Stock-Based Compensation and Employee Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2015

Stock-based compensation expense for the years ended December 31 was as follows (in thousands):


	2015		2014		2013
Cost of revenues	$	230	$	183	$	163
Selling, general and administrative		1,246		1,176		1,942
Research and development		306		275		345

Total stock-based compensation	$	1,782	$	1,634	$	2,450

Weighted-Average Assumptions for Fair Value for Stock Options

The fair value for options awarded for the years shown below was estimated at the date of grant using the Black-Scholes option pricing model with the following weighted-average assumptions:


	Non Performance- based Stock Options
Vicor:	2015			2014			2013
Risk-free interest rate		2.0	%		2.2	%		1.2	%
Expected dividend yield		—			—			—
Expected volatility		51	%		52	%		39	%
Expected lives (years)		7.2			6.6			4.9

VI Chip:	2015			2014			2013
Risk-free interest rate		2.1	%		2.3	%		1.6	%
Expected dividend yield		—			—			—
Expected volatility		37	%		41	%		48	%
Expected lives (years)		6.5			6.5			6.5

Picor:	2015			2014			2013
Risk-free interest rate		1.9	%		2.2	%		1.2	%
Expected dividend yield		—			—			—
Expected volatility		41	%		42	%		49	%
Expected lives (years)		6.5			6.5			6.5

Vicor Plan [Member]

Stock-Based Compensation Expense

A summary of the activity under Vicor’s stock option plans as of December 31, 2015 and changes during the year then ended, is presented below (in thousands except for share and weighted-average data):


	Options Outstanding			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Life in Years		Aggregate Intrinsic Value
Outstanding on December 31, 2014		1,895,675		$	8.07
Granted		194,561		$	12.51
Forfeited and expired		(117,085	)	$	9.30
Exercised		(125,084	)	$	6.44

Outstanding on December 31, 2015		1,848,067		$	8.57		7.64	$	2,637

Exercisable on December 31, 2015		565,861		$	7.24		7.25	$	1,269

Vested or expected to vest as of December 31, 2015 (1)		1,778,075		$	8.51		7.64	$	2,580

(1)	In addition to the vested options, the Company expects a portion of the unvested options to vest at some point in the future. The number of options expected to vest is calculated by applying an estimated forfeiture rate to the unvested options.

Picor Plan [Member]

Stock-Based Compensation Expense

A summary of the activity under the 2001 Picor Plan as of December 31, 2015 and changes during the year then ended, is presented below (in thousands except for share and weighted-average data):


	Options Outstanding			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Life in Years		Aggregate Intrinsic Value
Outstanding on December 31, 2014		9,870,067		$	0.62
Granted		82,000		$	1.09
Forfeited and expired		(8,000	)	$	0.75
Exercised		(219,000	)	$	0.76

Outstanding on December 31, 2015		9,725,067		$	0.62		5.01	$	4,520

Exercisable on December 31, 2015		8,053,490		$	0.64		4.48	$	3,594

Vested or expected to vest as of December 31, 2015 (1)		9,668,334		$	0.62		4.99	$	4,488

(1)	In addition to the vested options, the Company expects a portion of the unvested options to vest at some point in the future. Options expected to vest is calculated by applying an estimated forfeiture rate to the unvested options.

Vi Chip Plan [Member]

Stock-Based Compensation Expense

A summary of the activity under the 2007 VI Chip Plan as of December 31, 2015 and changes during the year then ended, is presented below (in thousands except for share and weighted-average data):


	Options Outstanding			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Life in Years		Aggregate Intrinsic Value
Outstanding on December 31, 2014		10,715,000		$	1.00
Granted		82,500		$	1.00
Forfeited and expired		(699,000	)	$	1.00
Exercised		(1,000	)	$	1.00

Outstanding on December 31, 2015 (1)		10,097,500		$	1.00		2.87	$	—

Exercisable on December 31, 2015		7,042,600		$	1.00		1.75	$	—

Vested or expected to vest as of December 31, 2015 (2)		9,821,129		$	1.00		2.80	$	—

(1)	Of the total VI Chip options outstanding on December 31, 2015, 5,500,000 options had been granted to Dr. Vinciarelli, the Company’s Chief Executive Officer.

(2)	In addition to the vested options, the Company expects a portion of the unvested options to vest at some point in the future. Options expected to vest is calculated by applying an estimated forfeiture rate to the unvested options.