KBR is a company providing professional services, project delivery, and technologies.
Phillips 66 is an energy manufacturing and logistics company with midstream, chemicals, refining and marketing, and specialties businesses.
Halliburton Energy Services is a provider of products and services to the energy industry.
Occidental Petroleum Corporation is an oil and gas exploration and production company.
Enterprise Products Partners is a company providing midstream energy services.
LyondellBasell is a company operating as a manufacturer of chemicals and polymers.
Select Energy Services is a company providing water-management solutions to the oil and gas industry.
Westlake Chemical Corporation is an international manufacturer and supplier of petrochemicals, plastics, and fabricated products.
Kraton Performance Polymers is a global producer of engineered polymers used to enhance the performance of products that touch virtually every aspect of human life.
NL Industries (formerly known as the National Lead Company) is a lead smelting company.
Adams Resources and Energy, Inc. is a company engaged in the production and marketing of crude oil, natural gas, and liquid chemical products.
Gekko is a company which specializes in the procurement and supply of equipment for the oil industry, petrochemical, refineries, OEM's, power generation and marine markets.