As of September 30, 2020, the Atea Pharmaceuticals 2013 Equity Incentive Plan, as amended (the “2013 Plan”), provided for the grant of incentive stock options, non-qualified stock options, restricted common stock awards and other awards for up to 10,979,971 shares of common stock to employees, officers, directors and consultants of the Company.

As of September 30, 2020, options to purchase 7,095,494 shares of common stock and 3,370,000 shares of restricted common stock had been granted under the 2013 Plan, and there were 514,477 shares of common stock remaining available for future issuance.

Restricted stock awards generally include vesting and risk of forfeiture provisions that lapse upon satisfaction of performance conditions or over time periods commencing on the grant date and concluding on the third or fourth anniversary of the grant date. The Company has granted awards totaling 200,000 shares of restricted common stock to a consultant pursuant to the 2013 Plan for consulting and business development services. The consultant paid $1.21 per share and an aggregate of $121 for 100,000 of the shares of restricted common stock in 2016 and $1.24 per share and an aggregate of $124 for 100,000 of the shares of restricted common stock in 2018. These awards of restricted common stock will vest, and the risk of forfeiture will lapse upon satisfaction of performance conditions detailed in each award. As of September 30, 2020, the performance conditions were not yet probable of being met and, as a result, no compensation expense has yet been recognized for these performance-based awards. The unvested and forfeitable common stock as of September 30, 2020, though legally issued, are excluded from issued and outstanding shares for accounting purposes. Amounts received for the unvested and forfeitable common stock totaling $245 are included in additional paid-in capital within stockholders’ deficit in the consolidated balance sheets. At September 30, 2020, total unrecognized compensation expense related to unvested restricted common stock was $370.

	Number of Shares			Weighted Average Exercise Price Per Share		Weighted Average Remaining Contractual Term (years)		Aggregate Intrinsic Value
Outstanding at January 1, 2020		3,911,633		$	1.50		8.5	$	3,915
Granted		3,408,861		$	6.38
Exercised		(18,747	)	$	1.43
Cancelled		(300,000	)	$	6.83
Outstanding at September 30, 2020		7,001,747		$	3.65		8.7	$	22,406
Options exercisable at September 30, 2020		2,857,918		$	1.47		7.4	$	15,371
Vested or expected to vest at September 30, 2020		7,001,747		$	3.65		8.7	$	22,406

The aggregate intrinsic value of options granted is calculated as the difference between the exercise price of the options and the estimated fair value of the Company’s common stock for those options that had exercise prices lower than the fair value of the Company’s common stock.

Option grants generally vest over a service period of three or four years and have a contractual term of ten years. As of September 30, 2020, total unrecognized compensation expense related to stock option awards was $14,923, which amount is being recognized over a remaining weighted average period of 3.7 years.

	Three Months Ended September 30,				Nine Months Ended September 30,
	2020		2019		2020		2019
Research and development expense	$	2,469	$	63	$	2,627	$	188
General and administrative		1,769		94		2,009		262
Total stock-based compensation expense	$	4,238	$	157	$	4,636	$	450