The Company’s stock-based compensation expense, including options and restricted stock by category is as follows (in thousands):


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2020		2019		2020		2019
Cost of revenue	$	24	$	1	$	24	$	2
Engineering and product development		288		32		343		119
Marketing and sales		490		57		548		116
General and administrative		811		214		1,162		279

	$	1,613	$	304	$	2,077	$	516

As of June 30, 2020, unrecognized compensation cost (in thousands) related to unvested options and unvested restricted stock and the weighted average term of such equity instruments is as follows:


Remaining expense	$	1,442
Weighted average term		1.0

The Company’s restricted stock awards typically vest in either one year or three equal annual installments with the first installment vesting one year from grant date.

The Company granted 0 and 14,000 shares of restricted stock during

the six-month

periods

ended June 30, 2020

and

2019

, respectively

The Company’s aggregate intrinsic value for stock options and restricted stock outstanding is as follows (in thousands):


	As of
	June 30,
Aggregate intrinsic value	2020		2019
Stock options	$	8,992	$	2,273
Restricted stock		709		1,674

The Company issued 8,167 and 44,966 shares of common stock upon the exercise of outstanding stock options in the three and

six-month

periods

ended June 30, 2020

respectively. The Company received cash proceeds of approximately $36,000 and $231,000 in the three and

six-month

periods

ended June 30, 2020

respectively. The intrinsic value of restricted shares that vested in the

six

months

ended June 30, 2020 was $0.4 million

There was no vesting of restricted shares in the three months ended June 30, 2020.

Employee Stock Purchase Plan

In December 2019, the 2019 Employee Stock Purchase Plan (“ESPP”) was adopted by the Company’s Board of Directors and approved by stockholders, effective January 1, 2020.

The ESPP provides for the issuance of up to 950,000 shares of common stock, subject to adjustment in the event of a stock split, stock dividend or other change in the Company’s capitalization. The ESPP may be terminated or amended by the Board of Directors at any time. Certain amendments to the ESPP require stockholder approval.

Substantially all of the Company’s employees whose customary employment is for more than 20 hours a week are eligible to participate in the ESPP. Any employee who owns 5% or more of the voting power or value of the Company’s shares of common stock is not eligible to participate in the ESPP.

Any eligible employee can enroll in the ESPP as of the beginning of a respective quarterly accumulation period. Employees who participate in the ESPP may purchase shares by

authorizing payroll deductions of up to 15% of their base compensation during an accumulation period. Unless the participating employee withdraws from participation, accumulated payroll deductions are used to purchase shares of common stock on the last business day of the accumulation period (the “Purchase Date”) at a price equal to 85% of the lower of the fair market value on (i) the Purchase Date or (ii) the first day of such accumulation period. Under applicable tax rules, no employee may purchase more than $25,000 worth of common stock, valued at the start of the purchase period, under the ESPP in any calendar year.

The Company issued

16,392

and 34,857 shares under the ESPP in the three and

six-month

periods ended June 30, 2020, respectively. The Company recorded approximately

30,000

and $

64,000

of stock-based compensation expense pursuant to ESPP for the three and

six-month

periods ended June 30, 2020, respectively. The second accumulation period under the ESPP commenced on April 1, 2020 and was completed on June 30, 2020, and the related shares purchased by the participants were issued in July 2020. As of June 30, 2020, the Company recorded a liability

of $

94,000

to employee withholdings in connection with the ESPP accumulation period ended June 30, 2020, which was included as a component of accrued expenses and other current liabilities.