Dustin Lance Black slams Sam Smith after Oscar win

Sam Smith claimed to be the first openly gay man to win an Oscar on Sunday night during his acceptance speech for Best Original Song for "Writing's On The Wall" from the most recent James Bond film, "Spectre."

The only problem, of course, is that his claim was completely incorrect.

Elton John, Bill Condon and Stephen Sondheim, among many other openly gay men, have also won Academy Awards.

SEE ALSO: Sam Smith dedicates his Oscar to LGBT community

Smith misquoted Sir Ian McKellen, who said in January that an openly gay man had never won in the lead actor category, and at least one of those former winners slammed him for his mistake.

Dustin Lance Black, who won for Best Original Screenplay for "Milk" in 2008, called Smith out on Twitter, saying, "Hey @SamSmithWorld, if you have no idea who I am, it may be time to stop texting my fiancé," which he followed with a link to his emotional acceptance speech from eight years ago.

Black's fiancé is British Olympic diver Tom Daley.

The diss quickly went viral, and by press time had over 5,000 retweets.

See photos from inside the 2016 Oscars:

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