Shell Oil Company is the United States-based wholly owned subsidiary of Royal Dutch Shell, a multinational "oil major" of Anglo-Dutch origins, which is amongst the largest oil companies in the world. Approximately 22,000 Shell employees are based in the U.S. The U.S. headquarters are in Houston, Texas. Shell Oil Company, including its consolidated companies and its share in equity companies, is one of America's largest oil and natural gas producers, natural gas marketers, gasoline marketers and petrochemical manufacturers.
Shell is the market leader through approximately 25,000 Shell-branded gas stations in the U.S. which also serve as Shell's most visible public presence. At its gas stations Shell provides diesel fuel, gasoline and LPG. Shell Oil Company was a 50/50 partner with the Saudi Arabian government-owned oil company Saudi Aramco in Motiva Enterprises, a refining and marketing joint venture which owns and operates three oil refineries on the Gulf Coast of the United States. However, Shell is currently divesting its interest in Motiva.
Shell products include oils, fuels, and car services as well as exploration, production, and refining of petroleum products. The Shell Oil Refinery in Martinez, California, the first Shell refinery in the United States, supplies Shell and Texaco stations in the West and Midwest.
In 1997, Shell and Texaco entered into two refining/marketing joint ventures. One combined their Midwestern and Western operations and was known as Equilon. The other, known as Motiva, combined the Eastern and Gulf Coast operations of Shell Oil and Star Enterprise, itself a joint venture between Saudi Aramco and Texaco.
After Texaco merged with Chevron in 2001, Shell purchased Texaco's shares in the joint ventures. In 2002, Shell began converting these Texaco stations to the Shell brand, a process that was to be completed by June 2004 and was called "the largest retail re-branding initiative in American business history.". In the year 2016, Shell Nederland Raffinaderij BV (Shell Pernis) said that it has started a new aromatics unit at the large Pernis refinery in Rotterdam, Netherlands.
In recent years The Shell Oil Company's Midstream, and Downstream, in particular, have become limited to petroleum, and chemical products. This has come as a result of Royal Dutch Shell breaking off its Natural Gas and power businesses in to a new segment named Integrated Gas. The Shell Oil Company's former Natural Gas, and energy divisions are now Shell Energy North America, a closely integrated, but distinctive entity that runs across North America and is headquartered out of Houston.
Until the mid-1980s Shell's business in the United States was substantially independent. Limited direct involvement from the main office in The Hague, Netherlands and having its stock "Shell Oil" traded on the New York Stock Exchange were factors. However, in 1984, Royal Dutch Shell made a bid to purchase those shares of Shell Oil Company it did not own (around 30%) and despite some opposition from some minority shareholders which led to a court case, Shell completed the buyout for a sum of $5.7 billion.
Despite the acquisition, however, Shell Oil remained a fairly independent business. This was due in part to complex legal reasons as Royal Dutch Shell feared that there could be onerous liability problems if a closer control of Shell Oil's affairs was exercised by the "parent company." One consequence of this independence was that the Shell logo used in the U.S. was slightly different from that used in the rest of the world. In the 1980s Shell Oil's independence began to gradually erode as the "parent company" took a more hands-on approach in running the business. The logo used in the United States is the same as that used elsewhere since June 1, 1998.
Shell has companies in North, South and Central America: in Argentina, Aruba, Barbados, the Bahamas, Bolivia, Brazil, Canada, Chile, Colombia, Costa Rica, The Dominican Republic, Ecuador, Guatemala, Honduras, Mexico, Nicaragua, Panama, Peru, Puerto Rico, Suriname, Trinidad and Tobago, Uruguay, the U.S. and Venezuela. Shell also has companies in Africa, Europe, the Middle East, and Asia.
Shell Puget Sound Refinery, Anacortes, Washington, was fined $291,000 from 2006 to 2010 for violations of the Clean Air Act making it the second most-fined violator in the Pacific Northwest. As of 2011[update], it was listed as "high priority violator" since 2008.
In 2008, a lawsuit was filed against Shell Oil Company for alleged Clean Air Act violation. Shell Deer Park facility, 20 miles east of Houston, was the nation's eighth-largest oil refinery and one of the world's largest petrochemical producers. The facility was also the second largest source of air pollution in Harris County, which ranked among the lowest in the nation in several measures of air quality.[News 1] According to Sierra Club and Environment Texas, analysis of Shell's reports to the Texas Commission on Environmental Quality, air pollutants released at Deer Park since 2003 exceeded the EPA's emissions limits.
Will Oremus from Slate magazine states, "The company's business depends on being able to anticipate and respond quickly to seismic shifts in the energy market. So it employs a team of big-thinking futurists, called scenario planners, to keep it a step ahead. In 2008 the company released a fresh pair of scenarios for how the world might respond to climate change over the coming decades. Both were predicated on what the company called 'three hard truths': that global energy demand is rising, that the supply of conventional energy will not be able to keep up, and that climate change is both real and dangerous." 
Between 1978 and 1995, Shell Oil produced polybutylene pipes, which corrode when exposed to chlorine. A class action lawsuit was filed in 1995 against Shell Oil when the polybutylene pipes caused flooding in many households in the U.S. and Canada. The settlement required Shell Oil to pay for the re-installation of piping for millions of houses for claims filed through May 2009.