Forgery as covert operation Forgery is used by some governments and non - state actors as a tool of covert operation , disinformation and black propaganda . Letters , currency , speeches , documents , and literature are all falsified as a means to subvert a government ’ s political , military or economic assets . Forgeries are designed to attribute a false intention and aspirations on the intended target . They force the targeted government to spend a large amount of resources to refute the forgery . Forgeries are an effective tool because of their ability to hold influence even after being proven false . Techniques . Counterfeit money . Counterfeiting is the creation of currency without the official sanction of the issuing state or government . It is designed to look like the real currency and convince others of its value . Counterfeiting has been used as a tactic to increase individual wealth since the creation of currency itself . Counterfeit money has also been used as a covert operation by rival nations in an attempt to create inflation and subvert . Counterfeiting is a useful tool of subversion because it results in a reduction in the value of real money ; an increase in prices ( inflation ) due to more money getting circulated in the economy - an unauthorized artificial increase in the money supply ; a decrease in the acceptability of paper money ; and losses , when traders are not reimbursed for counterfeit money detected by banks , even if it is confiscated . Operation Bernhard . Operation Bernhard was a counterfeit campaign conducted by the Nazi regime to flood the United Kingdom with £5 and £50 banknotes . The scale of the counterfeit campaign was the largest ever conducted since the advent of paper money . The original plan was to introduce the counterfeit money into Great Britain to create inflation , but this plan was abandoned due to diplomatic issues . Rather , the counterfeit notes were used to finance war expenses . The counterfeited notes were created at the Sachsenhausen concentration camp by prisoners who were experts in forgery . Philatelic forgeries . Philatelic forgery is the creation of false postage stamps that are designed to look genuine . Because of their wide publication , stamps are a powerful tool of propaganda . Forged stamps were used by both the Allies and Axis Powers during World War II . Large philatelic campaigns were also conducted throughout the Cold War . Literary forgery . Literary forgery is a body of written work attributed to a certain eminent , historical or popular author . This forgery is often a fake manuscript or diary created to attribute certain ideological beliefs or actions to the figure . Literary forgery is often difficult to refute because the purported author is usually deceased . United States Secret Service . The United States Secret Service is the agency within the United States ' government tasked with the protection of U . S . currency . The Secret Service has jurisdiction over violations involving the counterfeiting of United States obligations and securities . Some of the counterfeited United States obligations and securities commonly investigated by the Secret Service include U . S . currency ( to include coins ) , U . S . Treasury checks , Department of Agriculture food coupons and U . S . postage stamps . The United States Secret Service was created by Abraham Lincoln during the Civil War in 1865 to combat the high counterfeit rate of currency . At the time , one - third to one - half of all U . S currency in circulation was counterfeit . Today , the Secret Service continues its core mission by investigating violations of U . S . laws relating to currency , financial crimes , financial payment systems , computer crimes and electronic crimes . It utilizes investigative expertise , science and technology , and partnerships to detect , prevent and investigate attacks on the U . S . financial infrastructure .