Donald Trump's 'Stable Genius' Tweet Sparks Rush to Sell Merch

The true "stable genius" might not be President Trump ... instead it's the people cashing in on 45's latest catchphrase.

According to the U.S. Patent and Trademark Office, 3 people have already applied for rights to slap "stable genius" all over apparel. Problem is ... only one can own the rights to put it on clothes.

We spoke to Jeremy Joseph, the second guy to submit his application, who told us he jumped at the chance because he thought Trump's "unintended irony" could be a powerful statement.

The USPTO handles applications on a first-come, first-serve basis, so Jeremy might be S.O.L. if the applicant before him is approved. The third applicant wants a "stable genius covfefe" trademark for a coffee line ... so he's not competing with the other 2.