Restricted Stock Units

6 Months Ended

Jun. 30, 2016

Restricted Stock Units

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Restricted Stock Units

Restricted Stock Units

A summary of restricted stock units granted, vested, forfeited and unvested outstanding as of, and changes made during, the six months ended June 30, 2016, is presented below (shares in thousands):

	Restricted Stock Units		Weighted Average Grant Price
Unvested restricted stock units outstanding, December 31, 2015	2,164		$	1.02
Granted	1,677		0.49
Vested	(387	)	0.92
Forfeited	(246	)	0.91
Unvested restricted stock units outstanding, June 30, 2016	3,208		$	0.76

As of June 30, 2016, 387,000 vested restricted stock units remain outstanding as shares of common stock have not yet been delivered for these units in accordance with the terms of the restricted stock units.

Stock-based compensation expense related to restricted stock units is allocated as follows for the three and six months ended June 30, 2016 and 2015 (in thousands):

	Three Months Ended					Six Months Ended
	June 30,					June 30,
	2016			2015		2016		2015
Cost of revenue	$	9		$	3	$	17	$	5
Research and development	10			3		19		5
Sales and marketing	(3		)	2		1		3
General and administrative	84			80		161		145
	$	100		$	88	$	198	$	158

Certain restricted stock unit awards have performance-based vesting provisions and are subject to forfeiture, in whole or in part, if these performance conditions are not achieved. Management assesses, on an ongoing basis, the probability of whether the performance criteria will be achieved and, once it is deemed probable, compensation expense is recognized over the relevant performance period. For those awards not subject to performance criteria, the cost of the restricted stock unit awards is expensed, which is determined to be the fair market value of the shares at the date of grant, on a straight-line basis over the vesting period.

The remaining unrecognized stock-based compensation expense for restricted stock units as of June 30, 2016 was $2,194,000. Of this amount $655,000 relates to time-based awards with a remaining weighted average period of 1.15 years. The remaining $1,539,000 of unrecognized stock-based compensation expense relates to performance-based awards for which expense will be recognized upon the Company achieving defined revenue targets and other financial goals over fiscal years 2016, 2017 and 2018.