Gloves come off in bloody battle for the rights to film Raging Bull II

MGM studio files lawsuit asking courts to halt production of sequel to classic boxing film

The original 'Raging Bull' starred Robert DeNiro. It was based on the life of Jake LaMotta

Legal punches have been flying this week between the makers of a low-budget sequel to the classic 1980 biopic Raging Bull, made by Martin Scorsese and starring Robert DeNiro, with MGM, the studio that made the original, asking the courts that production be halted and the project binned.

In the ring with MGM is Jake LaMotta, the 90-year-old former boxing legend on whose rise and fall in the 1950s the Raging Bull epic was based, and the production company he has tied himself to make Raging Bull II. It is appropriately called RBII Production. Filming is already almost completed with a cast that includes Paul Sorvino, Joe Mantegna and the character actor William Forsythe.

The suit, filed in a Los Angeles court this week, asserts that Mr LaMotta remains under a contractual obligation to offer first refusal for the rights to his book, Raging Bull II, which he co-wrote in 1986 as a follow up to his original autobiography to MGM. It wants a jury to order a halt to production and a prevent distribution of the new film assuming it ever gets finished.

For Mr LaMotta the suit is clearly an unwelcome blow. "How can you fight a company that big?" he complained to the New York Post, adding, "All of these business things, I don't bother with it because I'm not capable, physically or mentally, because I don't hear so good."

"LaMotta and the RBII defendants are publicly associating the Sequel Picture with the [original] in a manner that is plainly calculated to create confusion in the marketplace and to trade off the value of the [original]," MGM's attorney says in the complaint, which alleges breach of contract, tortious interference, and unfair competition. MGM is seeking the rights to the follow-up book and monetary damages.

Should the court action succeed, it isn't clear that the loss to cinema fans – including those who still recall being stirred by the first Raging Bull and Mr De Niro's acting in it – will be big. The director has been identified by Entertainment Weekly as Martin Guigui, whose portfolio includes My X-Girlfriend's Wedding Reception and National Lampoon's Cattle Call, a record, the magazine sarcastically observed, that "makes him the ideal guy to helm a sequel to one of the great films of the 20th century".

The battle over Raging Bull and its potential offspring is not entirely new. The daughter of the late Peter Savage (real name Patrella), who co-wrote the two biographies with LaMotta, filed her own suit against MGM in 2009 trying to take back ownership rights of the boxer's biographies. She failed.

Mr LaMotta, who is being played by Forsythe in the new film, told the Post it had a modest budget by Hollywood standards – $13m (£8.3m) – and was almost ready for editing. He blamed the producers for failing to settle the right matter before starting to shoot.

Mr Scorsese for now seems eager not to get involved in the latest courtroom bout. Asked by GQ magazine recently what he thought of it all, he replied: "Oh, nothing I could say about it except I don't think I could revisit the material, as they say. I think we said what we had to say at the time. All of us moved on."