8. Stock-Based Compensation

2019 Stock Incentive Plan

The 2019 Stock Incentive Plan (the “2019 Plan”) provides for the grant of incentive stock options, nonqualified stock options, stock appreciation rights, restricted stock, restricted stock units (“RSUs”), unrestricted stock, unrestricted stock units, and other stock-based awards to employees, directors, and consultants of the Company and its subsidiaries. The number of shares of common stock of TransMedics Group initially available for issuance under the 2019 Plan was 3,428,571 shares, which was increased by 1,000,000 shares in 2023, plus the number of shares underlying awards under the previously outstanding 2014 Stock Incentive Plan (the “2014 Plan”), not to exceed 1,595,189 shares, that expire or are terminated, surrendered, or cancelled without the delivery of shares, are forfeited to or repurchased by TransMedics Group or otherwise

become available again for grant. Since the effectiveness of the Company’s 2019 Plan in April 2019, no awards have been made or will be made under the 2014 Plan.

Shares withheld in payment of the exercise or purchase price of an award or in satisfaction of tax withholding requirements, and the shares covered by a stock appreciation right for which any portion is settled in stock, will reduce the number of shares available for issuance under the 2019 Plan. In addition, the number of shares available for issuance under the 2019 Plan (i) will not be increased by any shares delivered under the 2019 Plan that are subsequently repurchased using proceeds directly attributable to stock option exercises and (ii) will not be reduced by any awards that are settled in cash or that expire, become unexercisable, terminate or are forfeited to or repurchased by TransMedics Group without the issuance of stock under the 2019 Plan. On May 20, 2026, the shareholders of the Company approved an amendment to the Amended and Restated 2019 Stock Incentive Plan (the “Amended 2019 Plan”) to among other things, (i) increase the number of shares of the Company’s common stock available for issuance thereunder by 2,750,000 shares, (ii) extend the term of the Amended 2019 Plan until June 1, 2036, (iii) provide that, for awards granted on or after January 1, 2027, no portion of an award may be scheduled to vest prior to the date that is one year following the date the award is granted, except for awards that result in the issuance of an aggregate of up to five percent of the shares authorized under the Amended 2019 Plan and (iv) provide for “double-trigger” vesting of awards following a change in control. As of June 30, 2026, 3,177,228 shares of common stock were available for issuance under the Amended 2019 Plan.

2021 Inducement Plan

In August 2021, the Company’s board of directors approved the TransMedics Group, Inc. Inducement Plan (the “Inducement Plan”). Pursuant to the terms of the Inducement Plan, the Company may grant nonqualified stock options, stock appreciation rights, restricted stock, unrestricted stock, RSUs and performance awards to individuals who were not previously employees or directors of the Company or individuals returning to employment after a bona fide period of non-employment with the Company. A total of 1,000,000 shares of the Company’s common stock were initially available for issuance under the Inducement Plan, which was increased by 500,000 shares in 2023. As of June 30, 2026, 328,779 shares of common stock remained available for issuance under the Inducement Plan.

2019 Employee Stock Purchase Plan

Pursuant to the Company’s 2019 Employee Stock Purchase Plan (the “2019 ESPP”), certain employees of the Company are eligible to purchase common stock of the Company at a reduced price during offering periods. The 2019 ESPP permits participants to purchase common stock using funds contributed through payroll deductions, subject to the limitations set forth in the Internal Revenue Code, at a purchase price of 85% of the lower of the closing price of the Company’s common stock on the first trading day of the offering period or the closing price on the applicable purchase date, which is the final trading day of the applicable offering period. A total of 371,142 shares of TransMedics Group common stock were initially reserved for issuance under the 2019 ESPP. During the six months ended June 30, 2026, 16,321 shares of common stock were issued under the 2019 ESPP and as of June 30, 2026, 157,939 shares of common stock remained available for issuance under the 2019 ESPP.

Stock Option Activity

During the six months ended June 30, 2026, the Company granted options with service-based vesting for the purchase of an aggregate of 77,456 shares of common stock with a weighted average grant-date fair value of $67.42 per share.

Restricted Stock Unit Activity

During the six months ended June 30, 2026, the Company granted 71,851 RSUs with service-based vesting conditions and a weighted average grant-date fair value of $92.29 per share.

Stock-Based Compensation

As of June 30, 2026, total unrecognized compensation cost related to unvested share-based awards was $54.4 million, which is expected to be recognized over a weighted average period of 2.2 years.

The Company recognized income tax benefits related to stock-based compensation expense of $0.4 million and $4.2 million as a component in calculating its income taxes during the three and six months ended June 30, 2026, respectively. Income tax benefits related to stock-based compensation expense for the three and six months ended June 30, 2025 were fully offset by the valuation allowance against deferred tax assets.