Seymour Friedman, 70, an attorney who retired in 1980 as executive vice president and general counsel of Dominion Holdings Inc. and the Northampton Corp., land development and management firms, died Dec. 13 at George Washington University Hospital. He had undergone surgery for a brain tumor.

Mr. Friedman, who lived in Chevy Chase, was born in New York City. He graduated from the City College of New York and earned a law degree at Columbia University, where he was an editor of the Law Review.

He moved to Washington in 1938 as an attorney with the Railroad Retirement Board. During World War II, he was assistant general counsel of the Office of Price Administration. He later worked for the Agriculture Department and then went into a private law practice.

From 1954 to 1961, he was vice president and general counsel of Carl Freeman Inc., a building firm. He then returned to private practice until 1969, when he joined Dominion Holdings and Northampton.

Since retiring, Mr. Friedman had been active in the American Arbitration Association and was chairman of the Maryland Health Claims Arbitration Office.

He was a member of the Friends of the National Symphony and the National Lawyers Club.

Survivors include his wife, Marcia of Chevy Chase; two children, Ellen Finkelstein of Baltimore, and Jonathan of Richmond, and two grandchildren.