STOCK-BASED COMPENSATION

The Company's 1999 Omnibus Plan, as amended and restated effective June 6, 2013, (the "1999 Plan") is the primary stock compensation plan from which broad-based employee equity awards may be made. As of December 31, 2015, there were 2,425,519 shares of common stock available for future grant under the 1999 Plan. In addition, in connection with the acquisition of KAYAK in May 2013, Buuteeq, Inc. in June 2014, OpenTable in July 2014 and Rocket Travel, Inc. in February 2015, the Company assumed the KAYAK Software Corporation 2012 Equity Incentive Plan (the "KAYAK Plan"), the Buuteeq, Inc. Amended and Restated 2010 Stock Plan (the "Buuteeq Plan"), the OpenTable, Inc. 2009 Equity Incentive Award Plan (the "OpenTable Plan") and the Rocket Travel, Inc. 2012 Stock Incentive Plan (the “Rocketmiles Plan”). As of December 31, 2015, there were 145,392 shares of common stock available for future grant under the OpenTable Plan.

Stock-based compensation issued under the plans generally consists of restricted stock units, performance share units and stock options. Stock-based compensation is recognized in the financial statements based upon fair value. Fair value is recognized as expense on a straight-line basis, net of estimated forfeitures, over the employee's requisite service period. The fair value of restricted stock units and performance share units is determined based on the number of units granted and the quoted price of the Company's common stock as of the grant date. Stock-based compensation related to performance share units reflects the estimated probable outcome at the end of the performance period. The fair value of the employee stock options assumed in acquisitions was determined using the Black-Scholes model and the market value of the Company's common stock at their respective acquisition dates. Stock options granted to employees generally have a term of 10 years. Restricted stock units and performance share units generally vest over periods from 1 to 4 years. The Company issues new shares of common stock upon the issuance of restricted stock, the exercise of stock options and the vesting of restricted stock units and performance share units.

Stock-based compensation included in personnel expenses in the Consolidated Statements of Operations was approximately $247.4 million, $186.4 million and $140.5 million for the years ended December 31, 2015, 2014 and 2013, respectively. Stock-based compensation for the years ended December 31, 2015, 2014 and 2013 includes charges amounting to $22.6 million, $20.6 million and $24.1 million, respectively, representing the impact of adjusting the estimated probable outcome at the end of the performance period for outstanding unvested performance share units. Included in the stock-based compensation are approximately $2.6 million, $2.3 million, and $2.1 million for the years ended December 31, 2015, 2014, and 2013, respectively, for grants to non-employee directors. The related tax benefit for stock-based compensation is $52.9 million, $38.4 million and $18.5 million for the years ended December 31, 2015, 2014 and 2013, respectively.

Restricted Stock Units and Performance Share Units

The following table summarizes the activity of restricted stock units and performance share units ("share-based awards") during the years ended December 31, 2013, 2014 and 2015:



Share-Based Awards	Shares		Weighted Average Grant Date Fair Value

Unvested at December 31, 2012	540,128			$	389.21

Granted	162,341			$	730.47
Vested	(258,198	)		$	242.63
Performance Shares Adjustment	101,490			$	681.13
Forfeited/Canceled	(11,442	)		$	579.71
Unvested at December 31, 2013	534,319			$	615.10

Granted	128,484			$	1,308.13
Assumed in an acquisition	43,993			$	1,238.68
Vested	(195,730	)		$	492.22
Performance Shares Adjustment	68,499			$	1,085.94
Forfeited/Canceled	(9,250	)		$	972.19
Unvested at December 31, 2014	570,315			$	912.26

Granted	198,141			$	1,226.41
Vested	(161,862	)		$	757.66
Performance Shares Adjustment	64,328			$	1,238.30
Forfeited/Canceled	(33,665	)		$	1,151.70
Unvested at December 31, 2015	637,257			$	1,070.10

Share-based awards granted by the Company during the years ended December 31, 2015, 2014 and 2013 had aggregate grant date fair values of approximately $243.0 million, $168.1 million and $118.6 million, respectively. Share-based awards that vested during the years ended December 31, 2015, 2014, and 2013 had grant date fair values of $122.6 million, $96.3 million and $62.6 million, respectively.

As of December 31, 2015, there was $336.5 million of total future compensation cost related to unvested share-based awards to be recognized over a weighted-average period of 1.9 years.

During the year ended December 31, 2015, the Company made broad-based grants of 90,518 restricted stock units that generally vest after three years, subject to certain exceptions for terminations other than for "cause," for "good reason" or on account of death or disability. These share-based awards had a total grant date fair value of $109.8 million based on a weighted-average grant date fair value per share of $1,213.18.

In addition, during the year ended December 31, 2015, the Company granted 107,623 performance share units to executives and certain other employees. The performance share units had a total grant date fair value of $133.2 million based upon a weighted-average grant date fair value per share of $1,237.53. The performance share units are payable in shares of the Company's common stock upon vesting. Subject to certain exceptions for terminations other than for "cause," for "good reason" or on account of death or disability, recipients of these performance share units generally must continue their service through the requisite service period in order to receive any shares. Stock-based compensation related to performance share units reflects the estimated probable outcome at the end of the performance period. The actual number of shares to be issued on the vesting date will be determined upon completion of the performance period, which, for most of these performance share units, ends December 31, 2017, assuming there is no accelerated vesting for, among other things, a termination of employment under certain circumstances. As of December 31, 2015, the estimated number of probable shares to be issued is a total of 164,857 shares. If the maximum performance thresholds are met at the end of the performance period, a maximum number of 254,643 total shares could be issued. If the minimum performance thresholds are not met, 51,621 shares would be issued at the end of the performance period.

2014 Performance Share Units

During the year ended December 31, 2014, the Company granted 72,277 performance share units with a grant date fair value of $96.1 million, based on a weighted-average grant date fair value per share of $1,329.11. The actual number of shares to be issued will be determined upon completion of the performance period which generally ends December 31, 2016.

At December 31, 2015, there were 63,484 unvested 2014 performance share units outstanding, net of performance share units that were forfeited or vested since the grant date. As of December 31, 2015, the number of shares estimated to be issued pursuant to these performance share units at the end of the performance period is a total of 104,241 shares. If the maximum thresholds are met at the end of the performance period, a maximum of 127,732 total shares could be issued pursuant to these performance share units. If the minimum performance thresholds are not met, 43,291 shares would be issued at the end of the performance period.

2013 Performance Share Units

During the year ended December 31, 2013, the Company granted 104,865 performance share units with a grant date fair value of $74.4 million, based on a weighted-average grant date fair value per share of $709.74. The actual number of shares to be issued will be determined based upon completion of the performance period which ended December 31, 2015.

At December 31, 2015, there were 97,296 unvested 2013 performance share units outstanding, net of performance share units that were forfeited or vested since the grant date. As of December 31, 2015, the total number of shares expected to be issued pursuant to these performance share units on the March 4, 2016 vesting date is 186,020 shares.

Stock Options

The following table summarizes the activity for the stock options during the years ended December 31, 2013, 2014 and 2015:



Employee Stock Options	Number of Shares		Weighted Average Exercise Price			Aggregate Intrinsic Value (000's)			Weighted Average Remaining Contractual Term (in years)
Balance, December 31, 2012	71,001			$	19.73		$	42,647	1.3
Assumed in acquisitions	540,179			$	260.96
Exercised	(449,670	)		$	194.68
Forfeited	(23,802	)		$	478.83
Balance, December 31, 2013	137,708			$	315.36		$	116,686	6.6
Assumed in acquisitions	61,897			$	457.67
Exercised	(51,003	)		$	293.59
Forfeited	(2,217	)		$	517.91
Balance, December 31, 2014	146,385			$	380.05		$	111,277	6.5
Assumed in acquisitions	1,422			$	230.37
Exercised	(52,697	)		$	355.85
Forfeited	(6,006	)		$	511.87
Balance, December 31, 2015	89,104			$	383.03		$	79,474	5.4
Vested and exercisable as of December 31, 2015	72,654			$	354.59		$	66,868	5.0
Vested and exercisable as of December 31, 2015 and expected to vest thereafter, net of estimated forfeitures	88,687			$	383.06		$	79,099	5.4

The aggregate intrinsic value of employee stock options exercised during the years ended December 31, 2015, 2014 and 2013 was $46.3 million, $49.2 million and $281.8 million, respectively. During the years ended December 31, 2015, 2014 and 2013, stock options assumed in acquisitions vested for 38,689, 41,524 and 65,293 shares with an acquisition-date fair value of $24.4 million, $24.2 million and $30.9 million, respectively.

For the years ended December 31, 2015, 2014 and 2013, the Company recorded stock-based compensation expense related to employee stock options of $24.9 million, $24.7 million and $30.9 million, respectively. Employee stock options assumed in acquisitions during the year ended December 31, 2015 had a total acquisition-date fair value of $1.4 million based on a weighted-average acquisition date fair value of $1,015.81 per share. As of December 31, 2015, there was $9.7 million of total future compensation costs related to unvested employee stock options to be recognized over a weighted-average period of 1.3 years.