Stock-based compensation expense for the three and six months ended June 30, 2026 and 2025 was classified in the condensed consolidated statement of operations as follows (in thousands):

As of June 30, 2026, the remaining unrecognized stock-based compensation cost from all plans to be recognized in future periods totaled $45.8 million.

2020 Plan

In June 2020, the Company’s board of directors adopted the 2020 Stock Option and Incentive Plan (the “2020 Plan”) and reserved 2.9 million shares of common stock for issuance under this plan. The 2020 Plan includes automatic annual increases. The increase on January 1, 2026 was 7.1 million shares. As of June 30, 2026, 4.8 million shares remain available for grant.

The 2020 Plan authorizes the board of directors or a committee of the board to grant incentive stock options, nonqualified stock options, restricted stock awards and restricted stock units ("RSUs") to eligible officers, employees, consultants and directors of the Company. Options generally vest over a period of four years and have a contractual life of ten years from the date of grant.

2025 Inducement Plan

In December 2025, the Company’s board of directors adopted the Compass Therapeutics, Inc. 2025 Inducement Plan (the “Inducement Plan”). The maximum number of shares of Stock reserved and available for issuance under the Inducement Plan is four million shares. As of June 30, 2026, a total of two million options were granted as part of the Inducement Plan to two new officers as a material inducement for those officers to join the Company.

Stock Options:

The following table summarizes the stock option activity for the 2020 Plan and the Inducement Plan:

For the six months ended June 30, 2026, the weighted average grant date fair value for options granted was $3.71. The intrinsic value for options vested as of June 30, 2026, was $1.6 million. As of June 30, 2026, the total unrecognized compensation cost related to outstanding options was $40.7 million, to be recognized over a weighted average period of 1.5 years.

For the six months ended June 30, 2025, the weighted average grant date fair value for options granted was $2.68. The intrinsic value for options vested as of June 30, 2025, was $2.1 million. As of June 30, 2025, the total unrecognized compensation cost related to outstanding options was $19.5 million, to be recognized over a weighted average period of 1.5 years.

The weighted average assumptions used in the Black-Scholes pricing model to determine the fair value of stock options granted during the six months ended June 30, 2026 and 2025 were as follows:

RSUs:

The following table summarizes the RSU activity for the 2020 Plan and the Inducement Plan:

The weighted average price per share is the weighted grant price based on the closing market price of each of the stock grants. The weighted average fair value is the weighted average share price times the number of shares. As of June 30, 2026, the remaining unrecognized compensation cost related to RSUs to be recognized in future periods totaled $5.1 million, which is expected to be recognized over a weighted average period of 1.6 years.