NOTE 7: COMMON STOCK AND STOCK-BASED COMPENSATION PLANS

The Company grants stock options and stock appreciation rights (“SARs”) capped with a ceiling to employees and stock options to non-employee directors of the Company and its subsidiaries and provides the right to purchase common stock pursuant to the Company’s 2002 employee stock purchase plan to employees of the Company and its subsidiaries. The SAR unit confers the holder the right to stock appreciation over a preset price of the Company’s common stock during a specified period of time. When the unit is exercised, the appreciation amount is paid through the issuance of shares of the Company’s common stock. The ceiling limits the maximum income for each SAR unit. SARs are considered an equity instrument as it is a net share settled award capped with a ceiling (400% for SAR grants). The options and SARs granted under the Company’s stock incentive plans have been granted at the fair market value of the Company’s common stock on the grant date. Options and SARs granted to employees under stock incentive plans vest at a rate of 25% of the shares underlying the option after one year and the remaining shares vest in equal portions over the following 36 months, such that all shares are vested after four years. Options granted to non-employee directors vest 25% of the shares underlying the option on each anniversary of the option grant. A summary of the Company’s stock option and SARs activities and related information for the nine months ended September 30, 2017, are as follows:


	Number of options and SAR units (1)			Weighted average exercise price		Weighted average remaining contractual term		Aggregate intrinsic-value
Outstanding as of December 31, 2016		1,455,908		$	19.76
Granted		—			—
Exercised		(588,972	)		19.74
Forfeited or expired		(14,349	)		17.56

Outstanding as of September 30, 2017 (2)		852,587		$	19.81		5.2	$	19,598

Exercisable as of September 30, 2017 (3)		604,327		$	19.18		4.7	$	14,271

(1)	The SAR units are convertible for a maximum number of shares of the Company’s common stock equal to 75% of the SAR units subject to the grant.

(2)	Due to the ceiling imposed on the SAR grants, the outstanding amount equals a maximum of 775,403 shares of the Company’s common stock issuable upon exercise.

(3)	Due to the ceiling imposed on the SAR grants, the exercisable amount equals a maximum of 551,645 shares of the Company’s common stock issuable upon exercise.

As of September 30, 2017, there was $750 of unrecognized compensation expense related to unvested stock options and SARs. This amount is expected to be recognized over a weighted-average period of 1.4 years.

Starting in the second quarter of 2015, the Company granted to employees, including executive officers, and non-employee directors, restricted stock units (“RSUs”) under the Company’s 2011 Stock Incentive Plan. A RSU award is an agreement to issue shares of the Company’s common stock at the time the award or a portion thereof vests. RSUs granted to employees generally vest in three equal annual installments starting on the first anniversary of the grant date. RSUs granted to non-employee directors generally vest in full on the first anniversary of the grant date. The fair value of each RSU is the market value as determined by the closing price of the common stock on the day of grant. The Company recognizes compensation expenses for the value of its RSU awards, based on the straight-line method over the requisite service period of each of the awards. A summary of the Company’s RSU activities and related information for the nine months ended September 30, 2017, are as follows:


	Number of RSUs			Weighted Average Grant-Date Fair Value
Unvested as of December 31, 2016		505,142		$	21.59
Granted		269,497			36.84
Vested		(193,399	)		21.46
Forfeited or expired		(26,374	)		26.01

Unvested as of September 30, 2017		554,866		$	28.84

As of September 30, 2017, there was $12,126 of unrecognized compensation expense related to unvested RSUs. This amount is expected to be recognized over a weighted-average period of 1.5 years.

The following table shows the total equity-based compensation expense included in the interim condensed consolidated statements of income:


	Nine months ended September 30,				Three months ended September 30,
	2017		2016		2017		2016
	(unaudited)		(unaudited)		(unaudited)		(unaudited)
Cost of revenue	$	330	$	179	$	125	$	65
Research and development, net		2,834		2,162		991		741
Sales and marketing		1,040		681		381		179
General and administrative		2,142		1,626		722		580

Total equity-based compensation expense	$	6,346	$	4,648	$	2,219	$	1,565

The fair value for rights to purchase shares of common stock under the Company’s employee stock purchase plan was estimated on the date of grant using the following assumptions:


	Nine months ended September 30,						Three months ended September 30,
	2017			2016			2017			2016
	(unaudited)			(unaudited)			(unaudited)			(unaudited)
Expected dividend yield		0	%		0	%		0	%		0	%
Expected volatility		28%-46	%		29%-57	%		28%-43	%		29%-48	%
Risk-free interest rate		0.5%-1.1	%		0.3%-0.5	%		0.6%-1.1	%		0.4%-0.5	%
Expected forfeiture		0	%		0	%		0	%		0	%
Contractual term of up to		24 months			24 months			24 months			24 months