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. head office is 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.