STOCK-BASED COMPENSATION (Tables)

6 Months Ended

Jun. 30, 2019

STOCK-BASED COMPENSATION

Schedule of ESPP expense incurred under the 2016 Employee Stock Purchase Plan and stock-based compensation expense incurred under the 2008 Plan

The following table summarizes ESPP expense incurred under the 2016 Employee Stock Purchase Plan and included in our accompanying unaudited interim condensed consolidated statements of operations:

	Three Months Ended June 30,				Six Months Ended June 30,
(in thousands)	2019		2018		2019		2018
Cost of sales	$	3	$	2	$	6	$	4
Research and development		4		2		9		3
Selling, general, and adminstrative		23		14		45		28
	$	30	$	18	$	60	$	35

The following table susmmarizes stock-based compensation expense incurred under the 2008 Plan and included in our accompanying unaudited interim condensed consolidated statements of operations: 

	Three Months Ended June 30,				Six Months Ended June 30,
(in thousands)	2019		2018		2019		2018
Cost of sales	$	28	$	24	$	49	$	42
Research and development		219		220		332		380
Selling, general, and adminstrative		2,316		1,520		3,862		2,702
	$	2,563	$	1,764	$	4,243	$	3,124

Summary of Stock option and restricted stock activity

A summary of stock option and restricted stock activity under the 2008 Plan during the six months ended June 30, 2019 and 2018 is presented below:

(in thousands)	Options	RSAs
Outstanding December 31, 2017	767	86
Granted	151	65
Options Exercised/RSAs Vested	(111)	(33)	(1)
Forfeited	(16)	—
Outstanding June 30, 2018	1,582	236
Outstanding December 31, 2018	759	117
Granted	160	122	(2)
Options Exercised/RSAs Vested	(114)	(42)
Forfeited	(18)	(2)
Expired	(1)	—
Outstanding June 30, 2019	786	195