13. Stock Option and Compensation Plans

The Company adopted its 2007 Stock Incentive Plan (the "2007 Plan") for employees and consultants for the purpose of advancing the interests of the Company stockholders by enhancing its ability to attract, retain and motivate persons who are expected to make important contributions to the Company. The 2007 Plan provided for the granting of stock option awards, restricted stock awards, and other stock-based and cash-based awards. Following the effectiveness of the 2013 Stock Incentive Plan described below in connection with the closing of the Company's initial public offering, the Company is no longer granting additional awards under the 2007 Plan.

During the year ended December 31, 2013, the Company's Board of Directors and stockholders increased the number of shares authorized under the 2007 Plan by 1,878,343 shares. The Company's Board of Directors also adopted and the Company's stockholders also approved the 2013 stock incentive plan (the "2013 Plan"), which became effective immediately prior to the closing of the Company's initial public offering. The 2013 Plan provides for the grant of incentive stock options, nonstatutory stock options, stock appreciation rights, restricted stock awards, restricted stock unit awards, and other stock-based awards. Upon effectiveness of the 2013 Plan, the number of shares of the Company's common stock that were reserved for issuance under the 2013 Plan was the sum of (1) such number of shares (up to approximately 3,359,641 shares) as is equal to the sum of 739,317 shares (the number of shares of the common stock then available for issuance under the 2007 Plan), and such number of shares of the Company's common stock that are subject to outstanding awards under the 2007 Plan that expire, terminate or are otherwise surrendered, canceled, forfeited or repurchased by the Company at their original issuance price pursuant to a contractual repurchase right plus (2) an annual increase, to be added the first day of each fiscal year, beginning with the fiscal year ending December 31, 2014 and continuing until, and including, the fiscal year ending December 31, 2023, equal to the lowest of 2,542,372 shares of the Company's common stock, 4% of the number of shares of the Company's common stock outstanding on the first day of the fiscal year and an amount determined by the Company's board of directors. The Company's employees, officers, directors, consultants and advisors are eligible to receive awards under the 2013 Plan. However, incentive stock options may only be granted to employees of the Company.

As of December 31, 2013, the Company had approximately 2,708,000 stock options outstanding under the 2013 Plan and approximately 503,000 shares available for grant under the 2013 Plan. In connection with the evergreen provisions of the 2013 Plan, the number of shares available for issuance under the 2013 Plan was increased by approximately 1,257,000, effective as of January 1, 2014.

Cash proceeds from, and the aggregate intrinsic value of, stock options exercised during the years ended December 31, 2013, 2012 and 2011, respectively, were as follows:

	Year ended December, 31

	2013		2012		2011
Cash proceeds from options exercised	$	93	$	2	$	4
Aggregate intrinsic value of options exercised	$	4,545	$	28	$	36

A summary of the stock option activity, weighted average exercise prices, options outstanding and exercisable as of December 31, 2013 is as follows:

	For the Year ended December 31,

	2013					2012					2011
	Common Stock Options			Weighted Average Exercise Price		Common Stock Options			Weighted Average Exercise Price		Common Stock Options			Weighted Average Exercise Price
Outstanding at beginning of year:		1,344		$	1.65		1,113		$	1.30		953		$	1.20
Granted		1,583		$	14.82		250		$	3.12		184		$	1.65
Exercised		(151	)	$	0.61		(19	)	$	0.12		(24	)	$	0.17
Expired or forfeited		(68	)	$	1.53		—			—		—			—


Outstanding at end of year:		2,708		$	9.41		1,344		$	1.65		1,113		$	1.30

	Year ended December 31,

	2013		2012		2011
Options exercisable at end of year		984		823		561
Weighted average grant date fair value (per share) of options granted during the period	$	10.48	$	1.65	$	1.18

			As of December 31, 2013

			Options Outstanding				Options Exercisable
Range of Exercise Prices	Total Options Outstanding		Weighted Average Remaining Life (Years)		Weighted Average Exercise Price		Number Exercisable		Weighted Average Exercise Price
$0.12 - $10.03		1,800		7.8	$	4.89		969	$	2.50
$10.04 - $20.00		604		9.5	$	13.37		10	$	13.22
$20.01 - $33.27		304		9.8	$	28.34		5	$	32.58


		2,708						984




Aggregate Intrinsic Value	$	62,185					$	29,107

In connection with stock option awards granted to employees, the Company recognized share-based compensation expense approximately $2.2 million, $0.5 million, and $0.2 million, for the years ended December 31, 2013, 2012, and 2011, respectively. As of December 31, 2013, there was approximately $14.6 million of unrecognized compensation costs, net of estimated forfeitures, related to stock option awards to employees, which are expected to be recognized over a remaining weighted average period of 3.3 years.

In connection with stock options awards granted to consultants, the Company recognized approximately $0.7 million, $0.1 million and $0.1 million in share-based compensation expense during the years ended December 31, 2013, 2012 and 2011, respectively. As of December 31, 2013, there were approximately $1.9 million of unrecognized compensation costs, net of estimated forfeitures, related to stock option award granted to consultants which are expected to be recognized over a remaining weighted average period of 3.0 years.