Autopen

But most offices either use autopens with the boss's name or simply have a staff member sign the boss's name to the correspondence.

Source: wiktionary

An autopen is a machine that copies a person's signature and then reproduces it at a rate many times faster than could normally be done - some top celebrities even have several autopens with slightly altered autographs, making it even more difficult to tell which is the real thing.

Source: wiktionary

Many executive orders signed by Mr. Biden were approved with an autopen device, prompting questions about whether Mr. Biden was fully mindful of what was signed during his presidency.

Source: wiktionary

President Donald Trump’s presidential memorandum ordering an investigation of Joe Biden’s cognitive decline and his use of the autopen […] is also nonsensical fan service, amplifying addled MAGA conspiracy theories that contend, with a straight face, that Biden was really a robotic clone.

Source: wiktionary