Facebook founder Mark Zuckerberg is taking Shakespeare's phrase "let's kill all the lawyers" to a different level. On Monday, he sued many of the attorneys who represented a New Yorker named Paul Ceglia, the man who claimed Zuckerberg promised him half of Facebook back when Zuckerberg was an 18-year-old Harvard University student.

"The lawyers representing Ceglia knew or should have known that the lawsuit was a fraud—it was brought by a convicted felon with a history of fraudulent scams, and it was based on an implausible story and obviously forged documents. In fact, Defendants’ own co-counsel discovered the fraud, informed the other lawyers, and withdrew. Despite all this, Defendants vigorously pursued the case in state and federal courts and in the media," Facebook said in a New York Supreme Court suit.

Further Reading The other strange tale of Facebook’s disputed origins

Zuckerberg and Ceglia met in 2003, when Ceglia was one of Zuckerberg's freelance clients. Ceglia hired the future Facebook founder via a Craigslist ad, and his job was to perform programming work for Ceglia's former online venture, StreetFax. The venture provided photographs of intersections to insurance adjusters.

According to Ceglia's lawsuit, as part of the so-called "work for hire" contract, Zuckerberg agreed to provide Ceglia with at least a 50-percent Facebook stake, and Ceglia fronted Zuckerberg $1,000 to make it happen. The contract references a project called "The Face Book" in one place and "The Page Book" elsewhere. At least that's Ceglia's position, according to the contract he submitted to the courts [PDF]. He sued Facebook and Zuckerberg in 2010, demanding the New York federal courts enforce the contract. Along the way, he produced e-mails between himself and Zuckerberg that seemingly bolstered his position. He went through a turnstile of attorneys litigating his claims, however.

US Attorney Preet Bharara of the Southern District of New York charged Ceglia criminally in 2012 and said Ceglia's lawsuit was a "quick payday based on a blatant forgery" baked in "false evidence." Ceglia's lawsuit was dismissed, and the judge presiding over it said it was "predicated on a fabrication [PDF] and that plaintiff knows it."

Zuckerberg's lawsuit, meanwhile, says the lawyers were pursuing the matter in hopes of an out-of-court settlement. The suit accuses them of "malicious prosecution and deceit and collusion with intent to deceive the court."

The lawsuit said Ceglia's original counsel circulated a pitch document to "multiple top tier law firms that described the lawsuit and sought their help in furthering a scheme to force Facebook and Zuckerberg into an early high-value settlement."

The lawsuit, which names nine lawyers and several law firms, accuses one of the nation's biggest, DLA Piper, of publicly staking "its reputation on the veracity of Ceglia's allegations."

"One of DLA Piper's most senior lawyers told The Wall Street Journal that he has spent weeks investigating Ceglia's evidence and was '100 percent' certain that the forged contract was authentic," the lawsuit said.

DLA Piper, for its part, said it was involved with the lawsuit for nearly three months.

"This is an entirely baseless lawsuit that has been filed as a tactic to intimidate lawyers from bringing litigation against Facebook,” Peter Pantaleo, the firm's general counsel, said in a statement.

Facebook said in a statement that it is suing because the lawyers "should be held to account."

"We said from the beginning that Paul Ceglia’s claim was a fraud and that we would seek to hold those responsible accountable,” Colin Stretch, Facebook's general counsel, said in a statement. “DLA Piper and the other named law firms knew the case was based on forged documents yet they pursued it anyway, and they should be held to account.”

No court date was immediately set.