Outside of law and academia, Sovern was president of the Shubert Foundation and served on numerous boards, including Comcast Communications, the Shubert Organization, the Asian Cultural Council, and Atlantic Philanthropies. He served as chairman of Sotheby's Holdings, Inc.from 2000 to 2012, American Academy in Rome from 1994 to 2005, the Japan Society from 1993 to 2005, and the National Advisory Council for the Freedom Forum Media Studies Center. He was a member of the board of the NAACP Legal Defense Fund, the Kaiser Family Foundation, the Pulitzer Prizes, AT&T, Pfizer, Warner–Lambert and JP Morgan Chase, among others.