On March 16, 2023, the Zura Bio Limited 2023 Equity Incentive Plan (the “Equity Incentive Plan”) was approved, became effective on March 19, 2023, and was amended on June 1, 2023 and June 17, 2026. The Equity Incentive Plan allows for the grant of share options, both incentive and nonqualified share options; stock appreciation rights, alone or in conjunction with other awards; restricted shares awards (“RSAs”) and restricted share units (“RSUs”); incentive bonuses, which may be paid in cash, shares, or a combination thereof; and other share-based awards to employees, officers, non-employee directors and other service providers. The Company has granted share options, RSUs and RSAs that generally vest over four years and expire after 10 years.

The Class A Ordinary Shares issuable under the Equity Incentive Plan are subject to an annual increase on January 1st of each calendar year beginning on January 1, 2024, and ending on and including January 1, 2029, in accordance with the Equity Incentive Plan.

On March 16, 2023, the Zura Bio Limited 2023 Employee Stock Purchase Plan (the “ESPP”) was approved and became effective on March 19, 2023. The ESPP enables eligible employees of the Company and designated affiliates to purchase Class A Ordinary Shares at a discount of 15%. As of June 30, 2026, the Company has not activated its ESPP.

The Class A Ordinary Shares reserved for future issuances under the Equity Incentive Plan and the ESPP increased in accordance with the respective plans on January 1, 2026. As of June 30, 2026, a maximum of 20,573,023 Class A Ordinary Shares were authorized for issuance under the Equity Incentive Plan and the ESPP, collectively.

The fair value of Equity Incentive Plan share options are estimated on the date of grant using the Black-Scholes option pricing model. The Company lacks significant company-specific historical and implied volatility information. Therefore, it estimates its expected share volatility based on the historical volatility of a publicly traded set of peer companies. Due to the lack of historical exercise history, the expected term of the Company’s share options has been determined using the simplified method, averaging the vesting period and the contractual life of the share options granted. The risk-free interest rate is determined by reference to the U.S. Treasury yield curve in effect at the time of grant of the award for time periods approximately equal to the expected term of the award. Expected dividend yield is zero based on the fact that the Company has never paid cash dividends and does not expect to pay any cash dividends in the foreseeable future.


	For the Six Months Ended June 30,
	2026			2025
Share price	$	5.89		$	1.19
Expected volatility	102.3		%	100.0		%
Risk-free rate	4.0		%	4.1		%
Expected term (in years)	6.0			6.1
Expected dividend yield	0		%	0		%


	Number of Options	Weighted Average Exercise Price (per share)		Weighted Average Remaining Contractual Life (Years)	Aggregate Intrinsic Value (in thousands)
Options outstanding as of December 31, 2025	16,463,011	$	2.40	8.2	$	48,866
Granted	8,676,478	$	5.89
Exercised	(716,853)	$	2.98
Cancelled	(3,547,753)	$	2.77
Options outstanding as of June 30, 2026	20,874,883	$	3.77	8.0	$	47,532
Options vested and exercisable as of June 30, 2026	8,910,434	$	2.22	6.6	$	33,128

As of June 30, 2026, there was approximately $40.3 million of total unrecognized share-based compensation expense related to options granted to employees, executives, and directors that is expected to be recognized over a weighted average period of 3.1 years.

Included in options outstanding as of June 30, 2026 and December 31, 2025 in the table above are 3,223,440 options and 2,843,814 options, respectively, to purchase Class A Ordinary Shares issued to certain directors, executives, and employees outside of the Equity Incentive Plan.

On January 21, 2026, the Company granted 505,881 options to purchase Class A Ordinary Shares (the “CEO Option Award”) to the Chief Executive Officer. The CEO Option Award will vest in full on the first date upon which both of the following goals are achieved, subject to the CEO’s continued service through such date: (a) the Company’s completion of an equity raise above a specified amount prior to a specified date, which condition was satisfied by the completion of the February 2026 Equity Offering, and (b) the volume-weighted average price of a Class A ordinary share of the Company equals or exceeds a specified price over a period of 30 consecutive trading days, prior to December 31, 2030. These awards have an exercise price of $6.32 and become exercisable when vested and both conditions are satisfied. These awards expire 10 years from the date of grant. The fair value of these Market-Based Share Options were estimated using a Monte Carlo valuation method.

The expense recognized related to Market-Based Share Options was $0.9 million and $0.1 million for the three months ended June 30, 2026 and 2025, respectively, and $1.6 million and $0.3 million for the six months ended June 30, 2026 and 2025, respectively.


	Number of RSUs	Weighted Average Grant Date Fair Value
Unvested RSUs outstanding as of December 31, 2025	583,282	$	5.99
Vested	(190,390)	$	5.53
Forfeited	(60,000)	$	6.84
Unvested RSUs outstanding as of June 30, 2026	332,892	$	6.09

As of June 30, 2026, there was approximately $1.4 million of total unrecognized share-based compensation expense related to RSUs granted to certain employees, executives, and directors under the Company’s Equity Incentive Plan that is expected to be recognized over a weighted average period of 0.9 years.

The expense recognized related to RSUs was $0.2 million and $0.4 million for the three months ended June 30, 2026 and 2025, respectively, and $0.6 million and $0.8 million for the six months ended June 30, 2026 and 2025, respectively.


	Number of RSAs	Weighted Average Grant Date Fair Value
Unvested RSAs outstanding as of December 31, 2025	249,997	$	8.16
Vested	(124,998)	8.16
Unvested RSAs outstanding as of June 30, 2026	124,999	$	8.16

As of June 30, 2026, there was approximately $0.7 million of total unrecognized share-based compensation expense related to RSAs granted to a certain director under the Company’s Equity Incentive Plan that is expected to be recognized over a weighted average period of 0.7 years.

The expense recognized related to RSAs was $0.3 million and $0.2 million for the three months ended June 30, 2026 and 2025, respectively, and $0.5 million and $0.5 million for the six months ended June 30, 2026 and 2025, respectively.


	For the Three Months Ended June 30,				For the Six Months Ended June 30,
	2026		2025		2026		2025
Research and development	$	1,013	$	376	$	1,582	$	894
General and administrative	3,444		3,356		7,883		6,482
Total share-based compensation expense	$	4,457	$	3,732	$	9,465	$	7,376