In another submission, Yann Lecun says they did not sign this letter. https://news.ycombinator.com/item?id=35353484 https://news.ycombinator.com/item?id=353534

In another submission, Yann Lecun says they did not sign this letter. https://news.ycombinator.com/item?id=35353484 https://news.ycombinator.com/item?id=35353484 and in a reply to that tweet, someone points out that "Xi Jinping" had also signed the letter. So it seems that the supposed signatories are not verifiable and many of them might be faked. The Reuters editors seem to have done not even a basic verification on this story.