Tesoro Corporation

Tesoro Corporation headquarters, San Antonio

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Anacortes Refinery 31911

Tesoro Corporation was an American petroleum refining, marketing, and logistics company. Founded in 1968 by Dr. Robert V. West Jr., it began as a small oil and gas company in San Antonio, Texas. Over the years, Tesoro grew into a Fortune 100 company, largely through acquisitions and expansions. In 2017, Tesoro changed its name to Andeavor to better reflect its broader energy operations. The company was acquired by Marathon Petroleum in 2018, in a significant transaction that further consolidated the U.S. refining sector.

History

Tesoro was established in 1968, focusing initially on petroleum exploration and production. The company's first refinery, purchased in 1969 in Kenai, Alaska, marked its entry into the refining business. This strategic shift towards refining and marketing was pivotal in Tesoro's growth trajectory. Through the 1990s and 2000s, Tesoro expanded its refining capacity and operational footprint by acquiring several refineries across the Western United States. Notable acquisitions included refineries in North Dakota, Utah, and California, which allowed Tesoro to increase its market share and influence in the petroleum industry.

In the 2010s, Tesoro continued to grow, both organically and through acquisitions. It acquired BP's Carson Refinery in California and broadened its logistics operations by investing in pipelines, terminals, and storage facilities. This expansion was part of Tesoro's strategy to become an integrated energy company, with a balanced portfolio of refining, marketing, and logistics operations.

Operations

Tesoro's operations were primarily focused on the refining, marketing, and logistics of petroleum products. The company owned and operated refineries in the Western United States, with a combined crude oil processing capacity of over 850,000 barrels per day. These refineries produced a variety of petroleum products, including gasoline, diesel fuel, jet fuel, and asphalt. Tesoro's marketing network included hundreds of branded retail gas stations, primarily under the Tesoro, Shell, and USA Gasoline brands.

The logistics operations of Tesoro, conducted through its subsidiary Tesoro Logistics LP, included pipelines, storage facilities, and marine terminals. These assets were crucial in transporting crude oil to its refineries and delivering refined products to the market.

Acquisition by Marathon Petroleum

In 2017, Tesoro Corporation announced its rebranding to Andeavor, a move that reflected its evolution from a regional refining company to a national leader in the energy sector. However, this new chapter was short-lived, as Andeavor was acquired by Marathon Petroleum in 2018. The acquisition was valued at approximately $23.3 billion, making it one of the largest deals in the history of the U.S. oil and gas industry. This merger significantly expanded Marathon Petroleum's refining capacity and market presence, establishing it as one of the leading energy companies in the United States.

Legacy

Tesoro Corporation's legacy is marked by its transformation from a small oil company into a major player in the American energy sector. Its strategic acquisitions and expansions played a significant role in shaping the U.S. refining landscape. Even after its acquisition by Marathon Petroleum, the strategies and operations developed by Tesoro continue to influence the industry.