
	Three Months Ended June 30,				Six Months Ended June 30,
(in thousands)	2025		2024		2025		2024
General and administrative	$	2,462	$	2,742	$	5,050	$	5,533
Research and development	1,649		2,641		3,205		5,545
Total share-based compensation expense	$	4,111	$	5,383	$	8,255	$	11,078


	Three Months Ended June 30,				Six Months Ended June 30,
(in thousands)	2025		2024		2025		2024
Stock options	$	2,981	$	3,676	$	6,114	$	7,503
Restricted stock units	1,005		1,429		1,838		2,992
Employee share purchase plan	125		125		303		277
Performance restricted stock units	—		153		—		306
Total share-based compensation expense	$	4,111	$	5,383	$	8,255	$	11,078

Stock options granted under the 2022 Plan typically vest 1/8 on the six-month anniversary of the date of grant, and 1/48 each month thereafter for 42 months. All option awards generally expire 10 years from the date of grant.

The Company uses the Black-Scholes option-pricing model to estimate the fair value of stock options granted. The model assumptions include expected volatility, expected term, dividend yield, and the risk-free interest rate.

•Expected volatility: Due to the Company’s limited trading history for its common stock, the Company lacks sufficient historical data to support its expected stock price volatility. As such, the Company utilized a weighted approach by blending its own limited historical data with the volatilities of publicly traded biotechnology peers. The Company will continue to apply this approach until it has enough historical data to solely support its expected volatility.

•Expected term: The expected term represents the period of time that options are expected to be outstanding. Because the Company has limited historical exercise behavior, it determines the expected life assumption using the simplified method which is an average of the contractual term of the option and its vesting period.

•Dividend yield: The Company bases the expected dividend yield assumption on the fact that it has never paid cash dividends and has no present intention to pay cash dividends and, therefore, used an expected dividend yield of zero.

•Risk-free interest rate: The risk-free interest rate is based upon U.S. Treasury securities with remaining terms similar to the expected term of the share-based awards.

The fair value of each option issued was estimated on the grant date using the Black-Scholes option pricing model with the following weighted-average assumptions:


	Three Months Ended June 30,		Six Months Ended June 30,
	2025	2024	2025	2024
Risk-free interest rate	4.0%	4.3%	4.4%	4.3%
Expected volatility	54.6%	57.1%	52.7%	54.4%
Expected term (years)	5.8	5.6	6.0	6.0
Dividend yield	—%	—%	—%	—%


	Shares	Weighted-Average Exercise Price per Share		Weighted-Average Remaining Contractual Life (in years)	Aggregate Intrinsic Value (in thousands)(1)
Outstanding at January 1, 2025	16,880,628	$	6.40
Granted	4,141,388	$	3.42
Exercised	(11,983)	$	3.69
Cancelled/Expired	(1,672,006)	$	7.18
Outstanding at June 30, 2025	19,338,027	$	5.70	7.8	$	38
Exercisable at June 30, 2025	9,368,732	$	7.14	6.9	$	—

(1)The aggregate intrinsic value is calculated as the difference between the exercise price of the underlying options and the estimated fair value of the common stock for in the money options as of June 30, 2025.

As of June 30, 2025, unrecognized share-based compensation expense related to OmniAb options was $21.5 million, which is expected to be recognized over a remaining weighted-average period of approximately 1.27 years. As of June 30, 2025, unrecognized share-based compensation expense related to Ligand options was $0.1 million, which is expected to be recognized over a remaining weighted-average period of approximately 0.20 years.

The aggregate intrinsic value of OmniAb options exercised by OmniAb service providers during the six months ended June 30, 2025 was negligible. Cash received from OmniAb options exercised by OmniAb service providers during the six months ended June 30, 2025 was negligible.

RSUs generally represent the right to receive a certain number of shares of common stock subject to certain vesting conditions and other restrictions. RSUs generally vest over three years. The fair value of RSUs is determined by the closing market price on the grant date.


	Shares	Weighted-Average Grant Date Fair Value
Unvested balance at January 1, 2025	1,761,208	$	5.23
Granted	1,129,201	$	3.31
Vested	(665,316)	$	6.05
Forfeited	(197,520)	$	5.08
Unvested balance at June 30, 2025	2,027,573	$	3.90

As of June 30, 2025, unrecognized stock-based compensation expense related to OmniAb RSUs was $6.4 million, which is expected to be recognized over a remaining weighted-average period of approximately 1.41 years.

The aggregate intrinsic value of OmniAb RSUs vested for OmniAb service providers during the six months ended June 30, 2025 was $2.0 million.

Performance restricted stock units (“PRSUs”) generally represent the right to receive a certain number of shares of common stock based on the achievement of certain corporate performance or market goals and continued employment during the vesting period.

The Company’s PRSUs contain a market condition dependent upon the Company’s relative and absolute total stockholder return over a three-year period, with a payout range of 0% to 200% of the target shares granted. Share-based compensation expense for these PRSUs is measured using the Monte-Carlo valuation model and is not adjusted for the achievement, or lack thereof, of the market conditions.

The following table summarizes the PRSU activity during the six months ended June 30, 2025, under the Company’s equity awards plans:


	Shares	Weighted-Average Grant Date Fair Value
Unvested balance at January 1, 2025	94,749	$	16.11
Granted	—	$	—
Vested	(149,882)	$	16.11
Change in units based on performance achievement	55,133	$	16.11
Forfeited	—	$	—
Unvested balance at June 30, 2025	—	$	—

Under the Company’s 2022 Employee Stock Purchase Plan (the “ESPP”), eligible employees are entitled to purchase shares of common stock at a discount with accumulated payroll deductions. The ESPP provides for a series of overlapping 24-month offering periods comprising four six-month purchase periods. The purchase price for shares of common stock purchased under the ESPP is equal to 85% of the lesser of the fair market value of the Company’s common stock on (i) the first trading day of the applicable offering period or (ii) the last trading day of each six month purchase period in the applicable offering period.

As of June 30, 2025, the aggregate number of shares of the Company’s common stock that may be issued pursuant to rights granted under the ESPP equals 3,768,385 shares of the Company’s common stock. In addition, on the first day of each calendar year beginning on January 1, 2023 and ending on (and including) January 1, 2032, the number of shares available for issuance under the ESPP will be increased by a number of shares equal to the lesser of (i) 1% of the fully diluted shares outstanding on the final day of the immediately preceding calendar year, and (ii) such smaller number of shares as determined by the Company’s board of directors.

As of June 30, 2025, there was $0.8 million of unrecognized share-based compensation expense associated with the ESPP, which is expected to be recognized over a remaining weighted-average period of 1.31 years.