Medical supply company, Boston Scientific, is using "tortuous" and "fallacious" arguments to justify a secret Dublin plant it set up to copy a key supplier's heart manufacturing equipment, a Manhattan judge has ruled. Sean O'Driscoll reports from New York

Judge Alvin K. Hellerstein struck out Boston Scientific's defences and ruled that the case could proceed to a jury to decide how much damages the supplier, Medinol, was entitled to receive.

The justice compared the behaviour of Boston Scientific to a man who marries a woman for her money and then complains about the marriage contract when he discovers she is not as rich as he thought she was.

It emerged earlier this year that Boston Scientific had set up the secret operation at a plant in Sandyford Industrial Estate in Dublin to copy a heart device manufacturing machine used by Medinol.

The Israeli company supplied Boston Scientific with coronary stents, devices used to keep heart valves open.

The multimillion-euro clandestine operation, which was set up in 1997, was uncovered when a US Department of Justice investigation into Boston Scientific on a separate matter "tripped over" the operation while examining documents at its Galway manufacturing plant, according to a memo that was sent by the company's chief executive, Mr Jim Tobin, to the board of Boston Scientific.

It emerged that Boston Scientific had set up a company called Forwich, to disguise the copying of a coronary stent manufacturing machine and had used a "shell headquarters" for Forwich in Dublin. Calls to the plant were rerouted to Boston Scientific's Galway operating plant.

Boston Scientific, which employs 3,000 people at plants in Galway, Cork, Tullamore and Letterkenny, gave the copying operation the code name, "Project Independence".

The corporation said it felt forced to take such drastic action because Medinol had threatened to withhold supply of the stents.

However, when he summed up the case at the Federal District Court in Manhattan, Judge Hellerstein issued an 84-page ruling that strongly rejected any justification for the Dublin operation.

"Boston Scientific's argument is fallaciousbecause it cannot first contract with a party of known limitations and then complain of just those limitations. It is as if a man marries a poor woman, and then complains that she is not rich," he said.

He accused Boston Scientific of using an argument based on patent law that "proceeds tortuously" and one that is without merit.

The Dublin case was just one part of a larger $1 billion, or €743,000,000, claim by Medinol against Boston Scientific.

Judge Hellerstein struck out racketeering and other claims against two individual defendants in the case: Mr Peter M Nicholas, Boston Scientific's chairman and former chief executive and Mr Lawrence C Best, the company's chief financial officer.

The case is to return to the judge next January for a status conference and to assess if a settlement can be reached.