We make it a policy not to comment on frivolous or meritless claims

Michael Gendler Lawyer for David Chase

The show has been a massive success in both the US and UK, gaining awards and viewers for its portrayal of a gang boss who is in therapy and his complicated family and "business" life.

Mr Baer says he had suggested a TV show about gangsters in New Jersey and met repeatedly with Chase to fill him in on organised crime in North Jersey.

The judge says he even reviewed an early draft of the pilot episode for Mr Chase.

He says he had an oral agreement with Mr Chase that if the show was successful, Mr Baer would be "appropriately compensated".

'Invaluable contribution'

But after the show was sold to the HBO US cable network and became a success, Mr Baer says he was excluded.

"My client is responsible for the concept of The Sopranos," Mr Baer's lawyer, Harley Breite said.

"But for his invaluable contributions, there would be no Sopranos."

The cast is mainly Italian American

But Mr Chase's lawyer Michael Gendler said: "We make it a policy not to comment on frivolous or meritless claims."

Mr Baer met Mr Chase in 1995 through a mutual friend, Joseph Urbanczyk, who has known Mr Baer since they were children.

Mr Urbanczyk, a camera operator in Hollywood, described the conflict between the men as "a very ugly situation" and said Mr Chase turned his back on Mr Baer when he found success.

The legal action asserts that during a three-hour lunch in Santa Monica, California, Mr Baer recounted stories of gangsters in northern New Jersey to Mr Chase, and suggested that they set the series in a town called Elizabeth.

Phone calls

"That's the reason why on the opening credits, you see the turnpike sign for the Elizabeth exit," Harley Breite said.

Many of the show's outdoor shots were filmed in Elizabeth's predominantly Italian Peterstown area.

The legal action says Mr Chase later made dozens of phone calls to Mr Baer at his home to ask questions about the mob in New Jersey.

It says Mr Baer still has the copy of a script he read and reviewed for Mr Chase.

Harley Breite said Mr Baer tried several times to contact David Chase after the show was sold to HBO.