Stock Based Compensation

The Compensation Committee of Piedmont's Board of Directors has periodically granted deferred stock awards to all of Piedmont's employees and independent directors. The awards typically vest ratably over a multi-year period, or one year for independent director awards. Certain employees' long-term equity incentive program is split equally between the time-vested awards described above and a multi-year performance share program whereby awards may be earned based upon Piedmont's total stockholder return ("TSR") relative to a peer group's TSR. The peer group is predetermined by the Board of Directors. Any shares earned are awarded at the end of the multi-year performance period and vest upon award.

A rollforward of Piedmont's equity based award activity for the six months ended June 30, 2017 is as follows:



	Shares		Weighted-Average Grant Date Fair Value
Unvested Stock Awards as of December 31, 2016	944,223		$	19.44
Deferred Stock Awards Granted	299,251		$	21.38
Increase in Estimated Potential Future Performance Share Awards, net of forfeitures	150,537		$	28.37
Performance Stock Awards Vested	(118,446	)	$	22.00
Deferred Stock Awards Vested	(301,921	)	$	19.35
Deferred Stock Awards Forfeited	(4,761	)	$	19.57
Unvested Stock Awards as of June 30, 2017	968,883		$	21.94

The following table provides additional information regarding stock award activity during the three and six months ended June 30, 2017 and 2016, respectively (in thousands, except per share amounts):



	Three Months Ended				Six Months Ended
	June 30, 2017		June 30, 2016		June 30, 2017		June 30, 2016
Weighted-Average Grant Date Fair Value of Deferred Stock Granted During the Period	$	21.38	$	19.96	$	21.38	$	19.96
Total Grant Date Fair Value of Deferred Stock Vested During the Period	$	5,551	$	4,319	$	5,841	$	4,659
Share-based Liability Awards Paid During the Period⁽¹⁾	$	—	$	—	$	2,877	$	1,127


⁽¹⁾	Amounts reflect the issuance of performance share awards related to the 2014-16 and 2013-15 Performance Share Plans during the six months ended June 30, 2017 and 2016, respectively.

A detail of Piedmont’s outstanding stock awards as of June 30, 2017 is as follows:



Date of grant	Type of Award	Net Shares Granted ⁽¹⁾	Grant Date Fair Value		Vesting Schedule	Unvested Shares as of June 30, 2017
January 3, 2014	Deferred Stock Award	86,769	$	16.56	Of the shares granted, 20% vested or will vest on January 3, 2015, 2016, 2017, 2018, and 2019, respectively.	35,094
May 1, 2015	Deferred Stock Award	216,919	$	17.59	Of the shares granted, 25% vested on the date of grant, and 25% vested or will vest on May 1, 2016, 2017, and 2018, respectively.	67,747
May 1, 2015	Fiscal Year 2015-2017 Performance Share Program	—	$	18.42	Shares awarded, if any, will vest immediately upon determination of award in 2018.	229,828	⁽²⁾
May 24, 2016	Deferred Stock Award	233,073	$	19.91	Of the shares granted, 25% vested on the date of grant, and 25% vested or will vest on May 24, 2017, 2018, and 2019, respectively.	134,117
May 24, 2016	Fiscal Year 2016-2018 Performance Share Program	—	$	23.02	Shares awarded, if any, will vest immediately upon determination of award in 2019.	85,792	⁽²⁾
May 18, 2017	Deferred Stock Award-Board of Directors	26,187	$	21.38	Of the shares granted, 100% will vest by May 18, 2018.	26,187
May 18, 2017	Deferred Stock Award	246,808	$	21.38	Of the shares granted, 25% vested on the date of grant, and 25% vested or will vest on May 18, 2018, 2019, and 2020, respectively.	202,233
May 18, 2017	Fiscal Year 2017-2019 Performance Share Program	—	$	30.45	Shares awarded, if any, will vest immediately upon determination of award in 2020.	187,885	⁽²⁾
Total						968,883


⁽¹⁾	Amounts reflect the total grant to employees and independent directors, net of shares surrendered upon vesting to satisfy required minimum tax withholding obligations through June 30, 2017.


⁽²⁾	Estimated based on Piedmont's cumulative TSR for the respective performance period through June 30, 2017. Share estimates are subject to change in future periods based on both Piedmont's and its peers' stock performance and dividends paid.

During the three months ended June 30, 2017 and 2016, Piedmont recognized approximately $2.6 million and $3.2 million of compensation expense related to stock awards, of which $1.1 million and $1.7 million related to the amortization of unvested shares, respectively. During the six months ended June 30, 2017 and 2016, Piedmont recognized approximately $5.7 million and $5.7 million of compensation expense related to stock awards, of which $3.9 million and $4.2 million related to the amortization of unvested shares, respectively. During the six months ended June 30, 2017, a net total of 254,532 shares were issued to employees and independent directors. As of June 30, 2017, approximately $6.4 million of unrecognized compensation cost related to unvested deferred stock awards remained, which Piedmont will record in its consolidated statements of income over a weighted-average vesting period of approximately two years.