A Yorkshire HIV charity has been threatened with legal action over the name it uses for its free condoms.
Sexual health group Yorkshire Mesmac issues condoms to gay and bisexual men under a scheme called Confi'doms.
But Britannia Medicare, which makes condoms under the Confident brand, has ordered the charity to sign away its name by Monday or end up in court.
Yorkshire Mesmac has refused to comply and accused the company of a "shocking" attempt to bully a small charity.
The charity says it can prove it was using the Confi'dom name in late 2001, before Middlesex-based Britannia registered the Confident name in May 2002.
It also dismissed the claim that people would confuse the two names as "ridiculous" and said it had been advised by lawyers to stand its ground.
Leading trademark lawyer Lindsey Wrenn, based at the Leeds offices of solicitors Pinsent Masons, has offered her services free of charge to the charity.
Yorkshire Mesmac director Tom Doyle said: "The tone of the letters sent to us by Britannia's solicitors is aggressive and threatening - we feel that they are trying to bully us.
"I think they are banking on us lying down and meekly accepting what they want, but we simply won't."
He said the legal wrangle was a waste of the charity's limited resources and had distracted him from important sexual health work in the region.
The organisation has offices in Leeds, Bradford, Huddersfield, Hull, Scarborough, Sheffield, Wakefield and York.
Nobody at Britannia Medicare was available for comment on Friday.