Enterprise Products Partners L.P. provides midstream energy services to producers and consumers of natural gas, natural gas liquids (NGLs), crude oil, petrochemicals, and refined products. It operates in four segments: NGL Pipelines & Services, Crude Oil Pipelines & Services, Natural Gas Pipelines & Services, and Petrochemical & Refined Products Services. The NGL Pipelines & Services segment offers natural gas processing and related NGL marketing services. It operates natural gas processing facilities located in Colorado, Louisiana, Mississippi, New Mexico, Texas, and Wyoming; NGL pipelines; NGL fractionation facilities; NGL and related product storage facilities; and NGL marine terminals. The Crude Oil Pipelines & Services segment operates crude oil pipelines; and crude oil storage and marine terminals, which include a fleet of approximately 250 tractor-trailer tank trucks that are used to transport crude oil. It also engages in crude oil marketing activities. The Natural Gas Pipelines & Services segment operates natural gas pipeline systems to gather, treat, and transport natural gas. It leases underground salt dome natural gas storage facilities in Napoleonville, Louisiana; owns an underground salt dome storage cavern in Wharton County, Texas; and markets natural gas. The Petrochemical & Refined Products Services segment operates propylene fractionation facilities, including propylene fractionation units and propane dehydrogenation facilities, and related marketing activities; butane isomerization complex and related deisobutanizer operations; and octane enhancement, isobutane dehydrogenation, and high purity isobutylene production facilities. It also operates refined products pipelines and terminals; and ethylene export terminals; and provides refined products marketing and marine transportation services. Enterprise Products Partners L.P. was founded in 1968 and is headquartered in Houston, Texas.

Hess Corporation, an exploration and production company, explores, develops, produces, purchases, transports, and sells crude oil, natural gas liquids (NGLs), and natural gas. The company operates in two segments, Exploration and Production, and Midstream. It conducts production operations primarily in the United States, Guyana, the Malaysia/Thailand Joint Development Area, and Malaysia; and exploration activities principally offshore Guyana, the U.S. Gulf of Mexico, and offshore Suriname and Canada. The company is also involved in gathering, compressing, and processing natural gas; fractionating NGLs; gathering, terminaling, loading, and transporting crude oil and NGL through rail car; and storing and terminaling propane, as well as providing water handling services primarily in the Bakken Shale plays in the Williston Basin area of North Dakota. The company was incorporated in 1920 and is headquartered in New York, New York.

Targa Resources Corp., together with its subsidiary, Targa Resources Partners LP, owns, operates, acquires, and develops a portfolio of complementary domestic midstream infrastructure assets in North America. It operates in two segments, Gathering and Processing, and Logistics and Transportation. The company is involved in gathering, compressing, treating, processing, transporting, and selling natural gas; storing, fractionating, treating, transporting, and selling natural gas liquids (NGL) and NGL products, including services to liquefied petroleum gas exporters; and gathering, storing, terminaling, purchasing, and selling crude oil. It is also involved in the purchase and resale of NGL products; and sale of propane, as well as provision of related logistics services to multi-state retailers, independent retailers, and other end-users. In addition, the company offers NGL balancing services; and transportation services to refineries and petrochemical companies in the Gulf Coast area, as well as purchases, markets, and resells natural gas. As of December 31, 2023, it leased and managed approximately 605 railcars; 137 tractors; and 6 vacuum trucks and 2 pressurized NGL barges. Targa Resources Corp. was incorporated in 2005 and is headquartered in Houston, Texas.

Plains All American Pipeline, L.P., through its subsidiaries, engages in the pipeline transportation, terminaling, storage, and gathering of crude oil and natural gas liquids (NGL) in the United States and Canada. The company operates through two segments, Crude Oil and NGL. The Crude Oil segment offers gathering and transporting crude oil through pipelines, gathering systems, trucks, and on barges or railcars. This segment provides terminaling, storage, and other facilities-related services, as well as merchant activities. The NGL segment is involved in natural gas processing and NGL fractionation, storage, transportation, and terminaling. This segment also includes ethane, propane, normal butane, iso-butane, and natural gasoline derived from natural gas production and processing activities, as well as crude oil refining processes. Its NGL components are used for various applications, such as heating, engine, and industrial fuels. The company was founded in 1981 and is headquartered in Houston, Texas. Plains All American Pipeline, L.P. operates as a subsidiary of Plains GP Holdings, L.P.

EnLink Midstream, LLC provides midstream energy services in the United States. The company operates through Permian, Louisiana, Oklahoma, North Texas, and Corporate segments. It is involved in gathering, compressing, treating, processing, transporting, storing, and selling natural gas; fractionating, transporting, storing, and selling natural gas liquids; and gathering, transporting, stabilizing, storing, trans-loading, and selling crude oil and condensate, as well as providing brine disposal services. In addition, the company's midstream energy asset network includes natural gas processing plants; fractionators; barge and rail terminals; product storage facilities; and brine disposal wells. EnLink Midstream, LLC was incorporated in 2013 and is based in Dallas, Texas.

Plains GP Holdings, L.P., through its subsidiary, Plains All American Pipeline, L.P., owns and operates midstream infrastructure systems in the United States and Canada. It operates in two segments, Crude Oil and Natural Gas Liquids (NGLs). The company engages in the gathering and transporting crude oil and NGLs using pipelines, gathering systems, and trucks. It engages in the loading and unloading services at terminals; NGL fractionation and isomerization services; and natural gas and condensate processing services. The company offers logistics services to producers, refiners, and other customers. PAA GP Holdings LLC operates as a general partner of the company. Plains GP Holdings, L.P. was incorporated in 2013 and is headquartered in Houston, Texas.

Summit Midstream Corporation focuses on owning, developing, and operating midstream energy infrastructure assets primarily shale formations in the continental United States. It operates natural gas, crude oil, and produced water gathering systems in four unconventional resource basins, including the Williston Basin in North Dakota, which includes the Bakken and Three Forks shale formations; the Denver-Julesburg Basin that consists of the Niobrara and Codell shale formations in Colorado and Wyoming; the Fort Worth Basin in Texas, which comprises the Barnett Shale formation; and the Piceance Basin in Colorado, which includes the Mesaverde formation, as well as the emerging Mancos and Niobrara Shale formations. It serves natural gas and crude oil producers. Summit Midstream Corporation was founded in 2012 and is based in Houston, Texas.

Summit Midstream Partners, LP focuses on owning, developing, and operating midstream energy infrastructure assets primarily shale formations in the continental United States. The company provides natural gas gathering, compression, treating, and processing services, as well as crude oil and produced water gathering and freshwater delivery services. Its assets include Summit Utica system comprising the Utica and Point Pleasant shale formations in southeastern Ohio; Mountaineer Midstream system that includes the Marcellus shale in the Appalachian Basin in West Virginia; Polar and Divide system includes the Bakken and Three Forks shale formations in northwestern North Dakota; Niobrara G&P system, which comprises the Niobrara and Codell shale formations located near Hereford, Colorado. The company's assets also include Double E, a 135 mile interstate natural gas transmission pipeline; Grand River system that gathers natural gas produced from the Mancos and Niobrara shale formations in western Colorado; and DFW Midstream system comprising the Barnett Shale formation located in north-central Texas. In addition, it owns an ownership interest in Ohio Gathering, which owns and operates natural gas gathering and condensate stabilization facility in the Utica Shale in southeastern Ohio. It serves natural gas and crude oil producers. Summit Midstream GP, LLC operates as a general partner of the company. Summit Midstream Partners, LP was founded in 2009 and is based in Houston, Texas.