The firm weathered many name changes from its founding through 1955, as named partners left the firm for periods of time to serve in a number of important government positions. Among them was Emory Buckner, who left to become United States Attorney for the Southern District of New York and is often credited with remaking that office into a professional prosecutorial office by declining to appoint Assistants based on party affiliation. Partner Grenville Clark served as United States Postmaster General. Later generations of partners included John Marshall Harlan II, who left the firm when appointed to serve as a Judge of the Second Circuit Court of Appeals and who later became an Associate Justice of the United States Supreme Court; Henry J. Friendly, who left with several partners to form the firm of Cleary, Friendly, Gottlieb & Steen (now Cleary Gottlieb Steen & Hamilton LLP) and later was appointed to serve on the Second Circuit Court of Appeals.