One is a Pulitzer-prize winning national newspaper and website. The other is a free digital magazine covering the world of martial arts

But lawyers employed by The Guardian have written to magazine Martial Arts Guardian warning that it is “inevitable consumers will be confused” between the two.

The trouble began for Martial Arts Guardian when it applied to register its name as a trademark.

The title was launched by four friends five months ago as a “labour of love” and has been growing in popularity so they wanted to protect the brand.

They were surprised to receive a letter from City lawyers Olswang warning them that Guardian News and Media was opposing their application.

In the letter, the law firm said that “renowned daily newspaper” The Guardian was founded in 1891 as the Manchester Guardian (actually it was founded in 1821) and has been known as The Guardian since 1959.

It said: “As is apparent from our client’s registered trademarks and use of its brands, they have established a recognised and distinctive family of Guardian marks in respect of, amongst other things, publishing services.

“Our client’s attention has recently been drawn to the UK trademark application detailed above and filed in your name. The application is for a mark similar to The Guardian and covers services that directly conflict with GNM’s Rights…

“In view of this, and our client’s substantial reputation in the field of publishing, it is inevitable that consumers will be confused as to the original of any publishing services offered under a Guardian brand. Our client is therefore minded to oppose your application.

“However, in order to avoid the costs associated with opposition proceedings we have been instructed to advice you to withdraw you trademark application.”

The letter was dated 6 July and gave the Martial Arts Guardian ten days within which to comply.

Co-founder of the Martial Arts Guardian Simon Keegan is surprised by the move.

He said: “The format of the mag is about as different from The Guardian as you can imagine. It’s an A4 martial arts magazine, it’s not a blue mastheaded newspaper or anything like that.

“It definitely wasn’t our intention to be confused with The Guardian because it’s a completely different readership. We don’t have recipes in it for falafel or anything like that.

“It seems quite unfair because there are other publications that have the word Guardian that are more like The Guardian. The Chorley Guardian and Middleton Guardian are newspapers at least for instance. It seems like a bullying tactic.”

Press Gazette has counted at least 50 news publications in the UK which include the word Guardian in the title, including: the Farmers Guardian, Crewe Guardian, South Wales Guardian and Cornish Guardian.

The Martial Arts Guardian is now approaching its fifth monthly issue and aims to fill a gap in the market.

Keegan said: “We felt the existing martial arts publications tend to feature the same old faces of people who had a bit of money to spend with them. We just focus on people who are good practictioners of martial arts who may be unsung heros.”

It is run by Keegan, a Manchester-based Karate instructor, Russ Jarmesty, a Jujutsu instructor living near Wigan, and Scott Caldwell, a Krav Maga instructor from the Isle of Man.

Together they are referred to as the "Martial Arts Guardians". A fourth 'Guardian', Steve Rowe, who the legal letter is addressed to, is no longer involved.

They are now considering their options and look likely to withdraw the trademark application and may even have to change the name of their magazine.

A Guardian News & Media spokesperson said: "We can confirm that solicitors acting on our behalf contacted the organisation in question to invite them to withdraw a trademark application as it overlapped an earlier registered trademark owned by Guardian News & Media Limited. The organisation confirmed they would withdraw their application as they do not use the name and have no further interest in the application. They are welcome to discuss this further with us should they wish."