An animal rights activist is vowing to fight a major pork manufacturer over the ownership of a website that criticises the company over factory farming.

Campaigner Mark Eden has been threatened with legal action by Premiere Bacon Company over his use of the domain name premierbacon.co.nz.

The official Premiere Bacon Company website is premierebacon.co.nz, although the website uses both "premier" and "premiere" in referring to the company.

Mr Eden said Wellington Animal Rights Network bought the domain name three weeks ago for $25 and set up the site as part of a campaign against Premiere Bacon.

Activists this month chained themselves to the bumper of a Premiere Bacon delivery truck in downtown Wellington.

A lawyer for Premiere Bacon demanded Mr Eden deregister the name or hand it over to the company by 5pm last Friday.

Solicitor Ann Hall wrote to Mr Eden last week saying he had no right to register the name.

"Your misleading and deceptive behaviour in doing so, exacerbated by you permitting the Wellington Animal Rights Network to use the domain, is in breach of the law."

Ann Hall said the company would commence proceedings if he did not give up the name.

Mr Eden said he had ignored the deadline and was expecting to hear from the lawyer today.

He had not taken legal advice but after researching domain name disputes believed he had the right to use the website for "fair criticism".

"It looks like I'm going to be OK but Premiere Bacon has high-powered lawyers ... who seem to be trying to get it off me however they can."

The website says photos of pigs on the site were taken on Premiere's main Carterton farm, and says "all other pork producers keep pigs in equally appalling conditions and are just as guilty of animal cruelty". Mr Eden claims the company "hassled" the domain host over copyright of company logos and the website was taken down for a few days to be redesigned.

"Their lawyers looked at it and said copyright was the only issue they were worried about."

Mr Eden said he would not back down over the legal threat.

"I do not like bullies and I do not like animal abuse, so I'm certainly not going to hand over ownership of the domain name without a fight."

He said Premiere was responsible for the deaths of tens of thousands of pigs every year, and "it's an issue we are going to continue to highlight as much as we can".

Mr Eden said the Pork Industry Board had since registered several domain names relating to the industry.