Stock-Based Compensation

We maintain a stock-based compensation program intended to attract, retain and provide incentives for talented employees and directors and align stockholder and employee interests. Currently, we grant options and restricted stock units ("RSUs") from the 2010 Equity Compensation Plan (“2010 ECP”) and 2017 Equity Compensation Plan ("2017 ECP"). Option and RSUs vesting periods are generally up to three years and/or achieving certain financial targets.

Compensation Expense

For the three and six months ended June 30, 2019, we recorded stock-based compensation expense for all equity incentive plans of $49,823 and $146,693, respectively. For the three and six months ended June 30, 2018, we recorded stock-based compensation expense for all equity incentive plans of $289,950 and $667,797. Total compensation cost not yet recognized at June 30, 2019 was $866,528 to be recognized over a weighted-average recognition period of 1.44 years.

The following table summarizes the stock grants outstanding under our 2005 Long-Term Incentive Plan ("2005 LTIP"), the 2010 ECP and the 2017 ECP for the three months ended June 30, 2019:



	Options Outstanding	RSUs Outstanding	Options and RSUs Exercised	Available Shares	Total
2017 ECP	—	846,273	41,664	1,412,063	2,300,000
2010 ECP	250,498	542,894	3,635,701	652,925	5,082,018
2005 LTIP (*)	13,748	—	950,085	—	963,833
Total	264,246	1,389,167	4,627,450	2,064,988	8,345,851

(*) Expired June 2015

The following table summarizes the activities of stock option awards under the 2005 LTIP and the 2010 ECP as of June 30, 2019:



	Shares Subject to Options Outstanding
	Number of Shares	Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (in years)	Aggregate Intrinsic Value
Balance as of December 31, 2018	264,246	$	2.84	2.7	$	2,019
Stock options exercised	—	$	—	—	—
Balance as of June 30, 2019	264,246	$	2.84	2.7	$	2,019
Stock options exercisable as of June 30, 2019	264,246	$	2.84	2.7	$	2,019

The following table summarizes the activities for our unvested RSUs for the three months ended June 30, 2019:



	Unvested RSUs
	Number of Shares	Weighted Average Grant Date Fair Value
Unvested as of December 31, 2018	1,571,864	$	0.79
Granted	112,773	$	1.40
Vested	254,782	$	0.86
Forfeited	40,688	$	0.93
Unvested as of June 30, 2019	1,389,167	$	0.83