Attached files

file filename
10-K - 10-K - MARKWEST ENERGY PARTNERS L Pa2196773z10-k.htm
EX-23.1 - EX-23.1 - MARKWEST ENERGY PARTNERS L Pa2196773zex-23_1.htm
EX-31.2 - EX-31.2 - MARKWEST ENERGY PARTNERS L Pa2196773zex-31_2.htm
EX-31.1 - EX-31.1 - MARKWEST ENERGY PARTNERS L Pa2196773zex-31_1.htm
EX-12.1 - EX-12.1 - MARKWEST ENERGY PARTNERS L Pa2196773zex-12_1.htm
EX-32.1 - EX-32.1 - MARKWEST ENERGY PARTNERS L Pa2196773zex-32_1.htm
EX-32.2 - EX-32.2 - MARKWEST ENERGY PARTNERS L Pa2196773zex-32_2.htm
EX-10.40 - EX-10.40 - MARKWEST ENERGY PARTNERS L Pa2196773zex-10_40.htm
EX-10.41 - EX-10.41 - MARKWEST ENERGY PARTNERS L Pa2196773zex-10_41.htm
EX-10.39 - EX-10.39 - MARKWEST ENERGY PARTNERS L Pa2196773zex-10_39.htm

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Exhibit 21.1

Entity
  State of Incorporation

Bright Star Partnership

  Texas

Centrahoma Processing LLC

  Delaware

MarkWest Blackhawk, L.L.C. 

  Texas

MarkWest Energy Appalachia, L.L.C. 

  Delaware

MarkWest Energy East Texas Gas Company, L.L.C. 

  Delaware

MarkWest Energy Finance Corporation

  Delaware

MarkWest Energy GP, L.L.C. 

  Delaware

MarkWest Energy Operating Company, L.L.C. 

  Delaware

MarkWest Gas Marketing, L.L.C. 

  Texas

MarkWest Gas Services, L.L.C. 

  Texas

MarkWest Hydrocarbon, Inc. 

  Delaware

MarkWest Javelina Company, L.L.C. 

  Texas

MarkWest Javelina Pipeline Company, L.L.C. 

  Texas

MarkWest Liberty Gas Gathering, L.L.C. 

  Delaware

MarkWest Liberty Midstream & Resources, L.L.C. 

  Delaware

MarkWest Marketing, L.L.C. 

  Delaware

MarkWest McAlester, L.L.C. 

  Oklahoma

MarkWest Michigan Pipeline Company, L.L.C. 

  Michigan

MarkWest New Mexico, L.L.C. 

  Texas

MarkWest Oklahoma Gas Company, L.L.C. 

  Oklahoma

MarkWest Pinnacle, L.L.C. 

  Texas

MarkWest Pioneer, L.L.C. 

  Delaware

MarkWest Pipeline Company, L.L.C. 

  Texas

MarkWest PNG Utility, L.L.C. 

  Texas

MarkWest Power Tex, L.L.C. 

  Texas

MarkWest Texas PNG Utility, L.L.C. 

  Texas

Mason Pipeline Limited Liability Company

  Michigan

Matrex, L.L.C. 

  Michigan

West Shore Processing Company, L.L.C. 

  Michigan

Wirth Gathering, a general partnership

  Oklahoma



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