Robert J. Proffit

Grey Wolf, Inc. provides contract oil and gas land drilling services. The company was founded in 1980 and is headquartered in Houston, TX.

GulfTerra Energy Partners is the gatherer of oil and gas in the offshore Gulf of Mexico, specializing in the development of pipeline and platform infrastructure for the Deepwater Trend. Enterprise Products Partners LP acquired the company and its name was changed to Enterprise GTM Holdings LP.

PVR Partners LP engaged in the gathering and processing of natural gas and the management of coal and natural resource properties in the United States. It operates through three business segments: Eastern Midstream, Midcontinent Midstream and Coal & Natural Resource Management. The Eastern Midstream segment is engaged in providing natural gas gathering, and other related services in Pennsylvania and West Virginia. The Midcontinent Midstream segment is engaged in providing natural gas processing, gathering services, and other related services. These processing and gathering systems are located primarily in Oklahoma and Texas. The Coal & Natural Resource Management segment involves in the management and leasing of coal properties and the subsequent collection of royalties. It also involves in other land management activities, such as selling standing timber, leasing coal-related infrastructure facilities and collecting oil and gas royalties. The company was founded in July 2001 and is headquartered in Radnor, PA.