16. Stock-Based Compensation

atai Equity Incentive Plans

The Company has stock options and RSUs outstanding under various equity incentive plans, including the 2021 Incentive Plan, 2020 Incentive Plan, and HSOP Plan (all as defined below).

AtaiBeckley, Inc. 2021 Incentive Award Plan

Effective April 23, 2021, the Company originally adopted and the atai shareholders approved the 2021 Incentive Award Plan (“2021 Incentive Plan”). The 2021 Incentive Plan was again approved in connection with the Redomiciliation Transaction. The 2021 Incentive Plan is administered by the Company’s board. The 2021 Incentive Plan is intended to encourage ownership of shares by employees, directors, and certain consultants to the Company in order to attract and retain such individuals, to induce them to work for the benefit of the Company or of an affiliate and to provide additional incentive for them to promote the success of the Company. The 2021 Incentive Plan enables the Company to grant incentive stock options or nonqualified stock options, restricted stock awards and other stock-based awards to executive officers, directors and other employees and consultants of the Company.

The Company has reserved up to 71,734,896 shares of common stock for issuance to executive officers, directors and employees and consultants of the Company pursuant to the 2021 Incentive Plan. In accordance with the evergreen clause in the Company's 2021 Incentive Plan, the number of shares initially available for issuance was increased by 8,301,319 and 8,397,987 shares of common stock effective January 1, 2024 and 2025, respectively. Shares that are expired, terminated, surrendered, or canceled without having been fully exercised will be available for future awards. As of December 31, 2025, 31,145,683 shares were available for future grants under the 2021 Incentive Plan.

Atai Life Sciences 2020 Equity Incentive Plan

Prior to the effective date of the 2021 Incentive Plan, the Company granted equity awards to eligible executive officers, directors, employees and consultants of the Company under the 2020 Employee, Director and Consultant Equity Incentive Plan (as amended from time to time, “2020 Incentive Plan”). As of the effective date of the 2021 Incentive Plan, the Company has not granted any further awards under the 2020 Incentive Plan.

As of December 31, 2025, there were no shares available for future grants under the 2020 Incentive Plan and any shares subject to outstanding stock options originally granted under the 2020 Incentive Plan that terminate, expire or lapse for any reason without the delivery of shares to the holder thereof shall become available for issuance pursuant to the 2021 Incentive Plan.

In October 2024, the Company modified all outstanding pre-IPO stock options under the 2020 Incentive Plan to extend the contractual term to be ten years, to align with stock options granted under the 2021 Incentive Plan, which is consistent with prevailing market practices. The Company recognized approximately $3.2 million in non-cash stock-based compensation expense related to this modification, including $2.0 million of research and development expenses and $1.2 million of general and administrative expenses.

Stock Options

The stock options outstanding below consist primarily of both service and performance-based options to purchase common stock of the Company. These stock options have a ten-year contractual term. These awards are subject to the risk of forfeiture until vested by virtue of continued employment or service to the Company.

As described in Note 4, Acquisitions, the Company issued 1,546,258 vested stock options as replacement awards to certain consultants of Beckley Psytech and certain equity award holders in Beckley Psytech. The shares underlying the options issued as replacement awards are subject to a lock-up period whereby 1/12th of the shares will be released from the lock-up each calendar month beginning in January 2026, resulting in all shares subject to such options being freely transferable in January 2027. The Company did not recognize any expense related to the issuance of such replacement options.

The weighted-average grant-date fair value of options granted during the years ended December 31, 2025 and 2024 was $1.37 and $1.35, respectively.

For the years ended December 31, 2025 and 2024, the Company recorded stock-based compensation expense related to stock options of $13.7 million and $23.5 million, respectively.

As of December 31, 2025, total unrecognized compensation cost related to the unvested stock options was $22.8 million, which is expected to be recognized over a weighted average period of 2.15 years.

Restricted Stock Units

The Company has granted RSUs to certain of its employees under the 2021 Incentive Plan, as part of its equity compensation program. Pursuant to the terms of the applicable award agreements, each RSU represents the right to receive one share of the Company’s common stock. The restricted stock units noted below consist of service-based awards vesting over a two-year period, subject to the risk of forfeiture until vested by virtue of continued employment or service to the Company. The Company reflects restricted stock units as issued and outstanding common stock when vested and the shares have been delivered to the individual.

As described in Note 4, Acquisitions, the Company issued 6,971,912 fully vested RSUs as replacement awards to certain equity award holders in Beckley Psytech. The number of RSUs issued as replacement awards was determined net of the exercise price of the equivalent Beckley Psytech option awards to which they correspond. The shares underlying the RSUs are subject to a lock-up period whereby 1/12th of the shares will be released from the lock-up each calendar month beginning in January 2026, resulting in all shares being freely transferable in January 2027. As a result of the RSU issuance, the Company recognized an additional $0.3 million of stock-based compensation expense.

For the years ended December 31, 2025 and 2024, the Company recorded stock-based compensation expense related to restricted stock units of $0.5 million and $1.8 million, respectively. The total fair value of restricted stock units vested during the year ended December 31, 2025 was $0.8 million and there was no unrecognized compensation expense related to any unvested restricted stock units.

Atai Life Sciences Hurdle Share Option Plan

On August 21, 2020, the Partnership (as defined below) approved and implemented an employee stock option plan for selected executives, employees, and consultants of the Partnership (the "Hurdle Share Options Program" or the “HSOP Plan”), which became effective on

January 2, 2021, the date the first grants under the HSOP Plan were made (“HSOP Options”). This plan is primarily aimed at German-based executives, employees, and consultants of the Company (collectively as “HSOP Participants”). The purpose of the HSOP Plan is to permit these individuals to indirectly participate in the appreciation in value of the Company through a German law private partnership, ATAI Life Sciences HSOP GbR (the “Partnership”). The HSOP Plan was established under the Partnership Agreement of the Partnership. The HSOP Plan requires the exercise price to be equal to the fair value of the shares on the date of grant.

The Partnership acquired 7,281,376 shares of atai common stock (“HSOP Shares”) pursuant to the HSOP Plan. HSOP Options that are canceled or forfeited without having been fully exercised will be available for future awards. As of December 31, 2025, 257,419 HSOP Options were available for future grants under the HSOP Plan.

The HSOP Plan mimics the economics of a typical stock option plan, however, with the HSOP Shares to which the HSOP Options refer already being issued to the Partnership. Each HSOP Option contains both service and performance-based vesting conditions, including a liquidity-based condition, and gives the holder the option to request the distribution of HSOP Shares under its vested HSOP Options. The grantee is required to pay a nominal value (€0.06 per share) for the shares upon grant (“Nominal Upfront Payment”). The nominal amount paid at the grant date is refundable if the HSOP Options do not vest or are forfeited. Otherwise, the nominal amount is refundable until the later of the occurrence of a Liquidity Event (as defined in the “HSOP Plan”) or the exercise date.

The HSOP Shares issued under the HSOP Plan to the Partnership are indirectly owned by HSOP Participants (being the holders of HSOP Options) via their interest in the Partnership. However, each HSOP Participant signed a nonrevocable power of attorney ceding virtually all rights and decisions, including their rights as shareholders to the Managing Partner (as defined in the Partnership Agreement) of the Partnership. HSOP Participants have a forfeitable right to distributions until the HSOP Options vest, at which time the right becomes nonforfeitable. Accordingly, the HSOP Shares issued to the Partnership and allocated to the HSOP Options holders are not considered outstanding for accounting purposes. Therefore, the Company accounted for the Nominal Upfront Payment as an in-substance early exercise provision under ASC 718 as the nominal amount is deducted from the exercise price upon exercise. As of December 31, 2025, the $0.5 million Nominal Upfront Payment was recorded as an Other liability on the consolidated balance sheets. The HSOP Options include a provision that requires the HSOP Options holders pay compensation equal to 2% per annum interest on the unpaid exercise price less the €0.06 nominal amount paid upon grant (“Non-recourse Loan”) upon qualifying events (as defined in the Partnership Agreement).

The 2% per annum interest rate is fixed and not linked to something other than a service, performance, or market condition, therefore, the Company accounted for the fixed rate interest charge as an in-substance non-recourse loan in a stock compensation arrangement under ASC 718. In such cases, the rights and obligations embodied in a transfer of equity shares to an employee for a note that provides no recourse to other assets or the employee (other than the correlating shares) are substantially the same as those embodied in a grant of share options. The 2% per annum interest was considered in the valuation of the HSOP Options.

HSOP Options

The HSOP Options outstanding noted below consist of service and performance-based options to request the distribution of HSOP Shares. These HSOP Options have a fifteen-year contractual term. These HSOP Options vest over a three to four-year service period, only if and when a “Liquidity Event” (as defined in the Partnership Agreement) occurs within fifteen years of the date of grant. These awards are subject to the risk of forfeiture until vested by virtue of continued employment or service to the Company.

The liquidity-based performance condition contingent upon the achievement of a Liquidity Event was satisfied in June of 2021, therefore, the Company began recognizing expense for all associated options that were previously deemed improbable of vesting.

The Company estimates the fair values of stock options using the Black-Scholes option-pricing model on the date of grant. As shown above, the Company did not grant any new HSOP Options during the year ended December 31, 2025 or 2024. The Company did not recognize any stock-based compensation expense related to HSOP Options for the year ended December 31, 2025 and recognized expenses of $0.1 million related to HSOP Options for the year ended December 31, 2024.

As of December 31, 2025, there was no unrecognized compensation cost related to any unvested HSOP Options.

Subsidiary Equity Incentive Plans

Certain controlled subsidiaries of the Company adopt their own equity incentive plan (“EIP”). Each EIP is generally structured so that the applicable subsidiary, and its affiliates’ employees, directors, officers and consultants are eligible to receive non-qualified and incentive stock options and restricted stock unit awards under their respective EIP. Standard option grants have time-based vesting requirements, generally vesting over a period of four years with a contractual term of ten years. Such time-based stock options use the Black-Scholes option pricing model to determine grant date fair value.

For the years ended December 31, 2025 and 2024, the Company recorded $0.1 million and $0.2 million of stock-based compensation, respectively, in relation to subsidiary EIPs. As of December 31, 2025, there was $0.2 million of total unrecognized stock-based compensation expense related to unvested EIP awards to employees and non-employee directors expected to be recognized over a weighted-average period of approximately 3.2 years.

Stock-Based Compensation

Stock-based compensation expense is allocated to either Research and development or General and administrative expense on the consolidated statements of operations based on the cost center to which the option holder belongs.