EMPLOYEE STOCK PLANS

As of December 31, 2015, we had approximately 4.1 million shares available for future grant under our 2012 Equity Incentive Plan (the "2012 Plan").

On May 28, 2015, the stockholders approved an amendment to our 2012 Plan: (i) increasing the number of shares reserved for issuance under the 2012 Plan by an additional 2.5 million shares, bringing the total shares reserved thereunder, to 19.5 million shares; and (ii) removing the 1.75 share accounting ratio applicable to stock awards and restricted stock units.

Stock Options

Options to purchase common stock granted under the 2012 Plan generally have terms not exceeding seven years. Options to purchase stock under our equity incentive plans are granted at exercise prices that are at least 100 percent of the fair market value of our common stock on the date of grant. Generally, 25 percent of the options vest on the first anniversary of the vesting commencement date, and the remaining options vest 1/36 per month for the next 36 months thereafter. In December 2013, our Board of Directors approved the adoption of monthly vesting of stock options for employees with a minimum of one year of service.

We granted 0.7 million, 0.7 million and 1.6 million stock options during 2015, 2014 and 2013, respectively, with an estimated total grant date fair value of $1.2 million, $0.9 million and $1.4 million, respectively. We settle employee stock option exercises with newly issued common shares.

The following table summarizes the stock option activity under all of our equity incentive plans for the years ended December 31, 2015 and 2014:



	Number of Shares		Weighted- Average Exercise Price Per Share		Weighted Average Remaining Contractual Life	Aggregate Intrinsic Value
	(thousands)				(years)	(thousands)
Outstanding at December 31, 2013	4,993		$	2.18	4.9	$	5,281
Granted	746		2.42
Exercised	(486	)	1.03
Forfeited or expired	(333	)	7.01
Outstanding at December 31, 2014	4,920		$	2.01	4.2	$	7,513
Granted	716		3.37
Exercised	(1,017	)	1.91
Forfeited or expired	(447	)	4.16
Outstanding at December 31, 2015	4,172		$	2.04	4.1	$	6,254
Vested and expected to vest at December 31, 2015	3,928		$	2.00	4.0	$	6,059
Exercisable at December 31, 2015	2,785		$	1.80	3.5	$	4,818

The aggregate intrinsic value represents the pre-tax differences between the exercise price of stock options and the quoted market price of our stock on December 31, 2015 for all in-the-money stock options.

The following table provides supplemental information pertaining to our stock options for the years ended December 31 (in thousands, except weighted-average fair values):



	2015		2014		2013
Weighted-average fair value of options granted	$	1.70	$	1.24	$	0.87
Intrinsic value of options exercised	$	2,449	$	685	$	386
Cash received from options exercised	$	1,940	$	502	$	445

Restricted Stock Units

The 2012 Plan provides for grants of time-based and performance-based restricted stock units ("RSUs"). As of December 31, 2015, we only had time-based RSUs outstanding.

Historically, 25 percent of the time-based RSUs vest on each anniversary of the vesting commencement date or date of grant. In December 2013, our Board of Directors approved a quarterly vesting schedule for RSUs. On occasion, we grant time-based RSUs for varying purposes with different vesting schedules. Time-based RSUs granted under the 2012 Plan prior to May 28, 2015 are counted against the total number of shares of common stock available for grant at a ratio of 1.75 shares of common stock for every one share of common stock subject thereto, and RSUs granted on or after May 28, 2015 are counted against the total number of shares of common stock available for grant at a ratio of 1.00 share of common stock for every one share of common stock subject thereto.

The following table summarizes RSU activity under all of our equity incentive plans for the years ended December 31, 2015 and 2014:



	Number of Shares		Weighted Average Grant Date Fair Value
	(thousands)
Outstanding at December 31, 2013	429		$	1.45
Granted	697		2.42
Released	(232	)	1.99
Forfeited or Expired	(17	)	2.49
Outstanding at December 31, 2014	877		$	2.06
Granted	994		3.33
Released	(462	)	2.57
Forfeited or Expired	(120	)	2.86
Outstanding at December 31, 2015	1,289		$	2.78

Employee Stock Purchase Plan

Our 1994 Employee Stock Purchase Plan (“1994 Plan”) was originally adopted by the Board of Directors and approved by the stockholders in 1994. In May 2014, the Board of Directors amended and restated the 1994 Plan, which was then approved by the stockholders, extending the term of the 1994 Plan by an additional ten years, with an expiration date of May 19, 2024.

Our 1994 Plan is a non-compensatory employee stock purchase plan ("ESPP"), which allows each eligible employee to withhold up to 15 percent of gross compensation over semi-annual six month ESPP periods to purchase shares of our common stock, limited to 2,000 shares per ESPP period through December 2013, and 4,000 shares per ESPP period thereafter. Under the ESPP, employees purchase stock at a price equal to 90 percent of the fair market value (generally the closing price of our common stock) on the last trading day prior to the end of the six month ESPP offering period.

We reserved approximately 6.2 million shares of common stock for issuance under the ESPP, of which 2.4 million shares were available for issuance as of December 31, 2015. We issued approximately 0.1 million shares under the ESPP in each of the years ended December 31, 2015, 2014 and 2013, with average purchase prices of $2.99, $2.17 and $2.09, respectively.

Employee Savings Plan

We have an employee retirement and savings plan (the "ESP"), which qualifies under section 401(k) of the Internal Revenue Code. All full-time employees of eligible age (over 21 years old) can participate in the ESP and can contribute up to an amount allowed by the applicable Internal Revenue Service guidelines. At our discretion, we can make matching contributions to the ESP equal to a percentage of the participants' contributions. For the years ended December 31, 2015, 2014 and 2013, we recorded 401(k) match contributions in the amount of $0.2 million, $0.2 million and $0.1 million, respectively.