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Exhibit 21.1
| NAME | JURISDICTION OF FORMATION | |
|---|---|---|
| MarkWest Energy Operating Company, L.L.C. | Delaware | |
| West Shore Processing Company, L.L.C. | Michigan | |
| Basin Pipeline, L.L.C. | Michigan | |
| MarkWest Energy Appalachia, L.L.C. | Delaware | |
| MarkWest Texas GP, L.L.C. | Delaware | |
| MW Texas Limited, L.L.C. | Delaware | |
| MarkWest Michigan Pipeline Company, L.L.C. | Michigan | |
| MarkWest Western Oklahoma Gas Company, L.L.C. | Oklahoma | |
| MarkWest Power Tex L.P. | Texas | |
| MarkWest Pinnacle, L.P. | Texas | |
| MarkWest PNG Utility, L.P. | Texas | |
| MarkWest Texas PNG Utility, L.P. | Texas | |
| MarkWest Blackhawk, L.P. | Texas | |
| MarkWest Energy East Texas Gas Company, L.P. | Delaware | |
| MarkWest Pipeline Company, L.P. | Texas | |
| MarkWest New Mexico, L.P. | Texas | |
| MarkWest Javelina Company | Texas | |
| MarkWest Javelina Holding Company, L.P. | Delaware | |
| MarkWest Javelina Pipeline Company | Texas | |
| MarkWest Javelina Pipeline Holding, L.P. | Oklahoma | |
| Bright Star Partnership | Texas |
LIST OF SUBSIDIARIES