A Twickenham props designer who fought against the force of blockbuster filmmaker George Lucas has won a partial victory in his court battle.

The battle between Andrew Ainsworth, owner of Shepperton Design Studios on Twickenham Green, and Mr Lucas' company Lucasfilm had been continuing for years, spanning continents as different courtrooms heard the allegation that the props designer illegally reproduced and sold stormtrooper helmets and armour he had made for the original 1977 Star Wars film.

At 2pm at the Royal Courts of Justice today, Justice Mann dismissed Lucasfilm claims of infringement of English copyright, passing off, breach of confidence and breach of contract.

In 2006 an American court found Mr Ainsworth guilty of copyright infringement, unfair competition and trademark infringement and awarded Lucasfilm $20m (£10.1m) in damages.

Due to Mr Ainsworth's British residency and inability to pay the colossal sum, the court order had to be enforced by the British High Court but Justice Mann said the court would not enforce the US judgement.

Lucasfilms succeeded only in persuading the judge that minor sales to the US were in breach of the US but not English copyright law. Mr Ainsworth admitted sales into America were between £25,000 to £30,000.

This year the costume maker launched a counter suit against the US company for a share of its £6billion merchandising profits since the 1977 film but this was also dismissed by the judge.

Justice Mann, who had retired at the start of May to consider his judgment, said that Lucasfilm had adopted a "sledge hammer or steamroller approach".

He went on to say: "What is quite clear is that Lucas is determined to stop Mr Ainsworth by whatever legitimate legal means are open to it, including the threat of a £10m judgement hanging over him.

"Whether or not it is entitled to do that is of course a matter for this court."