Stockholders' Equity (Tables)

3 Months Ended

Mar. 31, 2016

Schedule of Common Stock Reserved for Future Issuance

Shares of common stock reserved for future issuance related to outstanding equity awards, common stock warrants, and employee equity incentive plans were as follows (in thousands):



		March 31, 2016
Stock options outstanding		5,980
Restricted stock units outstanding		2,459
Shares available for future grant under 2014 Plan		6,482
Shares available for future issuance under ESPP		1,423
Common stock warrants outstanding		132
Total shares of common stock reserved		16,476

Schedule of Stock Option Activity

A summary of the Company’s stock option activity during the three months ended March 31, 2016 is as follows (in thousands, except years and per share data):



	Number of Shares		Weighted Average Exercise Price		Weighted Average Remaining Contractual Life (Years)	Aggregate Intrinsic Value
Outstanding as of December 31, 2015	6,092		$	4.58
Options granted (weighted average grant date fair value of $3.81 per share)	644		8.13
Options exercised	(499	)	4.81
Options forfeited or expired	(257	)	6.80
Outstanding as of March 31, 2016	5,980		$	4.85	6.6	$	26,039

Schedule of RSU Activity

A summary of the Company's restricted stock unit ("RSU") activity during the three months ended March 31, 2016 is as follows (in thousands, except per share data):



	Number of Shares		Weighted Average Grant Date Fair Value Per Share
Outstanding as of December 31, 2015	1,818		$	5.01
RSUs granted	820		7.98
RSUs vested and released	(128	)	4.98
RSUs forfeited	(51	)	4.96
Outstanding as of March 31, 2016	2,459		$	6.00

Schedule of Stock-based Compensation Expense

Stock-based compensation expenses for the three months ended March 31, 2016 and 2015 were as follows (in thousands):



	Three Months Ended
	March 31, 2016		March 31, 2015
Cost of revenue	$	265	$	188
Research and development	435		574
Sales and marketing	434		524
General and administrative	860		949
Total stock-based compensation	$	1,994	$	2,235

As of March 31, 2016, unrecognized stock-based compensation expenses by award type, net of estimated forfeitures, and their expected weighted-average recognition periods are summarized in the following table (in thousands, except years).



	Stock Option		RSU		ESPP
Unrecognized stock-based compensation expense	$	7,495	$	11,704	$	67
Weighted-average amortization period	2.5 years		3.3 years		0.1 years

Schedule of Valuation Assumptions, Stock Option

The weighted-average assumptions used to value stock options granted during the three months ended March 31, 2016 and 2015 were as follows:



Stock Options	Three Months Ended
	March 31, 2016	March 31, 2015
Expected term (years)	6.0	*
Volatility	48%	*
Risk-free interest rate	1.5%	*
Dividend yield	—	*


* No stock options were granted during the three months ended March 31, 2015.