Stock-Based Awards (Tables)

12 Months Ended

Dec. 31, 2020

Share-based Payment Arrangement [Abstract]

Summary of Stock Option Activity

A summary of the Plan activity and related information follows (in thousands except weighted average exercise price):

	Shares Available for Grant		Number of Options Outstanding		Number of RSUs Outstanding		Weighted Average Exercise Price
January 1, 2019		1,731		2,269		-	$	2.42
Restricted stock units granted		(100)		-		50		-
Options granted		(677)		677		-		3.92
Options forfeited and cancelled		100		(100)		-		3.48
December 31, 2019		1,054		2,846		50		2.74
Options granted		(303)		303		-		0.74
Options expired/forfeited		295		(295)		-		2.89
Restricted stock units vested		-		-		(22)		-
December 31, 2020		1,046		2,854		28	$	2.51
Options exercisable at December 31, 2020				1,954			$	2.59

Schedule of Stock Based Compensation Expense

AgeX recorded stock-based compensation expense in the following categories on the accompanying consolidated statements of operations for the years ended December 31, 2020 and 2019 (in thousands):

	Year Ended December 31,
	2020		2019
Research and development	$	82	$	133
General and administrative		851		1,774
Total stock-based compensation expense	$	933	$	1,907

Schedule of Weighted Average Assumptions to Calculate Fair Value of Stock Options

The weighted-average estimated fair value of stock options granted during the years ended December 31, 2020 and 2019 was $0.53 per share and $2.45 per share, respectively, using the Black-Scholes option pricing model with the following weighted-average assumptions:

	Year Ended December 31,
	2020		2019
Expected life (in years)		6.08		6.01
Risk-free interest rates		0.45%		1.96%
Volatility		87.86%		74.53%
Dividend yield		-%		-%