President Donald Trump has claimed that pardons signed by his predecessor Joe Biden are invalid. His reasoning: They were allegedly signed with an autopen, a signing machine used by the U.S government for decades.

President Donald Trump raised eyebrows Monday by claiming that pardons issued by President Joe Biden are “invalid” because they were signed using an autopen, an electronic device that replicates a person’s signature.

The president has recently made baseless claims that Joe Biden routinely used an autopen and that his unelected aides used the executive power of the presidency without his knowledge.