A Victoria, B.C., artist who trademarked her name is fighting one of the world's largest toy companies, after Mattel's American Girl tried to take the name for one of its new dolls.

American Girl is a wholly owned subsidiary of Mattel Inc.and is headquartered in Middleton, Wis. American Girl announced its expansion into Canada last October.

Mattel's American Girl Caroline Abbott doll depicts an American girl from 1812 who helps in the war effort against the Canada-based British forces. (Americangirl.com)

Mattel wants to register "Caroline" as a trademark in Canada to be used for its Caroline Abbott doll, a new entry in the American Girl line of historical characters by Mattel.

But the Canadian Intellectual Property Office is blocking the request, saying Mattel's intended use of the trademark "Caroline" would be too similar to the trademark for "Carollyne" that it issued in 2008 to Victoria's Carollyne Yardley.

Yardley's trademark covers the use of her name for her artwork, which includes paintings, books, caricatures, toys and dolls — many of which currently fall into her series of Squirrealisms, which tend to feature human figures depicted with squirrel heads.

Victoria, B.C.'s Carollyne Yardley coined the term "Squirrealism" to describe her signature style of artwork using squirrel faces in paintings, photographs and digital art, which she brands in Canada under her trademark "Carollyne." (Carollyne.com)

Yardley says she has spent thousands of dollars already fighting American Girl's application to cancel her trademark, and now wants to warn other artists and entrepreneurs about the expenses of Canada's trademark process.

Under the current system, a clause kicks in three years after a trademark is registered that allows anyone to challenge it. It's part of an effort to remove dead wood from the registry.

With American Girl applying for a competing mark, Yardley has to prove she is using her trademark.

"This is costly, so you need to have a contingency fund, anywhere beginning from $3,000 to $5,000," Yardley told CBC News.

Yardley says she has spent even more than that after negotiations to share the trademark with the American Girl doll and book line fell through. She also expects it will cost even more to keep fighting if she wins her current dispute and American Girl proceeds with an appeal to a higher court.

Trademark lawyers will explain there is a potentially great financial benefit to having a trademark and the exclusive rights that come with it, so it makes sense to put an onus on the trademark owner to police and defend its use. Many are even opposing a proposed change to Canada's trademark legislation that would allow people to register without proving they use the mark for anything.

Yardley, photographed for Focus Magazine in 2013, says she thinks other artists and entrepreneurs may not be aware of the costs involved in defending a trademark. (Tony Bounsall/Carollyne.com)

Yardley says she see the benefits of the trademark system and understands that American Girl was just following a process when it challenged her mark.

But she also questions how much other artists and small business owners know about how much it costs to defend their trademarks.

Representatives with American Girl told CBC News they don't comment on ongoing legal issues, but said the company is excited to be opening its first two Canadian stores this weekend, in Vancouver and Toronto.

American Girl, a wholly owned subsidiary of Mattel, started 25 years ago as a line of dolls and books depicting preteen girls in historical times. The dolls alone cost around $120 US each.

The line has since expanded to include sets of matching accessories and a line of contemporary dolls.

Last year, Mattel reported its American Girl division had $100 million in sales in the first quarter alone. That figure takes into account sales of dolls, accessories and even doll hairstyling at stores in New York, Los Angeles, and at the line's flagship store in Chicago.