Irving Kaplan worked in the United States Department of the Treasury and for the Foreign Economic Administration. Kaplan was the chief advisor to the Allied Military Government for Occupied Territories in Germany on financial and economic matters after 1945. He received an 'E' rating from Harold Glasser. He was associated with both the Perlo group of spies and the Silvermaster cells and was employed by David Weintraub in the United Nations Division of Economic Stability and Development from February 1946 through November 1952. The Federal Bureau of Investigation (FBI) has submitted eighteen adverse reports on Kaplan.
- Gorsky Memo: Translation of KGB file 43173 vol. 2 (v) pp. 46-55.
- Allen Weinstein and Alexander Vassiliev, The Haunted Wood: Soviet Espionage in America--the Stalin Era (New York: Random House, 1999)