Like his father, who was a pioneer in the independent oil industry and accepted a merger with Standard Oil, Pratt was a leading figure in the U.S. oil industry. On June 1, 1923, he was elected to replace Henry Clay Folger as head of Standard Oil Company of New York, also known as Socony (which eventually became known as Mobil). After the announcement, he was featured on the June 11, 1923 cover of "Time". In 1928, after Charles F. Meyer became president of Standard Oil of New York, Pratt became chairman of the board.