The New Zealand Rugby Union has been red-carded in its bid to trademark the silver fern for exclusive use in All Blacks merchandise.

In an intellectual property rights row that has dragged on for four years, the NZRFU wanted to trademark "a black rugby jersey, or casual shirt made in the style of a rugby jersey, bearing a fern and with a white collar".

Union deputy chief executive Steve Tew said the bid was aimed at one "constant area of misunderstanding".

"We know people that buy jerseys are mistaken into thinking they're buying a genuine article when they're not, and off a company that don't have the intellectual property rights to the genuine article, and who are not returning the benefit from the purchase back into the game, which is what we do."

But 12 clothing manufacturers around the country joined forces to argue that the fern belongs to all New Zealanders and should not be restricted to the union and the All Blacks.

Jennie Walden, assistant commissioner of trademarks, agreed and in her judgment released yesterday said the fern was "very broad in scope and had a low level of inherent distinctiveness".

"Accordingly, the mark is not registrable," she ruled in a written decision.

The NZRFU registered a trademark on the words "All Blacks" and on its own stylised silver fern in 1991.

A key argument in this application was whether any fern and black jersey were a symbol of the All Blacks.

The Intellectual Property Office accepted that the opponents - who mainly manufacture jerseys for the tourist trade - had made significant sales of rugby jerseys in the style the union was seeking to protect both before and after the application date in June 2001.

Auckland barrister Alex McDonald, who represented the opponents, said an important aspect of the decision involved a recognition that the motives of the manufacturers were not "questionable".

"Quite the reverse, in fact, as the Intellectual Property Office asked why, if the Rugby Union considered that the opponents had acted improperly, it had not taken steps against those traders for breach of the Fair Trading Act," she said.

Neil Crawford, managing director of Crawford Souvenirs, one of the opponents, said the trademark application "forced us to act to defend a national symbol on a black jersey for future generations, and not be ring-fenced for the commercial benefit of one organisation".

Terry Wilson, company director of Seabreeze Fashions, another of the opponents, said the Rugby Union was entitled to use its own-style fern and the word "All Blacks".

"But the fern belongs to all of us so I thought it was a pretty rude application," he said. "It's a victory for common sense."

Mr Wilson said his company would have suffered job losses if it was no longer allowed to sell silver fern-tagged garments to tourists.

Mr Tew said last night he was disappointed with the ruling.

"Frankly we find some of the trading offers done around our intellectual property to be rude and against common sense.

"We'll continue to watch very closely and ensure the rights we already have in place are not infringed. And if they are, we will act."

- Additional reporting Derek Cheng