Mardi de Verges

Keen Energy Services LLC engages in the contract drilling of onshore oil and natural gas wells for exploration and production companies. The company was founded in 1991 and is headquartered in Stillwater, OK.

CITGO Petroleum Corp. engages in refining, transporting, and marketing of transportation fuels, lubricants, and petrochemicals products. It offers retail gasoline, diesel fuel, jet fuel, lubricants, petrochemicals, and other petroleum-based industrial products. The company was founded by Henry L. Doherty in 1910 and is headquartered in Houston, TX.

Arthur Andersen LLP used to provide accounting services. It was also into consulting services for clients that operate businesses throughout the United States and around the world. Arthur Andersen was founded in 1913 and was headquartered in Chicago, IL.

Level 3 Parent LLC engages in the provision of integrated communications services. The firm offers internet protocol and data such as internet, virtual private network (VPN), Ethernet, content delivery network (CDN), media delivery, vyvx broadcast, managed, and cloud and information technology; and transport and fiber including voice, colocation and data center and security services. It distributes its products to enterprise, content, government and wholesale customers. The company was founded by Kevin J. O'Hara in 1941 and is headquartered in Broomfield, CO.

Wiltel Communications Group, Inc. provides customized communications solutions to enterprises, and federal government. The company was founded by Robert D. Williams and is headquartered in Tulsa, OK.