In fact, he's cited it as the "most ridiculous rumour" he has heard around the upcoming DC Comics movie.
Supported by Bruce Wayne's comments about good people going bad in Batman v Superman, the theory was that former Robin Jason Todd wasn't killed by the Joker, but actually became him.
The evidence included the Joker's bullet hole tattoos, which seem to match up to the marks on the Robin costume on display in the Batcave.
And Ayer also shut down those reports that Suicide Squad had been reshot to make the film funnier.
"I don't think you can do that," he said, adding that it wouldn't work just to insert jokes into a serious film.
"The movie was always funny."
Jared Leto plays the Joker in the film alongside Margot Robbie as Harley Quinn, Will Smith as Deadshot and Cara Delevingne as Enchantress.
A new theory has emerged that Ezra Miller's Flash could also make a cameo.
Suicide Squad will be released on August 5.