Stock-Based Compensation

3 Months Ended

Mar. 31, 2021

Stock-Based Compensation

Stock-Based Compensation

8. Stock-Based Compensation

The following table summarizes the stock option and award activity for the three months ended March 31, 2021:

		Options Outstanding
			Weighted-		Weighted-
	Options and		Average		Average	Aggregate
	Awards		Exercise		Remaining	Intrinsic
	Available for	Number of	Price Per		Contractual	Value
	Grant	Options	Share		Life (years)	(In thousands)
Balance—December 31, 2020	179,219	2,272,905	$	5.58	7.9	$	1,640
Authorized	570,946	—
RSUs granted	(236,605)	—
RSUs cancelled/forfeited	31,626	—
Options granted	(39,500)	39,500	$	5.52
Options exercised	—	(54,077)	$	2.66		$	194
Options cancelled/forfeited	134,857	(136,432)	$	3.96
Balance—March 31, 2021	640,543	2,121,896	$	5.75	6.1	$	2,359
Options exercisable—March 31, 2021		1,288,863	$	6.81	4.5	$	586

The total grant date fair value of options vested was $312,000 and $799,000 during the three months ended March 31, 2021 and 2020, respectively.

The weighted-average grant date fair value of employee options granted was $3.53 and $1.52 per share during the three months ended March 31, 2021 and 2020, respectively.

2016 Employee Stock Purchase Plan

In January 2021, there was an increase of 190,315 shares reserved for issuance under the Company’s Employee Stock Purchase Plan (ESPP) pursuant to the terms of the ESPP. The Company had 717,181 shares available for future issuance under the Company’s ESPP as of March 31, 2021. Employees did not purchase any shares during the three months ended March 31, 2021 and 2020.

Restricted Stock Units

The following table summarizes restricted stock units (RSUs) activity for the three months ended March 31, 2021:

	RSUs Outstanding
		Weighted-
		Average
	Number of	Grant Date
	Restricted Stock	Fair Value Per
	Units	Share
Balance—December 31, 2020	416,742	$	4.89
Granted	236,605		5.71
Vested	(136,709)		5.16
Cancelled/forfeited	(31,626)		4.12
Balance—March 31, 2021	485,012	$	5.26

The fair value of RSUs is determined on the date of grant based on the market price of the Company’s common stock on that date. As of March 31, 2021, there was $1.7 million of unrecognized stock-based compensation expense related to RSUs to be recognized over a weighted-average period of 1.5 years.

Stock-based Compensation Expense

As of March 31, 2021, there was $2.0 million of total unrecognized stock-based compensation expense related to unvested options which is expected to be recognized over a weighted-average period of 2.7 years. Compensation cost capitalized within inventory at March 31, 2021 and at December 31, 2020 was not material.