Bolt Biotherapeutics, Inc. Stock Compensation Disclosure

10. Stock-Based Compensation

2021 Equity Incentive Plan and 2021 Employee Stock Purchase Plan

In January 2021, the Company’s board of directors adopted the 2021 Equity Incentive Plan (the “2021 Plan”) and the Company’s stockholders approved the 2021 Plan. The 2021 Plan authorized issuance of up to 8,075,000 shares of common stock and it became effective upon the execution of the underwriting agreement for the Company’s IPO. In addition, the number of shares of common stock reserved for issuance under the 2021 Plan automatically increases on the first day of January of each calendar year that commences after the 2021 Plan became effective and continuing through and including January 1, 2031, in an amount equal to 5% of the total number of shares of the Company’s common stock outstanding on December 31, or a lesser number of shares determined by the Company's board of directors or compensation committee. As a result, common stock reserved for issuance under the 2021 Plan was increased by 1,905,730 shares on January 1, 2024. In connection with the workforce reduction described in Note 8 “Restructuring”, the Company entered into consulting agreements with certain officers of the Company, pursuant to which a total of 1,615,713 stock options previously granted to the officers were canceled on July 15, 2024.

In addition, in January 2021, the Company’s board of directors and stockholders adopted the 2021 Employee Stock Purchase Plan (the “ESPP”). The ESPP authorized issuance of up to 420,000 shares of common stock and it became effective upon the execution of the underwriting agreement for the Company’s IPO. The ESPP permits participants to purchase common stock through payroll deductions of up to 15% of their eligible compensation. Employees purchase shares of common stock at a price per share equal to 85% of the lower of the fair market value at the start or end of six-month purchase periods within the two-year offering period. In addition, the number of shares of common stock reserved for issuance under the ESPP automatically increases on January 1 of each calendar year that commences after the ESPP became effective and continuing through and including January 1, 2031, by the lesser of (1) 1% of the total number of shares of the Company's common stock outstanding on December 31 of the preceding calendar year, (2) 840,000 shares, and (3) a number of shares determined by the Company's board of directors. As a result, common stock reserved for issuance under the ESPP was increased by 381,146 shares on January 1, 2024. During the years ended December 31, 2024 and 2023, 183,378 and 254,169 shares were issued under the ESPP, respectively.

Performance and Service-Based Stock Options

In September 2020, the compensation committee of the Company’s board of directors granted 526,018 options to employees that would commence vesting upon the closing of the Series C-2 financing and generally vest monthly over 48 months (the “Performance Awards”). The Company recognizes expense based on the fair value of the Performance Awards over the estimated service period (under the graded vesting method) to the extent the achievement of the related performance criteria is estimated to be probable. The Company determined that the financing milestone was achieved during January 2021. Accordingly, the Company recognized stock-based compensation expenses related to the Performance Awards of approximately $35,000 and $0.1 million for the years ended December 31, 2024 and 2023, respectively. The weighted-average grant date fair value of the Performance Awards was $3.24 per share.

The intrinsic value of options exercised was zero and $2,000 during the year ended December 31, 2024 and 2023, respectively. The fair value of options vested was $1.1 million and $2.1 million during the years ended December 31, 2024 and 2023, respectively. As of December 31, 2024, there was approximately $2.8 million of unrecognized stock-based compensation related to unvested stock options, which the Company expects to recognize over a weighted-average period of 1.28 years.

Expected Term–The expected term of options granted represents the period of time that the options are expected to be outstanding. Due to the lack of historical exercise history, the expected term of the Company’s employee stock options has been determined utilizing the simplified method for awards that qualify as plain-vanilla options, which use the midpoint between the vesting date and the expiration date of each option.

Expected Volatility–The estimated volatility was based on the historical volatility of the common stock of a group of publicly traded companies deemed comparable to the Company.

Risk-Free Interest Rate–The risk-free interest rate is the implied yield in effect at the time of the option grant based on

U.S. Treasury securities with contract maturities equal to the expected term of the Company’s stock options.

Dividend Rate–The Company has not paid any cash dividends on common stock since inception and does not anticipate paying any dividends in the foreseeable future. Consequently, an expected dividend yield of zero was used.

Fair Value of Common Stock– The fair value of the Company’s common stock is determined by the closing price, on the date of grant, of its common stock, which is traded on the Nasdaq Capital Market.

Stock-Based Compensation Expense

Restricted Stock Units

In December 2021, the Company issued 336,000 restricted stock units under the 2021 Plan at a grant date fair value of $4.51 per share. These restricted stock units vested in equal quarterly installments over three years, subject to the employee's continued employment with, or services to, the Company on each vesting date. Each restricted stock unit represents the right to receive one share of the Company's common stock when and if the applicable vesting conditions are satisfied.

As of December 31, 2024, total unrecognized stock-based compensation expense relating to unvested restricted stock units was zero and the weighted-average remaining vesting period was zero years.

As of December 31, 2024, all restricted stock awards were vested and none were outstanding.