Charles Nissen (c.1880[1] – 13 March 1944[2]) was a British philatelist, and stamp dealer who discovered the famous stock exchange forgery and wrote, with Bertram McGowan, the definitive book on the plating of the Penny Black.
[4] Nissen discovered the Stock Exchange Forgery of 1872-73 in 1898 when examining used stamps from telegraph forms.
It is believed that a clerk in the Stock Exchange Post Office, London, had been supplementing his income by taking the one shilling telegram fees and using forged stamps instead.
Nissen was an early member of the Fiscal Philatelic Society, and was appointed to the Roll of Distinguished Philatelists in 1923.
Nissen & Co. Limited continued after his death and enjoyed a Royal Warrant from Queen Elizabeth II as stamp dealers.