Fans couldn't hold back and were quick to correct Osher, tweeting that other Australians had actually written for Queen Bey too.
"Deni's the only Australian to write a song for Beyonce? Ummm, Pretty Hurts by Sia much?" one fan tweeted.
"Did @oshergunsberg just say Deni was the only Australian to write a song for Beyonce like @sia hasn't been in her basement for years," said another.
And it didn't stop there.
Another fan tweeted: "Deni isn't the only Australian to have written for Beyoncé" alongside a Wikipedia entry for her song Rather Die Young, which was co-written by Australian Luke Steele, of the band Empire of the Sun.
Perhaps Channel Ten will employ fact checkers for Osher ahead of the next The Masked Singer episode.