A decade-long feud between Crocs and a competitor is heating up over the molded plastic shoes sold in Canada.

Crocs and Crocs Canada filed a statement of claim in Federal Court Nov. 1 against Double Diamond Distribution Ltd. of Saskatoon, which operates under the trade names Dawgs and Canada Dawgs.

The tussle continues a long battle between Crocs and USA Dawgs in the United States during which Crocs has alleged that Dawgs has infringed its patent. On the other hand, Dawgs has alleged false advertising, antitrust practices and corporate sabotage on the part of Crocs.

The Canadian lawsuit is aimed at a line of clogs with fleece liners that each company sells. Crocs maintains that the “Defendants’ ‘Fleece Dawgs’ products ..have applied the Crocs design and copy the Crocs…products.” The Defendants sell its shoes online and through the websites of Walmart and Home Hardware.

"We have asked the court in Canada to stop Dawgs' continuing infringement of Crocs' registered industrial designs, and compensate Crocs for its infringement,” Crocs said in a statement to CTVNews.ca.

“Any allegations made by Dawgs are a tactic to harass the company and its employees, and are without merit. Crocs is of the opinion that Dawgs has unlawfully profited from its imitation product for years without investing its own time, research, or money into making a product of their own.”

For its part, Double Diamond has teamed up with a Canadian law firm prolific in class-action lawsuits, alleging that Crocs’ shoes cost $2 to $4 to make but sell for $50, resulting in a windfall of profits for the Colorado-based Crocs It filed a statement of claim Oct. 27 in Saskatoon.

“This class action should interest every Canadian who has ever bought a pair of shoes,” said Tony Merchant of Merchant Law Firm.

“Relying on patent claims, Crocs’ Canadian sales in the last dozen years are estimated at an astounding $487,835,000. Huge profits are being earned,” Merchant said in a press release.

Merchant also alleges that Crocs has falsely promoted a patent on a material called Croslite.

“…Crocs has claimed Croslite as ‘patented’ even though Crocs and its executives are fully aware that it is not,” reads the press release.

“It will be reasonable for the Court to hold that the overprice paid by consumers is based on a belief that there is a patent and the product quality merits this high premium pricing.”

Merchant Law Group is well known for taking on class-action cases, including those against residential schools and the 60s Scoop, retailers, auto companies, cellphone providers, medical device manufacturers and pharmaceutical makers.

None of the respective allegations have been proven in court.

The clunky, colourful Crocs have become the subject of widespread satire and mockery ¬– Time magazine in 2010 called them one of the world’s “50 Worst Inventions” - but they are also fiercely defended by those who call them supremely comfortable.

Crocs, incorporated in 2002, has sold more than 300 million pairs of shoes in more than 90 countries.