The Company adopted the 2012 Equity Incentive Plan, or the 2012 Plan, in May 2012. Including subsequent increases, the Company had reserved 933,333 shares for issuance. On December 31, 2023, there were 65,728 shares reserved for issuance and no shares available for future grant.

The Company adopted the 2020 Equity Incentive Plan, or the 2020 Plan, in June 2020. The Company reserved 1,400,000 shares for issuance plus a carryover of 71,085 shares from the 2012 Plan for a total of 1,471,085 shares. In addition, returning shares from the 2012 Plan are available for issuance under the 2020 Plan. As of December 31, 2023, there were 400,167 shares reserved for issuance and 1,302,411 shares available for future grant.

Stock options generally vest ratably in either quarterly or annual installments over three or four years, commencing on the first anniversary of the grant date and have contractual terms of ten years. Stock options to directors generally vest ratably over one or two years and have contractual terms of ten years. Stock options are valued using the Black-Scholes option pricing model and compensation is recognized based on such fair value over the period of vesting on a straight-line basis.

There were no proceeds from option exercises during the year ended December 31, 2023 as compared to $21 thousand during the year ended December 31, 2022. The intrinsic value of these options amounted to $26 thousand for the year ended December 31, 2022.

Stock option activity under the Company's stock options plans for the years ending December 31, 2023 and 2022 were as follows:


(in thousands, except share and per share data)	Number of Shares			Weighted- Average Exercise Price		Weighted- Average Contractual Term (Years)		Aggregate Intrinsic Value
Outstanding, December 31, 2021		711,058		$	43.05
Granted		313,167			16.14
Exercised		(1,750	)		12.00
Cancelled		(328,566	)		50.10
Outstanding, December 31, 2022		693,909		$	27.60
Granted		259,122			7.35
Cancelled		(487,133	)		17.70
Outstanding, December 31, 2023		465,898		$	26.85		7.81	$	—
Options exercisable, December 31, 2023		415,376		$	28.80		7.64	$	—
Options available for future grant, December 31, 2023		1,302,411

On December 31, 2023, total unrecognized compensation costs related to non-vested stock options outstanding amounted to $0.4 million, which is expected to be recognized over a weighted-average period of 1.53 years.

For the year ended December 31, 2023 the Company did not issue shares of restricted stock and issued 18,667 in the year ended December 31, 2022 to directors. There were no repurchases by the Company for the year ended December 31, 2023. During the year ended December 31, 2022, the Company repurchased 1,250 shares at a price of $36.15 per share to cover payroll taxes for one employee exercise, which is in accordance with the original terms of the award.

A summary of the status of restricted stock as of December 31, 2023 and 2022 is as follows:


	Number of Shares			Weighted-Average Grant Date Fair Value
Unvested, December 31, 2021		79,905		$	31.54
Granted		18,667			12.30
Vested		(20,441	)		34.21
Cancelled		(15,527	)		47.23
Unvested, December 31, 2022		62,604		$	21.04
Vested		(33,322	)		17.94
Cancelled		(29,282	)		24.60
Unvested, December 31, 2023		—		$	—

As of December 31, 2023, there was no unrecognized stock-based compensation expense related to non-vested restricted stock arrangements.