) increase the number of shares of common stock reserved for issuance thereunder by 2,000,000 shares, (ii) effect the name change of the 2026 Plan, (iii) change the provision regarding non-employee director compensation limits from a number of shares of common stock not to exceed 500,000 shares to total compensation of (a) no more than $1,250,000 in combined cash and equity awards during such director’s year of appointment and (b) no more than $750,000 in combined cash and equity awards in any other year of service, and (iv) remove and revise certain provisions that were otherwise required for awards to qualify as performance-based compensation under Section 162(m) of the Internal Revenue Code of 1986, as amended, prior to the repeal of the applicable limitations thereunder. The 2026 Plan is administered by the Board of Directors (the “Board”) and permits the granting of stock, stock options, stock appreciation rights, restricted stock, restricted stock units and dividend equivalent rights to employees, officers, directors and consultants of the Company. As of September 30, 2026, the aggregate shares of common stock reserved for issuance under the 2026 Plan, as amended, is 16,930,277 shares.

Common Stock Repurchases

On July 31, 2025, the Board authorized a program to repurchase up to $400.0 million of shares of the Company’s common stock through December 31, 2027 (the “2025 Program”). During the three and nine months ended September 30, 2026, the Company did not repurchase any of its common stock under the 2025 Program. During 2025, the Company repurchased a total of 3.5 million shares for an aggregate purchase price of approximately $200.0 million under the 2025 Program for an average stock price of $56.72. A total of approximately $200.0 million of shares of the Company’s common stock remain available for repurchase under the 2025 Program as of September 30, 2026.

Employee Stock Purchase Plan

Effective September 11, 2026, the Lantheus Holdings, Inc. 2023 Employee Stock Purchase Plan (the “2023 ESPP”) was suspended after the completion of the current offering period. The 2023 ESPP provided for the granting of up to 500,000 shares of the Company’s common stock to eligible employees. The 2023 ESPP allowed eligible employees to contribute up to 15% of their qualifying compensation toward the semi-annual purchase of the Company’s common stock in March and September of each year, subject to an annual maximum dollar amount. The purchase price was the lesser of 85% of the fair market value of the stock on the last trading day of each Offering Period (as defined in the 2023 ESPP); or the first trading day of each Offering Period. In March 2026 and September 2026, the Company issued 58,907 shares and 31,956 shares under the 2023 ESPP, respectively. As of September 30, 2026, the number of shares that would have been available for issuance under the 2023 ESPP if the suspension was not in place was 308,437 shares. The Company calculated the fair value of the shares issued under the 2023 ESPP using the Black-Scholes model at the commencement of an Offering Period in March and September of each year and the related expense is recorded over the Offering Period. Shares issuable under the Offering Period ending September 11, 2026 were issued in accordance with the 2023 ESPP, and no additional Offering Period commenced thereafter.

Stock-Based Compensation Expense