(5)Equity-Based Compensation

Our general and administrative expenses include equity-based compensation costs allocated to us by Antero for grants made pursuant to: (i) the Antero Resources Corporation Long‑Term Incentive Plan (the “Antero LTIP”); (ii) profits interests awards valued in connection with the Antero reorganization pursuant to its initial public offering of common stock, which closed on October 16, 2013; and (iii) the Midstream LTIP. Equity‑based compensation expense allocated to us was $2.1 million and $5.3 million for the three months ended September 30, 2014 and 2015, respectively, and $7.4 million and $17.7 million for the nine months ended September 30, 2014 and 2015, respectively. These expenses were allocated to us based on our proportionate share of Antero’s labor costs. Antero has unamortized expense totaling approximately $175 million as of September 30, 2015 related to its various equity-based compensation plans and the Midstream LTIP. A portion of this will be allocated to us as it is amortized over the remaining service period of the related awards.

Midstream LTIP

Our general partner manages our operations and activities and Antero employs the personnel who provide support to our operations. In connection with the IPO, our general partner adopted the Midstream LTIP, pursuant to which non‑employee directors of our general partner and certain officers, employees and consultants of our general partner and its affiliates are eligible to receive awards representing ownership interests in the Partnership. An aggregate of 10,000,000 common units may be delivered pursuant to awards under the Midstream LTIP, subject to customary adjustments. A total of 7,658,363 common units are available for future grant under the Midstream LTIP as of September 30, 2015. Restricted units and phantom units granted under the Midstream LTIP vest subject to the satisfaction of service requirements, upon the completion of which common units in the Partnership are delivered to the holder of the restricted units or phantom units. Compensation related to each restricted unit and phantom unit award is recognized on a straight-line basis over the requisite service period of the entire award. The grant date fair values of these awards are determined based on the closing price of the Partnership’s common units on the date of grant. These units are accounted for as if they are distributed by the Partnership to Antero. Antero recognizes compensation expense for the units awarded and a portion of that expense is allocated to the Partnership. Antero allocates equity-based compensation expense to the Partnership based on our proportionate share of Antero’s direct labor costs. The Partnership’s portion of the equity-based compensation expense is included in general and administrative expenses, and recorded as a credit to the applicable classes of partners’ capital.

A summary of restricted unit and phantom unit awards activity during the nine months ended September 30, 2015 is as follows:


		Weighted average		Aggregate
	Number of units	grant date fair value		intrinsic value (in thousands)
Total awarded and unvested, December 31, 2014	2,381,440	$	29.00	$	65,490
Granted	12,057	$	24.88	$	—
Vested	—	$	—	$	—
Forfeited	(51,860)	$	29.00	$	—
Total awarded and unvested, September 30, 2015	2,341,637	$	28.98	$	41,822

Intrinsic values are based on the closing price of the Partnership’s common units on the referenced dates. Unamortized expense of $52.5 million at September 30, 2015 is expected to be recognized by Antero over a weighted average period of approximately 3.1 years. A proportionate share of the expense will be allocated to us as it is recognized by Antero.