Conan O'Brien probably wishes this was a joke.

A San Diego man is claiming that Conan O'Brien stole his jokes from Twitter and then used them in his late-night talk show, "Conan."

In a lawsuit filed July 22 in California federal court, Robert Kaseberg of San Diego, California alleges that jokes he tweeted were used in O'Brien's monologues shortly after he posted them on Twitter.

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Kaseberg says he published the first joke Jan. 14 on a personal blog and on Twitter, that read: "A Delta flight this week took off from Cleveland to New York with just two passengers. And they fought over control of the armrest the entire flight."

That same day, O'Brien made a similar joke: "On Monday, a Delta flight from Cleveland to New York took off with just two passengers. Yet somehow, they spent the whole flight fighting over the armrest."

On June 9, Kaseberg tweeted: "Three streets named after Bruce Jenner might have to change their names. And one could go from a Cul-de-Sac to a Cul-de-Sackless." According to the lawsuit, O'Brien used the same joke "on or about June 9."

In another instance, Kaseberg says, he tweeted: "The Washington Monument is ten inches shorter than previously thought .... You know the winter has been cold when a monument suffers from shrinkage."

On O'Brien's show, the comic said: "Surveyors announced that the Washington Monument is 10 inches shorter than what's been recorded. Of course, the monument is blaming the shrinkage on the cold weather."

A spokesman for O'Brien said the lawsuit has no merit and declined further comment, according to The Hollywood Reporter.