I copied this from Wikipedia, but it should be fairly accurate in answering your question.
"British Petroleum merged with Amoco (formerly Standard Oil of Indiana) in December 1998, becoming BPAmoco until 2000 when it was renamed BP and adopted the tagline "Beyond Petroleum," which remains in use today. It states that BP was never meant to be an abbreviation of its tagline. Most Amoco petrol stations in the United States have changed the look and name to the BP brand. In many states, however, BP is selling Amoco branded gasoline, as it was rated the best petroleum brand by consumers 16 years in a row (the name of the service station itself is still BP) and Amoco has one of the highest brand loyalty for gasoline in the US with only Chevron and Shell having such high rates as BP/Amoco. In May 2008, however, the Amoco name was mostly phased out in favour of "BP Gasoline with Invigorate", promoting BP's new additive. The highest grade of BP gasoline available in the United States is still called Amoco Ultimate, however. In 2000, British Petroleum acquired Arco (Atlantic Richfield Co.) and Burmah Castrol plc."
I guess by buying Amoco they were allowed to drill and pump off our coast.
British Petroleum:
Our brands:
BP
Castrol
Arco
Aral
am/pm
Wild Bean Cafe
Shell: Shell is a global group of energy and petrochemical companies. Our headquarters are in The Hague, the Netherlands, and our Chief Executive Officer is Peter Voser. The parent company of the Shell group is Royal Dutch Shell plc, which is incorporated in England and Wales.
Shell by numbers
+ 90 countries where we operate
~101,000 number of employees
2% amount of world’s oil we produce
3% amount of world’s gas we produce
3.1 million barrels of gas and oil we produce every day
44,000 Shell service stations worldwide
145 billion litres of fuel sold
>35 refineries and chemical plants we run (figures for 2009)
1 ranking by Fortune 500 in 2009
ConocoPhillips:
ConocoPhillips traces its beginnings to 1875, when Conoco founder Isaac E. Blake envisioned an idea to make kerosene available and affordable to townspeople in Ogden, Utah. Thirty years later, the foundation for Phillips Petroleum Company began when brothers Frank and L.E. Phillips hit the first of 81 wells without a dry hole. Nearly a century later, the two companies combined their strengths to form what is now the third-largest energy company in the United States. The ConocoPhillips merger, completed on Aug. 30, 2002, paved the path for the company’s current and future success.
In 2006, Burlington Resources joined ConocoPhillips. The acquisition brought Burlington’s more than 100 years of experience to ConocoPhillips and enhanced the company’s position as a leading producer and marketer of natural gas. In recent years, ConocoPhillips began commercial production of renewable diesel fuel, started the first Alpine satellite oil field, announced plans for a global water sustainability center and formed a partnership with Tyson Foods, Inc. to produce next-generation renewable diesel fuel. While ConocoPhillips’ history still is young, the histories of Conoco, Phillips and Burlington provide a solid foundation for ConocoPhillips to leave a mark on the industry.
Conoco Inc.:
Conoco Inc. began in 1875 as the Continental Oil and Transportation Co. Based in Ogden, Utah, the company distributed coal, oil, kerosene, grease and candles to the West.
Phillips Petroleum Company:
Phillips Petroleum Company traces its roots to Bartlesville, Okla., in the middle of Indian Territory. In 1905, Frank Phillips and brother, L.E. hit their first gusher, the first of 81 wells in a row without a single dry hole.
Burlington Resources:
The seeds for Burlington Resources were planted in 1864 when U.S. President Abraham Lincoln granted to Northern Pacific Railway Company, predecessor to Burlington Northern Railroad Company, land and right-of-way to build a transcontinental railroad.
Sinclair"
A proud tradition was born on May 1, 1916, when Harry Sinclair formed Sinclair Oil from the assets of eleven small petroleum companies. Sinclair quickly grew to become the seventh largest oil company in the United States. The original Sinclair Oil Company began marketing the apatosaurus (brontosaurus) in 1930 and now after more than 70 years, "Dino" still remains one of the most recognizable corporate logos in the world.
Sinclair is headquartered in Salt Lake City, Utah, and is the nucleus of a corporation that includes Snowbasin Resort in Ogden, Utah (site of the 2002 Downhill Courses), as well as Sun Valley Resort in Idaho. One of the most prominent properties of Sinclair is Little America, a beautiful hotel, travel center and restaurant located on I-80 in western Wyoming.
Maybe we should be buying from ConocoPhillips and Sinclair if we want to support American companies and American workers.
(I do not work for, or own stock in either company. Just saying .....)