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.

MPLX LP owns and operates midstream energy infrastructure and logistics assets primarily in the United States. It operates in two segments, Logistics and Storage, and Gathering and Processing. The company is involved in the gathering, processing, and transportation of natural gas; gathering, transportation, fractionation, storage, and marketing of natural gas liquids; gathering, storage, transportation, and distribution of crude oil and refined products, as well as other hydrocarbon-based products and renewables; and sale of residue gas and condensate. It also engages in the inland marine businesses comprising fleet of boats and barges transportation of light products, heavy oils, crude oil, renewable fuels, chemicals, and feedstocks in the Mid-Continent and Gulf Coast regions, as well as a marine repair facility located on the Ohio River; and distribution of fuel, as well as operates refining logistics, terminals, rail facilities, and storage caverns. In addition, the company operates terminal facilities for the receipt, storage, blending, additization, handling, and redelivery of refined petroleum products through the pipeline, rail, marine, and over-the-road modes of transportation. MPLX GP LLC acts as the general partner of MPLX LP. The company was incorporated in 2012 and is headquartered in Findlay, Ohio. MPLX LP operates as a subsidiary of Marathon Petroleum Corporation.

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.

Western Midstream Partners, LP, together with its subsidiaries, operates as a midstream energy company primarily in the United States. It is involved in gathering, compressing, treating, processing, and transporting natural gas; gathering, stabilizing, and transporting condensate, natural gas liquids (NGLs), and crude oil; and gathering and disposing produced water. The company also buys and sells natural gas, NGLs, and condensate. It operates assets located in Texas, New Mexico, the Rocky Mountains, and North-central Pennsylvania. Western Midstream Holdings, LLC operates as the general partner of the company. The company was formerly known as Western Gas Equity Partners, LP and changed its name to Western Midstream Partners, LP in February 2019. Western Midstream Partners, LP was incorporated in 2007 and is based in The Woodlands, 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.

Hess Midstream LP owns, develops, operates, and acquires midstream assets and provide fee-based services to Hess and third-party customers in the United States. It operates through three segments: Gathering; Processing and Storage; and Terminaling and Export. The Gathering segment owns natural gas gathering and compression systems; crude oil gathering systems; and produced water gathering and disposal facilities. Its gathering systems consists of approximately 1,410 miles of high and low pressure natural gas and natural gas liquids gathering pipelines with capacity of approximately 660 million cubic feet per day; crude oil gathering system comprises approximately 570 miles of crude oil gathering pipelines; and produced water gathering system that includes approximately 300 miles of pipelines in gathering systems. The Processing and Storage segment comprises Tioga Gas Plant, a natural gas processing and fractionation plant located in Tioga, North Dakota; a 50% interest in the Little Missouri 4 gas processing plant located in south of the Missouri River in McKenzie County, North Dakota; and Mentor Storage Terminal, a propane storage cavern and rail, and truck loading and unloading facility located in Mentor, Minnesota. The Terminaling and Export segment owns Ramberg terminal facility; Tioga rail terminal; crude oil rail cars; and other Dakota access pipeline connections, as well as Johnson's Corner Header System, a crude oil pipeline header system. Hess Midstream LP was founded in 2014 and is based in Houston, Texas.

Delek Logistics Partners, LP provides gathering, pipeline, transportation, and other services for crude oil, intermediates, refined products, natural gas, storage, wholesale marketing, terminalling water disposal and recycling customers in the United States. The Gathering and Processing segment consists of pipelines, tanks, and offloading facilities that provide crude oil and natural gas gathering and processing, water disposal and recycling, and storage services, as well as crude oil transportation services to third parties. The Wholesale Marketing and Terminalling segment includes refined products terminals and pipelines in Texas, Tennessee, and Arkansas. This segment provides marketing services for the refined products and terminalling services at refined products terminals to independent third parties. The Storage and Transportation segment comprises tanks, offloading facilities, trucks, and ancillary assets, which provide crude oil, intermediate, and refined products transportation and storage services. Delek Logistics GP, LLC serves as the general partner of the company. Delek Logistics Partners, LP was incorporated in 2012 and is headquartered in Brentwood, Tennessee. Delek Logistics Partners, LP operates as a subsidiary of Delek US Holdings, Inc.

NGL Energy Partners LP engages in the transportation, storage, blending, and marketing of crude oil, natural gas liquids, refined products/renewables, and water solutions. The company operates through three segments: Water Solutions, Crude Oil Logistics, and Liquids Logistics. The Water Solutions segment transports, treats, recycles, and disposes produced and flowback water generated from crude oil and natural gas production; aggregates and sells recovered crude oil; disposes solids, such as tank bottoms, and drilling fluid and muds, as well as performs truck and frac tank washouts; and sells produced water for reuse and recycle, and brackish non-potable water. The Crude Oil Logistics segment purchases crude oil from producers and marketers, and transports it to refineries for resale at pipeline injection stations, storage terminals, barge loading facilities, rail facilities, refineries, and other trade hubs; and provides storage, terminaling, and transportation services through pipelines and storage tanks. The Liquids Logistics segment supplies natural gas liquids, refined petroleum products, and biodiesel to commercial, retail, and industrial customers in the United States and Canada through its 23 terminals, third-party storage and terminal facilities, and nine common carrier pipelines, as well as through a fleet of leased railcars. This segment also provides services for marine exports of butane through its facility located in Chesapeake, Virginia; and owns a propane pipeline in Michigan. NGL Energy Holdings LLC serves as the general partner of the company. The company was founded in 1940 and is headquartered in Tulsa, Oklahoma.