Benefit Plans

Stock Plans

The Company had 316.4 million shares reserved for future issuance under its stock plans as of December 31, 2016. RSUs granted generally vest over four years, based on continued employment, and are settled upon vesting in shares of the Company’s common stock on a one-for-one basis. Each share issued with respect to RSUs granted under the Company’s stock plans reduces the number of shares available for grant under the plan by two shares. RSUs cancelled and shares withheld to satisfy tax withholding obligations increase the number of shares available for grant under the plans utilizing a factor of two times the number of RSUs cancelled or shares withheld.

Rule 10b5-1 Trading Plans

During the three months ended December 31, 2016, Section 16 officers Timothy D. Cook, Luca Maestri, Daniel Riccio, Philip Schiller and Jeffrey Williams had equity trading plans in place in accordance with Rule 10b5-1(c)(1) under the Exchange Act. An equity trading plan is a written document that pre-establishes the amounts, prices and dates (or formula for determining the amounts, prices and dates) of future purchases or sales of the Company’s stock, including shares acquired pursuant to the Company’s employee and director equity plans.

Restricted Stock Units

A summary of the Company’s RSU activity and related information for the three months ended December 31, 2016 is as follows:



	Number of RSUs (in thousands)		Weighted-Average Grant Date Fair Value Per Share		Aggregate Fair Value (in millions)
Balance at September 24, 2016	99,089		$	97.54
RSUs granted	42,882		$	117.95
RSUs vested	(18,535	)	$	92.65
RSUs cancelled	(1,577	)	$	105.01
Balance at December 31, 2016	121,859		$	105.37	$	14,114

RSUs that vested during the three months ended December 31, 2016 and December 26, 2015 had fair values of $2.2 billion and $2.0 billion, respectively, as of the vesting date.

Share-Based Compensation

The following table shows a summary of the share-based compensation expense included in the Condensed Consolidated Statements of Operations for the three months ended December 31, 2016 and December 26, 2015 (in millions):



	Three Months Ended
	December 31, 2016		December 26, 2015
Cost of sales	$	229	$	204
Research and development	589		466
Selling, general and administrative	438		408
Total share-based compensation expense	$	1,256	$	1,078

The income tax benefit related to share-based compensation expense was $465 million and $413 million for the three months ended December 31, 2016 and December 26, 2015, respectively. As of December 31, 2016, the total unrecognized compensation cost related to outstanding RSUs, restricted stock and stock options was $11.0 billion, which the Company expects to recognize over a weighted-average period of 2.9 years.