Claim: Capt. Sir Mansfield Cumming suggested that British intelligence agents use semen as invisible ink during World War I, but later put a stop to it due to the smell.
Fact-check: Did Capt. Cumming Suggest Semen as Invisible Ink in WWI?
Verdict: true
Organisation: Snopes
Author: Jordan Liles
Date published: 2022-01-13T14:00:00