| Company | Symbol | % Assets |
|---|
| Enterprise Products Partners L. | EPD | 9.62 |
| Kinder Morgan Energy Partners, | KMP | 9.21 |
| Plains All American Pipeline, L | PAA | 7.46 |
| Magellan Midstream Partners L.P | MMP | 7.26 |
| Energy Transfer Partners, L.P. | ETP | 6.82 |
| ONEOK Partners, L.P. Common Sto | OKS | 5.58 |
| MarkWest Energy Partners, LP Co | MWE | 4.84 |
| El Paso Pipeline Partners LP Co | EPB | 4.38 |
| Buckeye Partners L.P. Common St | BPL | 4.27 |
| Williams Partners L.P. Common U | WPZ | 4.24 |