Michael Jennings

Frontier Oil Corp. is an energy company, which is engaged in crude oil refining and wholesale marketing of refined petroleum products. The company operates refineries in Cheyenne, Wyoming and El Dorado, Kansas. Frontier Oil purchases crude oil to be refined and markets the refined petroleum products produced, including various grades of gasoline, diesel fuel, jet fuel, asphalt, chemicals and petroleum coke. The Cheyenne Refinery has a permitted crude oil capacity of 52,000 bpd and markets its refined products primarily in the Eastern slope of the Rocky Mountain region, which encompasses Eastern Colorado, Eastern Wyoming and Western Nebraska. It has a coking unit, which allows the refinery to process heavy crude oil for use as a feedstock. The El Dorado Refinery is in the Plains States and the Rocky Mountain region with crude oil capacity of 135,000 bpd. It markets gasoline and diesel in Denver and throughout the Plains States. Frontier Oil also owns Ethanol Management Co., a products terminal and blending facility located near Denver, Colorado. The company was founded in 1949 and is headquartered in Houston, TX.

Unimin Corp. provides industrial mineral mining and production services. It offers silica, quartz, feldspar, nepheline syenite, calcium carbonate, clay, kaolin, lime and limestone products. The company was founded in 1970 and is headquartered in New Canaan, CT.

Cameron International Corp. designs, manufactures, markets and services equipment used by the oil and gas industry and industrial manufacturing companies. It provides flow equipment products, systems and services to worldwide oil, gas and process industries. The company was founded by Harry Cameron and James Abercrombie in 1920 and is headquartered in Houston, TX.

ION Geophysical Corp. engages in the provision of geoscience technology, services, and solutions to the oil and gas industry. It operates through the E&P Technology and Services, and Operations Optimization segments. The E&P Technology and Services segment creates digital data assets and delivers services that improve decision-making, mitigate risk and maximize portfolio value for E&P companies. The Operations Optimization segment develops mission-critical subscription offerings and engineering services that enable operational control and optimization offshore. The company was founded in 1968 and is headquartered in Houston, TX.

HollyFrontier Corp. is an independent petroleum refiner and marketer. It specializes in gasoline, diesel fuel, jet fuel, and modified asphalt. The firm operates through the following segments: Refining, Lubricants and Specialty Products, and Holly Energy Partners LP (HEP). The Refining segment includes the operations in its El Dorado, Tulsa, Navajo, Cheyenne, and Woods Cross Refineries. The Lubricants and Specialty Products segment offers base oil production activities, by-product sales to third parties, and intra-segment base oil sales, which includes the purchase of base oils and the blending, packaging, marketing and distribution, and sales of finished lubricants and specialty products to third parties. The HEP segment relates to all of the operations of HEP. The company was founded in 1947 and is headquartered in Dallas, TX.

Part of HF Sinclair Corp, Holly Logistic Services LLC is a private company that provides logistics services. The company is based in Dallas, TX. Michael C. Jennings has been the CEO of the company since 2011.

Holly Energy Partners LP engages in the business of operating a system of petroleum product and crude pipelines, storage tanks, distribution terminals, and loading rack facilities. It operates through the Pipelines and Terminals, and Refinery Processing Unit segments. The Pipelines and Terminals segment includes petroleum products, crude pipelines and terminal, tankage, and loading rack facilities. The company was founded in 2004 and is headquartered in Dallas, TX.