| Name | Country | Market Cap (US$) |
|---|
| A&L Underground, Inc. | United States | Private |
| Alberta Natural Gas Company Ltd | Canada | Private |
| Algonquin Gas Transmission Company | United States | Private |
| Alyeska Pipeline Service Company | United States | Private |
| ANR Pipeline Company | United States | Private |
| ARCO Pipe Line Company | United States | Private |
| B P Pipelines (North America) Inc. | United States | Private |
| Bandt plc | United Kingdom | Private |
| Belle Fourche Pipeline Company | United States | Private |
| Boardwalk Pipelines, LP | United States | Private |
| British Pipeline Agency Ltd | United Kingdom | Private |
| Buckeye Pipe Line Company, L P | United States | Private |
| Centragas Transportadora De Gas De La Region Central | Colombia | Private |
| Citrus Corporation | United States | Private |
| CLFX Corporation | United States | Private |
| Coastal Empire State Inc. | United States | Private |
| Colonial Pipeline Company | United States | Private |
| Colorado Interstate Gas Co. | United States | Private |
| Columbia Gas Transmission Corporation | United States | Private |
| Columbia Gulf Transmission Company | United States | Private |
| Conoco Pipe Line Company | United States | Private |
| Dominion Transmission Inc | United States | Private |
| Enbridge (U.S.) Inc. | United States | Private |
| Explorer Pipeline Company | United States | Private |
| ExxonMobil Pipeline Company | United States | Private |
| Florida Gas Transmission Company, LLC | United States | Private |
| Genesis Crude Oil, L.P. | United States | Private |
| Great Lakes Gas Transmission Company | United States | Private |
| Gulfmark Energy, Inc. | United States | Private |
| Hanover Energy Inc. | United States | Private |
| Interpipe Scientific Production Investment Group Jsc | Ukraine | Private |
| Iroquois Gas Transmission System L.P. | United States | Private |
| Jayhawk Pipeline, LLC | United States | Private |
| Kentucky West Virginia Gas Co. | United States | Private |
| Koch Gateway Pipe Line Company | United States | Private |
| LG&E Energy Marketing Inc. | United States | Private |
| Litoral Gas S.A. | Argentina | Private |
| Loop Inc. | United States | Private |
| Lorenz Industries, Inc | United States | Private |
| Marathon Pipe Line Company | United States | Private |
| Market Hub Partners Storage LP | United States | Private |
| Michigan Gas Storage Company | United States | Private |
| Montreal Pipe Line Limited | Canada | Private |
| Nashville Gas Company | United States | Private |
| National Fuel Gas Supply Corporation | United States | Private |
| Natural Gas Pipeline Co. of America | United States | Private |
| Noordgastransport B.V. | Netherlands | Private |
| Northern Border Pipeline Company | United States | Private |
| NOVA Gas Transmission Ltd. | Canada | Private |
| NuStar Logistics L.P. | United States | Private |
| NuStar Pipeline Operating Partnership LP | United States | Private |
| OJSC AK Transnefteproduct | Russia | Private |
| Oklahoma Natural Gas Company | United States | Private |
| Oleoducto de Colombia S.A. | Colombia | Private |
| Olympic Pipe Line Company | United States | Private |
| Oman Water Pumps Mfg. Co SAOG | Oman | Private |
| PG&E Gas Transmission-Northwest | United States | Private |
| Plantation Pipe Line Company | United States | Private |
| Przedsiebiorstwo Eksploatacji Rurociagow Naftowych Przyjazn S A | Poland | Private |
| Questar Pipeline Company | United States | Private |
| Santa Fe Pacific Pipeline Partners | United States | Private |
| Shell Pipeline Company L P | United States | Private |
| Stanton plc | United Kingdom | Private |
| Ste Du Pipeline Mediterranee- Rhone | France | Private |
| Sunoco Logistics Partners Operations LP | United States | Private |
| Teppco Crude Pipeline Lp | United States | Private |
| TEPPCO Partners, L.P. | United States | Private |
| Terasen Pipelines (Trans Mountain) Inc. | Canada | Private |
| Texas Brine Company Llc | United States | Private |
| Texas Eastern Corporation | United States | Private |
| Texas Eastern Transmission LP | United States | Private |
| Texas Gas Transmission LLC | United States | Private |
| Thai Petroleum Pipeline Co Ltd | Thailand | Private |
| TotalFinaElf Exploration UK plc | United Kingdom | Private |
| Trans Mountain Pipe Line Co., Ltd. | Canada | Private |
| Transok Inc. | United States | Private |
| Transpetrol, A.S. | Slovakia | Private |
| Transportadora de Gas del Interior S.A. E.S.P. | Colombia | Private |
| Truckee Meadows Water Authority | United States | Private |
| Trunkline Gas Company | United States | Private |
| WBI Holdings, Inc. | United States | Private |
| Westcoast Gas Services Inc. | Canada | Private |
| Williams Natural Gas Company | United States | Private |
| Williams Pipe Line Co. | United States | Private |
| Wolverine Pipe Line Company | United States | Private |
|