Dennis Keith Sullivan, who served as broadcast counsel for CBS Inc. for the last 16 years, died of complications from AIDS on Oct. 20 in Falls Church, Va. He was 50.A graduate of Georgetown U. and the U. of Texas Law School, Sullivan served in the U.S. Navy Judge Advocate General’s Corps, and was a staff attorney with the Federal Communications Commission before joining CBS. Sullivan is survived by his parents, Col. and Mrs. John L. Sullivan, five brothers and one sister. A mass will be held at 9 a.m., Nov. 9 at the Blessed Sacrament Church in Hollywood. In lieu of flowers, the family requests donations to AIDS Project Los Angeles , Memory of Dennis Sullivan, 6721 Romaine St., Los Angeles 90038.