Irving Marcus, 63, a patent attorney and a former director of chemical examining operations and the pharmaceutical and organic chemistry section of the U.S. Patent Office, died of an embolism Nov. 21 at Holy Cross Hospital. He had been hospitalized for hip surgery.

Mr. Marcus, who lived in Chevy Chase, was born in Brooklyn, N.Y. He graduated from Brooklyn College and in 1939 moved to Washington, where he earned a law degree at American University.

He began his career at the Patent Office in 1941 and retired in 1974. He received the Commerce Department's Silver Medal for Meritorious Service in 1961 for his work on mechanizing a patent search system at the Patent Office. In 1968, he received the department's Gold Medal for Meritorious Service for services he rendered in advising the German government on patent matters.

Since leaving the government, he had been associated with the law firm of Oblon, Fisher, Spivak, McClelland & Maier in Arlington. He also taught patent law to foreign students and appeared as an expert witness in patent trials.

Mr. Marcus was a member of the editorial board of the "Biotechnical Law Report," the Patent Office Society, the Government Patent Lawyers Association, the Federal Executive Institute Alumni Association, the American Chemical Society and the Chemical Society of Washington.

Survivors include his wife, Sarah of Chevy Chase; two children, David, of Southfield, Mich., and Ellen, of Alexandria; a brother, Marvin, of Whitestone, N.Y.; a sister, Rita Dworkin of Brooklyn, and three grandchildren.