Photo: Benjamin Haas /
3 June 2014Trademarks

‘Pi’ trademark causes stir with online retailer

A US online retailer has resisted calls for “thousands” of clothes featuring the mathematical sign ‘pi’ to be taken down after an artist claimed he owns a trademark for the symbol.

Paul Ingrisano demanded that Zazzle, which lets users create their own designs, remove its infringing merchandise in  a cease-and-desist letter sent to the company in May.

Despite initially complying with Ingrisano’s order, Zazzle has since begun  offering the merchandise again.

The trademark at issue is US number 4,473,631, which was issued to Ingrisano and his company Pi Productions Corp in January this year.

The image features the symbol ‘π.’ followed by a full stop. According to the US Patent and Trademark Office website, it is registered under classes covering athletic apparel, including shirts, pants, jackets, footwear, hats and athletic uniforms.

After noticing the Zazzle products last month, Ingrisano’s lawyers issued a cease-and-desist letter to the company

“It has been brought to our client’s attention that your business … has been using the mathematical symbol ‘pi,’ referred to herein as the ‘PI trademark,’," the letter said.

"We have evidence of your unlawful products to preserve as evidence. Accordingly, you are hereby directed to cease and desist all copyright infringement," it continued.

It added: “It is important that Ingrisano exercises his right to protect his trademark. It serves as an important and distinctive representation of the origin of his products.”

Zazzle sent a notice to its users informing them of the ban but, after facing criticism from some of them, decided to restore all the removed products on May 31.

"After reviewing the take-down request more closely, Zazzle has decided to restore 'Pi' products as of today," the company said in a statement.

It added: "Zazzle is a marketplace for a community of artists, and we want to continue to support artists who are creating original artwork."

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