Abraxas Petroleum is an independent energy company primarily engaged in the acquisition, exploration, development and production of oil and gas. The company's oil and gas assets are located in the Permian/Delaware Basin, the Rocky Mountain, and South Texas. The company's properties in the Permian/Delaware Basin region are located in two sub-basins, the Delaware Basin and the Eastern Shelf. The company's properties in the Rocky Mountain region are primarily located in the Williston Basin of North Dakota and Montana. The company's properties in the South Texas region are located along the Edwards trend in DeWitt and Lavaca Counties, TX and the Eagle Ford shale and the Austin Chalk in Atascosa and McMullen Counties, TX.

Antero Resources is an oil and natural gas company engaged in the exploration, development and production of natural gas, natural gas liquids (NGLs), and oil properties. The company focuses on unconventional reservoirs, which can generally be characterized as fractured shale formations. The company's drilling operations are focused in the Marcellus Shale and Utica Shale of the Appalachian Basin. The company's industry segments are: the exploration, development, and production of natural gas, NGLs, and oil; marketing of excess firm transportation capacity; and the gathering and processing of natural gas. All of the company's operations are conducted in the United States.

ConocoPhillips is an exploration and production company engaged in exploring for, producing, transporting and marketing crude oil, bitumen, natural gas, liquefied natural gas and natural gas liquids. The company's segments include: Alaska, which operates in Alaska; Lower 48, which operates in the United States and the Gulf of Mexico; Canada, which operates in Alberta and British Columbia; Europe and North Africa, which consists of operations and exploration activities in Norway, the United Kingdom and Libya; Asia Pacific and Middle East, which operates in China, Indonesia, Malaysia, Australia, Qatar, and Timor-Leste; and Other International, which operates in Colombia, Chile and Argentina.

Continental Resources is an independent crude oil and natural gas company engaged in the exploration, development, and production of crude oil and natural gas mainly in the North, South and East regions of the U.S. The North region consists of properties north of Kansas and west of the Mississippi River and includes North Dakota Bakken, Montana Bakken, and the Red River units. The South region includes all properties south of Nebraska and west of the Mississippi River including various plays in the South Central Oklahoma Oil Province and Sooner Trend Anadarko Canadian Kingfisher areas of Oklahoma. The East region is comprised of undeveloped leasehold acreage east of the Mississippi River.

Delek US Holdings is a holding company. Through its subsidiaries, the company is engaged in the downstream energy business focused on petroleum refining, the transportation, storage and wholesale distribution of crude oil, intermediate and refined products and convenience store retailing. The company's segments are: refining, which processes crude oil and other feedstocks for the manufacture of transportation motor fuels; logistics, which gathers, transports and stores crude oil and markets, distributes, transports and stores refined products; and retail, which includes the operations of Alon USA Energy, Inc.'s convenience store sites located primarily in central and West Texas and New Mexico.

Denbury Resources is an independent oil and natural gas company. The company's operations are focused in two main operating areas: the Gulf Coast and Rocky Mountain regions. The company's properties with proved and producing reserves in the Gulf Coast region are situated in Mississippi, Texas, Louisiana and Alabama, and in the Rocky Mountain region are situated in Montana, North Dakota and Wyoming.

Diamond Offshore Drilling provides contract drilling services to the energy industry around the globe. The company's fleet enables it to provide services in the floater market on a worldwide basis. The company's contracts to provide offshore drilling services vary in their terms and provisions. The principal markets for the company's offshore contract drilling services are: the Gulf of Mexico, including the U.S., and Mexico; South America, principally offshore Brazil, and Trinidad and Tobago; Australia and Southeast Asia, including Malaysia, Indonesia, Myanmar and Vietnam; Europe, principally offshore the U.K., and Norway; East and West Africa; and the Mediterranean.

Dorchester Minerals is engaged in the acquisition, ownership and administration of Royalty Properties and Net Profits Interests (NPIs). The Royalty Properties consist of producing and nonproducing mineral, royalty, overriding royalty, net profits, and leasehold interests located in several counties and parishes in several states. The NPIs represent net profits overriding royalty interests in various properties owned by the operating partnership. The company's general partner is Dorchester Minerals Management LP, which is managed by its general partner, Dorchester Minerals Management GP LLC.

Energen is an oil and natural gas exploration and production company engaged in the exploration, development and production of oil, natural gas liquids and natural gas. The company's operations are conducted through its subsidiary, Energen Resources Corporation and primarily occur within the Midland Basin, the Delaware Basin and the Central Basin Platform areas of the Permian Basin in west Texas and New Mexico. The company's operations focus on increasing production and adding proved reserves through the development of oil, natural gas liquids and natural gas properties. In addition, the company explores for and develops new reservoirs, primarily in areas in which it has an operating presence.

Helmerich & Payne provides drilling services and technologies for oil and gas exploration and production companies. The company's contract drilling business segments are: United States Land, which operates in Colorado, Louisiana, Ohio, Oklahoma, Montana, New Mexico, North Dakota, Pennsylvania, Texas, Utah, West Virginia and Wyoming; Offshore, which operates in United States federal waters in the Gulf of Mexico; and International Land, which has rigs in Argentina, Bahrain, Colombia and United Arab Emirates. The company's drilling technology-based business segment, Helmerich & Payne Technologies, is focused on developing, promoting and commercializing technologies designed to improve the drilling operations.

Hess is a global exploration and production company engaged in exploration, development, production, transportation, purchase and sale of crude oil, natural gas liquid (NGL), and natural gas with production operations located primarily in the United States, Guyana, the Malaysia/Thailand Joint Development Area, Malaysia and Denmark. The company's Midstream operating segment provides fee-based services, including gathering, compressing and processing natural gas and fractionating NGL; gathering, terminaling, loading and transporting crude oil and NGL; storing and terminaling propane, and water handling services primarily in the Bakken shale play in the Williston Basin area of North Dakota.

HollyFrontier is a petroleum refiner that produces products such as gasoline, diesel fuel, jet fuel, other lubricant products, and specialty and modified asphalt. The company's segments are: Refining, which involves the purchase and refining of crude oil and wholesale and marketing of refined products; Lubricants and Specialty Products, which includes the production of lubricant products such as base oils, white oils, other products and finished lubricants; and the company's subsidiary, Holly Energy Partners, L.P., which owns and operates logistics and refinery assets consisting of petroleum product and crude oil pipelines, terminals, tankage, loading rack facilities and processing units.

Legacy Reserves is engaged in the acquisition and development of oil and natural gas properties. The company owns and operates oil and natural gas producing properties located primarily in East Texas, the Permian Basin (West Texas and Southeast New Mexico), Rocky Mountain and Mid-Continent regions of the United States. The company is focused on two activities: the acquisition of producing oil and natural gas properties and the development of properties in established producing trends. As of Dec 31 2016, the company had proved reserves of 144.8 million barrels of oil equivalent, consisting of 32.5 million barrels of oil, 7.8 million barrels of natural gas liquids, and 627 billion cubic feet of natural gas.

Marathon Petroleum is an independent petroleum refining and marketing, retail and midstream company. The company's segments include: Refining and Marketing, which refines crude oil and other feedstocks at its refineries, purchases refined products and ethanol for resale and distributes refined products; Retail, which sells transportation fuels and convenience products in the retail market across the U.S.; and Midstream, which transports, stores, distributes and markets crude oil and refined products via refining logistics assets, pipelines, terminals, towboats and barges, gathers, processes and transports natural gas, and gathers, transports, fractionates, stores and markets natural gas liquids.

Phillips 66 is an energy manufacturing and logistics company with midstream, chemicals, refining, and marketing and specialties businesses. The company's segments include: Midstream, which provides crude oil and refined petroleum product transportation, terminaling and processing services, as well as natural gas and natural gas liquids transportation, storage, processing and marketing services; Chemicals, which manufactures and markets petrochemicals and plastics on a worldwide basis; Refining, which refines crude oil and other feedstocks into petroleum products; and Marketing and Specialties, which purchases for resale and markets refined petroleum products, mainly in the United States and Europe.

Pioneer Natural Resources is a holding company. Through its subsidiaries, the company is engaged in oil and gas exploration and production. The company explores for, develops and produces oil, Natural Gas Liquids and gas within the United States, with operations in the Permian Basin in West Texas. The company's portfolio of resources are located in the Spraberry/Wolfcamp oil field.

Plains All American Pipeline is a holding company. Through its subsidiaries, the company owns and operates midstream energy infrastructure and provides logistics services for crude oil, natural gas liquids (NGL) and natural gas. The company has three operating segments: Transportation, which provides activities associated with transporting crude oil and NGL on pipelines, gathering systems, trucks and barges; Facilities, which provides storage, terminalling and throughput services for crude oil, NGL and natural gas, as well as NGL fractionation and isomerization services and natural gas and condensate processing services; and Supply and Logistics, which provides merchant-related activities.

RSP Permian is an independent oil and natural gas company focused on the acquisition, exploration, development and production of unconventional oil and natural gas reserves in the Permian Basin of West Texas. The company designs and manages the well development and supervises operation and maintenance activities on a day-to-day basis. Independent contractors engaged by the company provides all the equipment and personnel associated with these activities. As of Dec 31 2017, the company had total proved reserves of 375.9 million barrels of oil equivalent, consisting of 261.3 million barrels of oil, 295.02 billion cubic feet of natural gas, and 65.4 million barrels of natural gas liquids.

SEACOR Holdings is a holding company with interests in domestic and international transportation and logistics, risk management consultancy and other businesses. The company has four segments: Ocean Transportation and Logistics Services, which owns and operates a fleet of bulk transportation, port and infrastructure, and logistics assets; Inland Transportation and Logistics Services, which provides customer supply chain solutions; Witt O'Brien's, LLC, which provides crisis and emergency management services for both the public and private sectors; and Other, which includes the activity of its subsidiary, CLEANCOR Energy Solutions LLC, and noncontrolling investments in various other businesses.

Skechers USA designs and markets Skechers-branded lifestyle footwear for men, women and children, and performance footwear for men and women under the Skechers Performance brand name. The company also designs and markets men's and women's Skechers branded lifestyle apparel, and license the Skechers brand to others for accessories, leather goods, eyewear and scrub manufacturers, among others. The company's product offering is sold through department and specialty stores, athletic and independent retailers, boutiques and internet retailers. In addition to wholesale distribution, the company's footwear is available at its direct-to-consumer websites and its own retail stores.

Valero Energy is an international manufacturer and marketer of transportation fuels and petrochemical products. The company's segments include: Refining, which includes its refining operations, the associated marketing activities, and logistics assets that support its refining operations; Ethanol, which includes its ethanol operations, the associated marketing activities, and logistics assets that support its ethanol operations; and Renewable Diesel, which includes the operations of its joint ventture, Diamond Green Diesel Holdings LLC, which owns and operates a renewable diesel plant in Norco, LA.

Whiting Petroleum is an independent oil and gas company engaged in development, production, acquisition, and exploration activities primarily in the Rocky Mountains region of the U.S. The company's existing operations and capital programs are focused on organic drilling activities and on the development of previously acquired properties, while selectively pursuing acquisitions that complement its existing properties. The company principally sells its oil and gas production to end users, marketers and other purchasers that have access to nearby pipeline or rail takeaway. In areas with no access to gathering pipelines, oil is trucked or transported to terminals, market hubs, refineries or storage facilities.