The use of the autopen, a device that reproduces signatures and is ubiquitous in government and business, is ordinarily uncontroversial. There is no power to undo a pardon in the Constitution or case law.

Donald Trump says Joe Biden's last-minutes pardons via autopen are null and void. But what is an autopen? And what does it mean for pardons?

In a post on Truth Social overnight, President Donald Trump claims that some pardons by President Joe Biden are “VOID, VACANT, AND OF NO FURTHER FORCE OR EFFECT,” saying an autopen was used to forge the former President’s signature.