Note 9: Share-Based Compensation

Total share-based compensation expense related to the Company's stock options, RSUs, stock grant awards and ESPP were recorded within the Consolidated Statements of Operations and Comprehensive Income as follows (in millions):



	Quarter Ended
	March 30, 2018		March 31, 2017
Cost of revenues	$	1.6	$	1.5
Research and development	3.2		2.9
Selling and marketing	3.2		2.8
General and administrative	10.4		7.9
Share-based compensation expense before income taxes	$	18.4	$	15.1
Related income tax benefits ⁽¹⁾	3.9		5.3
Share-based compensation expense, net of taxes	$	14.5	$	9.8


⁽¹⁾	Tax benefit calculated using the federal statutory rate of 21% and 35% for the quarters ended March 30, 2018 and March 31, 2017, respectively.

At March 30, 2018, total unrecognized estimated share-based compensation expense, net of estimated forfeitures, related to non-vested stock options was less than $0.1 million, which is expected to be recognized over a weighted-average period of 4 months. At March 30, 2018, total unrecognized share-based compensation expense, net of estimated forfeitures, related to non-vested RSUs with time-based service conditions and performance-based vesting criteria was $130.9 million, which is expected to be recognized over a weighted-average period of 1.98 years. The total intrinsic value of stock options exercised during the quarter ended March 30, 2018 was $9.4 million. The Company received cash of $3.6 million for the quarter ended March 30, 2018 from the exercise of stock options. Upon option exercise, vesting of RSUs, stock grant awards or completion of a purchase under the ESPP, the Company issues new shares of common stock.

Share-based compensation expense is based on awards that are ultimately expected to vest. Forfeitures are estimated at the time of grant and revised, if necessary, in subsequent periods if actual forfeitures differ from those estimates. The annualized pre-vesting forfeiture rate for stock options was estimated to be 11% during the quarters ended March 30, 2018 and March 31, 2017. The annualized pre-vesting forfeiture rate for RSUs was estimated to be 5% during the quarters ended March 30, 2018 and March 31, 2017.

Shares Available

As of March 30, 2018, there was an aggregate of 34.9 million shares of common stock available for grant under the Amended and Restated SIP and 8.0 million shares available for issuance under the ESPP. As of December 31, 2017, there was an aggregate of 39.0 million shares of common stock available for grant under the Company's Amended and Restated SIP and 8.0 million shares available for issuance under the ESPP.

Stock Options

A summary of stock option transactions for all stock option plans is as follows (in millions, except per share and contractual term data):



	Quarter Ended March 30, 2018
	Number of Shares		Weighted-Average Exercise Price Per Share		Weighted-Average Remaining Contractual Term (in years)	Aggregate Intrinsic Value (In-The-Money)
Outstanding at December 31, 2017	1.1		$	6.95
Granted	—		—
Exercised	(0.6	)	6.79
Canceled	—		—
Outstanding at March 30, 2018	0.5		$	7.11	1.18	$	9.2

Exercisable at March 30, 2018	0.5		$	7.11	1.18	$	9.2

All outstanding options had exercise prices below $24.46 per share, the closing price of the Company's common stock at March 30, 2018.

Restricted Stock Units

RSUs generally vest over three years with service-based requirements or performance-based requirements or a combination of service-based and performance-based requirements and are payable in shares of the Company's common stock upon vesting. A summary of the RSU transactions for the quarter ended March 30, 2018 is as follows (in millions, except per share data):



	Number of Shares		Weighted-Average Grant Date Fair Value Per Share
Non-vested RSUs at December 31, 2017	9.8		$	12.63
Granted	2.7		24.43
Released	(2.6	)	12.18
Forfeited	(0.1	)	13.49
Non-vested RSUs at March 30, 2018	9.8		15.94