The Company maintained the 2008 Stock Incentive Plan, or the 2008 Plan, for employees, consultants, advisors, and directors. The 2008 Plan provided for the granting of incentive and non-qualified stock option and restricted stock awards as determined by the Board of Directors. In connection with the Merger, all outstanding awards issued under the 2008 Plan were cancelled, and the Board of Directors formally terminated the 2008 Plan.

In June 2016, the Company’s stockholders approved the 2016 Incentive Award Plan, or the 2016 Plan, which authorized 40,341 shares of common stock for future issuance under the 2016 Plan and the Company ceased granting awards under the 2008 Plan. Upon the effective date of the 2016 Plan, awards issued under the 2008 Plan remained subject to the terms of the 2008 Plan. Awards granted under the 2008 Plan that expired, lapsed or terminated became available under the 2016 Plan as shares available for future grants.

Additionally, pursuant to the terms of the 2016 Plan, the Board of Directors is authorized to grant awards with respect to common stock, and may delegate to a committee of one or more members of the Board of Directors or executive officers of the Company the authority to grant options and restricted stock units. On December 9, 2020, the Board of Directors established a Stock Option Committee authorized to grant awards to certain employees and consultants subject to conditions and limitations within the 2016 Plan. In January 2024, the number of shares of common stock that may be issued under the 2016 Plan was increased by 215,903. In June 2024, the Company’s stockholders approved an amendment and restatement of the 2016 Plan to reserve an additional 3,466,544 shares of its common stock for issuance. As of September 30, 2024, 3,511,101 shares remain available for future issuance under the 2016 Plan.

In September 2018, the Company’s 2018 Employment Inducement Incentive Award Plan, or the 2018 Inducement Incentive Award Plan, was adopted by the Board of Directors without stockholder approval pursuant to Rule 5635(c)(4) of the Nasdaq Stock Market LLC listing rules, which authorized 39,166 shares of its common stock for issuance. In March 2019, the Board of Directors approved an amendment and restatement of the 2018 Inducement Incentive Award Plan to reserve an additional 66,667 shares of the Company’s common stock for issuance thereunder. In December 2023, the Board of Directors approved an amendment and restatement of the 2018 Inducement Incentive Award Plan to reserve an additional 60,833 shares of the Company’s common stock for issuance thereunder. In June 2024, the Board of Directors approved an amendment and restatement of the 2018 Inducement Incentive Award Plan to reserve an additional 360,000 shares of the Company’s common stock for issuance thereunder. As of September 30, 2024, there are 253,377 shares available for future grant under the 2018 Inducement Incentive Award Plan.

In accordance with the Merger Agreement, the Company assumed Old Cartesian’s 2016 Stock Incentive Plan, or the Old Cartesian Plan. The Old Cartesian Plan permits the granting of options or restricted stock to employees, officers, directors, consultants and advisors to the Company. The unvested common stock options and Series A Preferred Stock options assumed by the Company in connection with the Merger generally vest over a four-year period. Additionally, the stock options granted have a contractual term of ten years and only full shares can be exercised as per the individual award agreements. As of September 30, 2024, there are 27,270 shares available for future grant under the Old Cartesian Plan.

In connection with the Merger, the outstanding stock options to purchase Old Cartesian common stock were converted into stock options to purchase 776,865 shares of common stock and 14,112.299 shares of Series A Preferred Stock of the Company. These replacement awards were revalued at their acquisition-date fair value and then attributed to pre and post-combination service. This resulted in $2.6 million attributed to post-combination service to be recognized as stock-based compensation expense over the remaining terms of the replacement awards, of which $0.3 million and $1.0 million was recognized as research and development expense in the consolidated statements of operations and comprehensive income (loss) during the

Stock-based compensation expense by classification included within the consolidated statements of operations and comprehensive income (loss), including $1.5 million recognized as stock-based compensation expense upon the achievement of a technical milestone by Ginkgo Bioworks Holdings, Inc., or Ginkgo, during the nine months ended September 30, 2023 as described in Note 15, was as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2024		2023		2024		2023
Research and development	$	799	$	1,189	$	2,287	$	5,058
General and administrative	896		1,132		2,430		3,322
Total stock-based compensation expense	$	1,695	$	2,321	$	4,717	$	8,380

The estimated grant date fair values of stock option awards granted under the 2016 Plan and the 2018 Inducement Incentive Award Plan were calculated using the Black-Scholes option pricing model based on the weighted-average assumptions in the following table. No stock options were granted during the three months ended September 30, 2023.


	Three Months Ended September 30,			Nine Months Ended September 30,
	2024				2024			2023
Risk-free interest rate	4.05		%		4.04		%	3.95		%
Dividend yield	—				—			—
Expected term (in years)	6.23				6.20			5.94
Expected volatility	94.98		%		95.07		%	94.64		%
Weighted-average fair value of common stock	$	17.97			$	19.79		$	34.50

The expected term of the Company's stock options granted has been determined utilizing the “simplified” method for awards that qualify as “plain-vanilla” options. Under the simplified method, the expected term is presumed to be the midpoint between the vesting date and the end of the contractual term. The Company utilizes this method due to lack of historical exercise data and the plain nature of its stock-based awards.

The weighted-average grant date fair value of stock options granted was $14.23 during the three months ended September 30, 2024, and $15.75 and $26.89 during the nine months ended September 30, 2024 and 2023, respectively.


				Weighted-average
	Number of			remaining	Aggregate
	common stock	Weighted-average		contractual term	intrinsic value
	options	exercise price ($)		(in years)	(in thousands)









Outstanding at December 31, 2023	776,865	$	2.97	6.50	$	13,760
Granted	908,675	$	19.79
Converted from options for Series A Preferred Stock	470,403	$	2.40
Exercised	(106,073)	$	3.12
Forfeited	(77,681)	$	17.12
Outstanding at September 30, 2024	1,972,189	$	10.02	7.11	$	15,207

Vested at September 30, 2024	976,876	$	2.84	5.09	$	13,020
Vested and expected to vest at September 30, 2024	1,830,212	$	9.26	6.94	$	15,190


	Number of			Weighted-average
	Series A			remaining	Aggregate
	Preferred Stock	Weighted-average		contractual term	intrinsic value
	options	exercise price ($)		(in years)	(in thousands)









Outstanding at December 31, 2023	14,112.299	$	79.94	5.91	$	8,601




Converted to options for common stock	(14,112.299)	$	79.94
Outstanding at September 30, 2024	—	$	—

As a result of the approval of the Conversion Proposal on March 27, 2024, all conditions that could have required cash redemption of the Series A Preferred Stock underlying the stock options were satisfied. Since the Series A Preferred Stock is no longer redeemable, the associated balances of the stock options to purchase Series A Preferred Stock were reclassified from mezzanine equity to additional paid-in capital during the first quarter of 2024.

Following the Automatic Conversion, all options to purchase Series A Preferred Stock were converted into options to purchase common stock with adjustments to the underlying number of shares of common stock determined by multiplying the number of shares of Series A Preferred Stock by 33.333 and rounding down to the nearest whole number of shares and the per-share exercise price by dividing the per-share exercise price of Series A Preferred Stock by 33.333 and rounding the resulting exercise price up to the nearest whole cent.

During the nine months ended September 30, 2024, the Company granted 477,037 restricted stock unit awards with a weighted-average fair value of $19.86 per share based on the closing price of the Company’s common stock on the date of grant under the 2016 Plan and the Old Cartesian Plan, which generally vest over a four-year term. Forfeitures are estimated at the time of grant and are adjusted, if necessary, in subsequent periods if actual forfeitures differ from those estimates. The Company has estimated a forfeiture rate of 10% for restricted stock unit awards based on historical experience.

In June 2016, the Company approved the 2016 Employee Stock Purchase Plan, or the ESPP, which initially authorized 5,769 shares of common stock for future issuance under the ESPP to participating employees. As of September 30, 2024, 45,795 shares remain available for future issuance under the ESPP. In connection with the Merger, the Board of Directors suspended the offerings under the ESPP.