 The name change, one of the most expensive in the history of the U.S. oil industry, not only involved advertisements and identifying street signs at service stations, but also gasoline pumps, product packaging, tankers, transport and delivery trucks, hundreds of smaller signs at more than 25,000 service stations, and millions of credit cards sent to account holders to replace their previous Esso/Enco cards.The corporate name change from Standard Oil of New Jersey to Exxon Corporation took effect January 1, 1973, along with the name change of domestic refining/marketing division Humble Oil and Refining Co. to Exxon USA, and the mergers of Esso Chemicals and Enjay Chemicals into Exxon Chemicals.In 1957, scientists from Humble Oil published a study tracking “the enormous quantity of carbon dioxide” contributed to the atmosphere since the Industrial Revolution “from the combustion of fossil fuels.” Exxon was aware of these findings and later researched the effect of its own company on global warming.