Conan O’Brien makes an appearance at Harvard University on Feb. 12, 2016. (Charles Krupa/AP)

U.S. District Court Judge Janis Sammartino recently refused to toss out an unusual lawsuit accusing late-night host Conan O’Brien and his writing staff of stealing jokes from a professional joke writer’s blog and Twitter feed, claiming some were entitled to “thin copyright protection.”

Robert “Alex” Kaseberg, a writer who has penned more than 1,000 jokes for Jay Leno, accused O’Brien of telling five of his jokes in his monologue on “Conan.” Kaseberg said he wrote and posted the jokes online between Dec. 2, 2014, and June 9, 2015.

Kaseberg wrote on his blog he was convinced O’Brien’s team was stealing his material after the third time he heard the comedian tell a joke he had recently posted.

“Two times there is an impossibly slight possibility of a joke-writing coincidence, three times there is no possibility of a coincidence,” he wrote. “And always used on the monologue one day or, in the case of the third time, six hours after it appeared on my blog and or Twitter.”

Kaseberg said he reached out to O’Brien’s writing team but was rebuked. He then filed suit against O’Brien, his writing staff, Turner Broadcasting and Time Warner in July 2015. O’Brien and the other parties denied any joke theft and requested that the case be dismissed.

In her opinion issued Friday, the judge allowed the suit to proceed to trial but threw out two jokes. The suit will proceed on the other three.

The judge noted the difficulty of proving that a joke was stolen.

“Facts, of course, are not protected by copyright,” she wrote. “And although the punchlines of the jokes are creative, they are nonetheless constrained by the limited number of variations that would (1) be humorous (2) as applied to the specific facts articulated in each joke’s previous sentence and (3) provide mass appeal. This merits only thin protection.”

Because of such “thin protection,” there has not been an intellectual property lawsuit concerning comedy in “decades and decades,” New York University law professor Christopher Sprigman told USA Today.

“Comics rarely sue one another, and to some degree this case illustrates why,” he added. “The judge ruled the case could go forward but the ruling makes it difficult” for Kaseberg to win.

Even so, Kaseberg’s lawyer, Jayson Lorenzo, called the ruling “a victory for comedy writers, especially lesser known writers,” in a statement to the New York Times.

The three jokes in question, according to court documents:

The Tom Brady joke

  • Kaseberg: “Tom Brady said he wants to give his MVP truck to the man who won the game for the Patriots. So enjoy that truck, Pete Carroll.”
  • O’Brien: “Tom Brady said he wants to give the truck that he was given as Super Bowl MVP … to the guy who won the Super Bowl for the Patriots. Which is very nice. I think that’s nice. I do. Yes. So Brady’s giving his truck to Seahawks coach Pete Carroll.”

The Caitlyn Jenner joke

  • Kaseberg: “Three towns, two in Texas, one in Tennessee, have streets named after Bruce Jenner and now they have to consider changing them to Caitlyn. And one will have to change from a Cul-De-Sac to a Cul-De-Sackless.”
  • O’Brien: “Some cities that have streets named after Bruce Jenner are trying to change the streets’ names to Caitlyn Jenner. If you live on Bruce Jenner Cul-de-sac it will now be Cul-de-no-sack.”

The Washington Monument joke

  • Kaseberg: “The Washington Monument is ten inches shorter than previously thought. You know the winter has been cold when a monument suffers from shrinkage.”
  • O’Brien: “Yesterday surveyors announced that the Washington Monument is ten inches shorter than what’s been previously recorded. Yeah. Of course, the monument is blaming the shrinkage on the cold weather.”

“The only consolation I can take from this horrifying violation is I wrote three jokes that were good enough to be on the monologue on ‘Conan.’ And they all got good laughs,” Kaseberg wrote on his blog in 2015. “Since I cannot watch the show again — it is too painful — and I have lost respect for one of my comedy idols, that consolation will have to be enough.”

O’Brien also appeared to be emotionally affected by the situation.

“Accusing a comedian of stealing a joke is the worst thing you can accuse them of, in my opinion, short of murder,” O’Brien said during a deposition in the case, according to the Hollywood Reporter. “I think it’s absolutely terrible.”

The trial is on pace to take place in August, CBS reported.

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