The story
Founded by Robert V. West Jr. in 1968.1
Tesoro was founded in 1968 by Dr. Robert Van Osdell West Jr (1921–2006), and was primarily engaged in petroleum exploration and production. Tesoro began operating its first refinery, near Kenai, Alaska, in 1969. Tesoro became the first Fortune 500 company to be headquartered in San Antonio, Texas.
Tesoro is the word for treasure (or treasury) in Italian and Spanish.
Beginning in the late 1990s, Tesoro grew through a series of acquisitions and initiatives that created Tesoro Corporation, the company focusing on the core business of petroleum refining, marketing, maritime transportation and distribution. The first segment involved the operation of six petroleum refineries situated in California, Alaska, Washington, Hawaii, North Dakota, and Utah. For its marketing and distribution segment, Tesoro sold refined gas and fuel products in both bulk and wholesale markets. Acquisitions expanded refining capacity from 72,000 barrels per day (11,400 m3/d) to approximately 664,000 barrels per day (105,600 m3/d).
Prior to its acquisition by Marathon Petroleum in 2018, Tesoro was the third-largest independent petroleum refining and marketing company in the United States. The merger between the two companies formed the largest American refiner by capacity and the fifth in the world.
Milestones in Tesoro's history are:
1998: acquires second refinery (after Nikiski) in Kapolei, Hawaii along with petroleum terminals and approximately 30 retail stations in Hawaii from BHP Americas — also acquires the former Shell refinery at Anacortes, Washington;
1999: sells exploration and production operations;
2001: purchases refineries in Mandan, North Dakota, and Salt Lake City, Utah from BP Amoco;
Read the full text
2002: acquires Golden Eagle Refinery in Martinez, California from Ultramar (Valero);
2003: sells Tesoro Marine Services to Martin Midstream: Tesoro Marine Services were operating fueling and supply terminals servicing US Gulf Coast oil and gas exploration — also made a series of refinery acquisitions that boosted the company's capacity output and positioned it for future expansion in key growth markets throughout the Western United States;
2005: largest capital expansion program in Tesoro Corporation's history and record earnings;
2007: announcement of purchase of Shell's refinery at Los Angeles refinery and approximately 250 Southern California retail stations;
2007: Tesoro acquires USA Gasoline;
2009: Tesoro employees move into a newly completed corporate campus in July;
2011: Tesoro forms Tesoro Logistics LP (TLLP) as a master limited partnership;
2011: Tesoro acquires 250 ARCO (Thrifty Style Stations) and Thrifty Stations in Southern California;
2012: Tesoro changes the 250 ARCO (Thrifty Style Stations) and Thrifty Stations in Southern California to USA Gasoline;
2013: Tesoro purchases the Carson refinery and the ARCO brand from BP;
2013: Tesoro sells its Kapolei refinery to Par Petroleum (now Par Pacific Holdings);
2016: Tesoro purchases Dakota Prairie Refining in Dickinson, North Dakota from WBI Energy; construction of the refinery was completed in the spring of 2015;
2016: Tesoro Corp agrees to buy Western Refining for $4.1 billion;
2016/17: Par Pacific Inc. rebrands its Tesoro and 76 gas stations as HELE;
2017: Tesoro announces its change of name to Andeavor following its acquisition of Western Refining; On August 1, 2017, the company changed its ticker symbol to "ANDV" from "TSO";
2018: Andeavor announced its entering into a definitive merger agreement with Marathon Petroleum with Marathon Petroleum acquiring all of Andeavor's outstanding shares for US$23 billion (equivalent to $28.2 billion in 2024); the merger was closed on October 1.
From Wikipedia’s article on Tesoro Corporation, shared under CC BY-SA 4.0.7