Tallgrass

MarkWest Energy Partners is engaged in the gathering, transmission and processing of natural gas and the transportation, fractionation and storage of natural gas liquids. The company processes gas from the Appalachian Basin and Michigan. Through several acquisitions completed during 2003 and 2004, the company has also expanded the geographic coverage of its natural gas gathering, processing and transmission to the southwest United States. In addition, one of its acquisitions in Michigan has allowed the company to enter into the crude oil transportation business. MarkWest Energy Partners is a publicly owned company. Its shares are listed on the American Stock Exchange under the ticker symbol MWE. The company is headquartered in Englewood, Colo.

Colorado Energy Minerals Inc. is a private, family and employee-owned oil and gas exploration company based in Denver, Colorado, boasting over 110 years of combined experience in the industry. The company specializes in mineral acquisitions, oil and gas production, and property management, highlighting its expertise with a Certified Minerals Manager and Registered Professional Engineers on staff. With over 20 years of experience in acquiring both producing and non-producing minerals, Colorado Energy Minerals actively engages in oil and gas leasing and sales across multiple Rocky Mountain basins. The firm is dedicated to conducting economic evaluations and reserve estimates, ensuring comprehensive management of both in-house and third-party oil and gas properties. Generated from the website

Suncor Energy (U.S.A.) is a part of Suncor Energy, which is an integrated energy company. Suncor Energy specializes in natural gas production. The company conducts pipeline and refining operations in Colorado and Wyoming. It offers gasoline and diesel fuel under the Phillips 66 brand. The company has been in operation since 1967. Suncor Energy employs a staff of more than 6,500 individuals. It also maintains an ethanol production facility in Ontario. The company provides crude oil, as well as online information on biofuel. In addition, it operates wind farms and oil refineries. Suncor Energy is one of the leading energy producers and marketers in North America.