Karl Llewellyn
Karl Llewellyn was perhaps the most influential intellectual ever associated with Columbia's law school. He was one of the standard bearers of the legal realism movement, and later brought his philosophy to bear on the Uniform Commercial Code, which he drafted.
Llewellyn joined the Columbia faculty in 1925. He later married Soia Mentschikoff, one of his former students, who went on to blaze paths for women in law. When the two were offered teaching positions at UChicago in 1951, Llewellyn left Columbia, and eeked out the rest of his existence there, unproductively.