The Company previously granted stock options under its 2006 Stock Incentive Plan (the “2006 Plan”) and its 2015 Stock Incentive Plan (the “2015 Plan”). As of September 30, 2022 there were 1,986,843 stock options outstanding under the 2006 Plan and 2015 Plan and no remaining stock options available to be granted under such plans.

On March 12, 2019, the Company’s board of directors adopted, and, on March 14, 2019 the Company’s stockholders approved, the Precision BioSciences, Inc. 2019 Incentive Award Plan (“2019 Plan”) and the 2019 Employee Stock Purchase Plan (“2019 ESPP”), both of which became effective on March 27, 2019.

The 2019 Plan provides for the grant of incentive stock options, non-qualified stock options, stock appreciation rights, restricted stock, restricted stock units and other share-based awards. The number of shares available for issuance under the 2019 Plan initially equaled 4,750,000 shares of common stock. The 2019 Plan provides for an annual increase to the number of shares of common stock available for issuance on the first day of each calendar year beginning January 1, 2020 and ending on and including January 1, 2029 by an amount equal to the lesser of (i) 4% of the aggregate number of shares of common stock outstanding on the final day of the immediately preceding calendar year and (ii) such smaller number of shares of common stock as determined by the board of directors. As of September 30, 2022, the aggregate number of shares available for issuance under the 2019 Plan has been increased by 6,589,999 pursuant to this provision. Any shares that are subject to awards outstanding under the Company’s 2006 Plan and 2015 Plan as of the effective date of the 2019 Plan that expire, lapse, or are terminated, exchanged for cash, surrendered, repurchased, or canceled without having been fully exercised or forfeited, to the extent so unused, will become available for award grants under the 2019 Plan. As of September 30, 2022, 1,435,635 shares were available to be issued under the 2019 Plan. The 2019 Plan had 9,070,937 stock options and 1,936,252 restricted stock units (“RSUs”) outstanding as of September 30, 2022.

Up to 525,000 shares of the Company’s common stock were initially reserved for issuance under the 2019 ESPP. The 2019 ESPP provides for an annual increase to the number of shares available for issuance on the first day of each calendar year beginning January 1, 2020 and ending on and including January 1, 2029 by an amount equal to the lesser of (i) 1% of the shares outstanding on the final day of the immediately preceding calendar year and (ii) such smaller number of shares as is determined by our board of directors. As of September 30, 2022, the aggregate number of shares available for issuance under the 2019 ESPP has been increased by 1,647,499 shares pursuant to this provision. The purchase price of the shares under the 2019 ESPP, in the absence of a contrary designation, will be 85% of the lower of the fair market value of our common stock on the first trading day of the offering period or on the purchase date. As of September 30, 2022, the Company had issued 447,787 shares under the 2019 ESPP. As of September 30, 2022, 1,724,712 shares were available to be issued under the 2019 ESPP. The Company recognized share-based compensation expense related to the ESPP of $0.1 million and $0.3 million during the nine months ended September 30, 2022 and 2021, respectively.

On August 9, 2021, the Company’s board of directors approved the adoption of the Precision BioSciences, Inc. 2021 Employment Inducement Incentive Award Plan (as amended, the “Inducement Award Plan”).

The Inducement Award Plan provides for the grant of non-qualified stock options, stock appreciation rights, restricted stock, RSUs and other share-based awards to newly hired employees who have not previously been an employee or member of the board, or an employee who is being rehired following a bona fide period of non-employment by the Company. No more than 9,000,000 shares of the Company’s common stock may be issued under the Inducement Award Plan. As of September 30, 2022, 6,024,715 shares were available to be issued under the Inducement Award Plan. The Inducement Award Plan had 2,751,623 stock options and 223,662 RSUs outstanding as of September 30, 2022.

The Company recorded employee and nonemployee share-based compensation expense as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2022		2021		2022		2021
Employee	$	4,215	$	4,151	$	11,977	$	10,942
Nonemployee		918		400		2,684		1,137
	$	5,133	$	4,551	$	14,661	$	12,079

Share-based compensation expense is included in the following line items in the condensed consolidated statements of operations (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2022		2021		2022		2021
Research and development	$	2,069	$	2,563	$	6,227	$	6,916
General and administrative		3,064		1,988		8,434		5,163
	$	5,133	$	4,551	$	14,661	$	12,079

Determining the appropriate fair value model to measure the fair value of the stock option grants on the date of grant and the related assumptions requires judgment. The fair value of each stock option grant is estimated using a Black-Scholes option-pricing model on the date of grant as follows:


	Three Months Ended September 30,			Nine Months Ended September 30,
	2022			2022
Estimated dividend yield		0.00	%		0.00	%
Weighted-average expected stock price volatility		80.34	%		79.25	%
Weighted-average risk-free interest rate		3.11	%		2.42	%
Expected term of options (in years)		6.06			6.08
Weighted-average fair value per option	$	1.09		$	1.94

The expected volatility rates are estimated based on the actual volatility of a peer group comprising the Company and other comparable public companies over the expected term. The expected term represents the average time that stock options are expected to be outstanding. The Company does not have sufficient history of exercising stock options to estimate the expected term of employee stock options and thus utilizes a weighted value considering actual history and estimated expected term based on the midpoint of final vest date and expiration date. The risk-free rate is based on the United States Treasury yield curve at the time of grant for the expected term of the option.

The following table summarizes activity in the Company’s stock option plans for the nine months ended September 30, 2022:


	Outstanding Option Shares			Weighted-Average Exercise Price
Balance as of January 1, 2022		9,920,314		$	9.28
Granted		6,191,412			2.80
Exercised		(330,359	)		1.17
Forfeited/canceled		(1,971,964	)		9.65
Balance as of September 30, 2022		13,809,403		$	6.52

The intrinsic value of stock options exercised was $0.7 million and $14.9 million during the nine months ended September 30, 2022 and 2021, respectively.

During the nine months ended September 30, 2022, the Company granted 1,826,307 RSUs with a grant date fair value of $6.6 million. The fair value of each award was determined based on the closing market price of the Company’s common stock on the date of grant. The fair value of the RSUs will be recognized as expense over the requisite vesting period.

The following table summarizes the Company’s RSU activity for the nine months ended September 30, 2022:


	RSU Awards			Weighted-Average Grant Date Fair Value
Unvested RSUs as of January 1, 2022		773,503			11.29
Granted		1,826,307		$	3.64
Forfeited		(175,781	)		7.19
Vested		(264,115	)		11.34
Unvested RSUs as of September 30, 2022		2,159,914		$	5.15

There was approximately $34.7 million of total unrecognized compensation cost related to unvested stock options and RSUs as of September 30, 2022, which is expected to be recognized over a weighted-average period of 2.5 years.