Marathon, the parent company of Enon-based Speedway, announced a merger with Andeavor to create the largest U.S. refiner.

Ohio-based Marathon to buy refining company

Marathon announced a merger with Andeavor, a marketing, logistics and refining company based in Texas.

Marathon, based in Findlay, is the parent company of Speedway a convenience store chain headquartered in Enon. Speedway is a major employer in the region and already operates about 2,740 convenience stores in 21 states. Earlier this month, Speedway announced a separate transaction in which the chain purchased about 80 convenience stores held by the Petr-All Petroleum Consulting Corporation in New York state.

Company officials said the merger makes geographic sense for both entities. Andeavor’s operates refineries in California, the Mid-Continent and the Pacific Northwest while Marathon’s footprint largely includes the Gulf Coast and Midwest. The combined company will be the No. 1 U.S. refiner by capacity and a top-five refiner globally, according to a news release from Marathon.

Marathon was the nation’s second-largest refiner, with a crude oil refining capacity of approximately 1.9 million barrels per day before the merger.

“This transaction combines two strong, complementary companies to create a leading U.S. refining, marketing, and midstream company, building a platform that is well-positioned for long-term growth and shareholder value creation,” said Gary R. Heminger, MPC chairman and chief executive officer. “Each of our operating segments are strengthened through this transaction, as it geographically diversifies our refining portfolio into attractive markets, increases access to advantaged feedstocks, enhances our midstream footprint in the Permian basin, and creates a nationwide retail and marketing portfolio that will substantially improve efficiencies and enhance our ability to serve customers.”