(6)Equity-Based Compensation

Our general and administrative expenses include equity-based compensation costs allocated to us by Antero Resources for grants made pursuant to Antero Resources’ long‑term incentive plan and the Midstream LTIP. Equity‑based compensation expense allocated to us was $6.0 million and $6.3 million for the three months ended March 31, 2016 and 2017, respectively. These expenses were allocated to us based on our proportionate share of Antero Resources’ labor costs. Antero Resources has unamortized expense totaling approximately $157.1 million as of March 31, 2017 related to its various equity-based compensation plans, which includes 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 Resources employs the personnel who provide support to our operations pursuant to a secondment agreement between us and Antero Resources. AMGP has 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 7,944,445 common units are available for future grant under the Midstream LTIP as of March 31, 2017. 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 and distribution equivalent rights are delivered to the holder of the phantom units. Compensation related to each 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 Resources. Antero Resources recognizes compensation expense for the units awarded and a portion of that expense is allocated to the Partnership. Antero Resources allocates equity-based compensation expense to the Partnership based on our proportionate share of Antero Resources’ 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 phantom unit awards activity during the three months ended March 31, 2017 is as follows:


		Weighted average		Aggregate
	Number of units	grant date fair value		intrinsic value (in thousands)
Total awarded and unvested—December 31, 2016	1,331,961	$	27.31	$	41,131
Granted	5,967	$	33.52
Vested	—	$	—
Forfeited	(16,327)	$	29.00
Total awarded and unvested—March 31, 2017	1,321,601	$	27.33	$	43,824

Intrinsic values are based on the closing price of the Partnership’s common units on the referenced dates. Midstream LTIP unamortized expense of $29.0 million at March 31, 2017, is expected to be recognized over a weighted average period of approximately 1.9 years and our proportionate share will be allocated to us as it is recognized.