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https://en.wikipedia.org/wiki/Autopen
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US Presidents""
""It has long been known that US Presidents use multiple autopen systems to sign many official documents (e.g., military, diplomatic, and judicial commissions; some Acts of Congress, executive directives, letters and other correspondence), due to the volume of such documents requiring their signature per the US Constitution. Some say Harry Truman was the first president to use the autopen as a way of responding to mail and signing checks.[12] Others credit Gerald Ford as the first president to openly acknowledge his use of the autopen,[13] but Lyndon Johnson allowed photographs of his autopen to be taken while he was in office, and in 1968 the National Enquirer ran them along with the front-page headline "The Robot That Sits In For The President.""
""In
March 2025, President Trump declared that pardons for members of the House Select Committee on the January 6 Attack issued during Biden's presidency are void due to them allegedly being signed by autopen.
However, in 2024, the Fourth Circuit Court of Appeals ruled that pardons do not have to be in writing.""