STOCK-BASED AWARDS

9 Months Ended

Sep. 30, 2020

Share-based Payment Arrangement [Abstract]

Stock Options

Stock option activity is summarized as follows (in thousands, except per share and term information):


	Number of Shares	Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term	Aggregate Intrinsic Value1
Outstanding, December 31, 2019	2,851	$	30.97	3.1	$	78,580

Exercised	(774)	12.09
Forfeited	(174)	42.43
Outstanding, September 30, 2020	1,903	$	37.62	2.9	$	9,347

Exercisable at September 30, 2020	1,903	$	37.62	2.9	$	9,347
Vested and expected to vest at September 30, 2020	1,903	$	37.62	2.9	$	9,347


1 Based on the Company’s closing stock price of $36.36 on September 30, 2020 and $58.55 on December 31, 2019.

There were no stock options granted during the three and nine months ended September 30, 2020 and 2019.

Restricted Stock Units

Restricted stock unit (“RSU”) activity is summarized as follows (shares in thousands):


	Number of Shares	Weighted- Average Grant Date Fair Value
Unvested shares at December 31, 2019	3,756	$	47.76
Granted	2,019	34.39
Forfeited	(296)	46.69
Vested	(1,502)	43.44
Unvested shares at September 30, 2020	3,977	$	42.68

Unrecognized compensation expense related to unvested RSUs was $125.2 million at September 30, 2020, which is expected to be recognized over a weighted-average period of 2.5 years.

Performance-Based Restricted Stock Units

Performance-based restricted stock unit (“PRSU”) activity is summarized as follows (shares in thousands):


	Number of Shares	Weighted- Average Grant Date Fair Value
Unvested shares at December 31, 20191	1,752	$	44.21
Granted	720	36.06
Forfeited	(261)	40.69

Unvested shares at September 30, 20201	2,211	$	41.97

1 Assumes maximum achievement of the specified financial targets.

Unrecognized compensation expense related to unvested PRSUs was $14.9 million at September 30, 2020, which is expected to be recognized over a weighted-average period of 1.6 years.

Employee Stock Purchase Plan

Under the Company’s 2010 Employee Stock Purchase Plan (“ESPP”), eligible employees are granted the right to purchase shares at the lower of 85% of the fair value of the stock at the time of grant or 85% of the fair value at the time of exercise. The right to purchase shares is granted semi-annually, in June and December, for six month offering periods. As of and for the three months ended September 30, 2020, no shares were purchased under the ESPP, and 4,326,341 shares remained available for issuance.

Stock-Based Compensation

Stock-based compensation expense is reflected in the accompanying condensed consolidated statements of operations as follows (in thousands):


	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2020		2019		2020		2019
Cost of revenue	$	2,205	$	1,748	$	7,028	$	4,670
Sales and marketing	7,197		7,915		21,409		20,771
Research and development	4,283		4,285		11,807		12,800
General and administrative	4,047		5,570		14,553		17,473
Restructuring	192		—		400		—
Total	$	17,924	$	19,518	$	55,197	$	55,714