Marathon Petroleum Corp., owner of the Speedway chain, closed on the acquisition of Andeavor (formerly Tesoro) in 2018. The $23.3 billion deal included a portfolio of 1,085 stations under brands including SuperAmerica, Giant, Mustang, Sundial and Howdy's.

San Antonio-based Andeavor's refineries in California, the midcontinent and the Pacific Northwest complemented Findlay, Ohio-based Marathon Petroleum’s Gulf Coast and Midwest refining footprint. The combined company became the No. 1 U.S. refiner by capacity, with 16 refineries.

The transaction created a nationwide marketing portfolio, combining Marathon Petroleum's strength east of the Mississippi with Andeavor’s strong presence in the western United States. Marathon’s marketing portfolio included nearly 4,000 Speedway company-owned c-stores and 7,800 Marathon-branded dealer locations.

"This transformative transaction is a significant milestone in our company's more than 130-year history," said Marathon Petroleum’s Heminger. "MPC is now the leading refining, midstream and marketing company in the U.S. and is well-positioned for long-term growth and shareholder value creation."
*Includes refinery