What was the name of John D. Rockefeller's oil company?

In 1870, John D. Rockefeller joined the oil business with his brother William, Samuel Andrews, Henry M. Flagler, and Stephen V. Harkness. Rockefeller formed the Standard Oil Company on January 10, 1870, with his business partners and brother. The success of this business empire made Rockefeller one of the world's first billionaires and a celebrated philanthropist. He garnered both admirers and critics during his lifetime and after his death.

Source: Library of Congress