According to the U.S. Patent and Trademark Office, Brooklyn-based artist Paul Ingrisano was granted a registered trademark on the 3,000 year old mathematical constant (and sixteenth letter of the Greek alphabet) near the end of January.
He had originally filed for a trademark on the Pi symbol in November of 2012 on the grounds that his company "Pi Productions Corp" produced t-shirts featuring the symbol, followed by a period.
Wired reports that when Ingrisano discovered a wide array of apparel containing the Pi symbol on Zazzle.com, a massive online retailer that allows users to create their own merchandise, he contacted his lawyer.
"It has been brought to our client's attention that your business, Zazzle Com/AKA Zazzle Inc., has been using the mathematical symbol 'pi,' referred to herein as the 'PI trademark,' in association with the marketing or sale of your products or of products offered through your services," wrote Ingrisano's lawyer, Ronald Millet, in a cease-and-desist letter sent to the company on May 16.
"We have evidence of your unlawful products to preserve as evidence. Accordingly, you are hereby directed to CEASE AND DESIST ALL COPYRIGHT INFRINGEMENT," the letter continued, citing U.S. registered trademark number 4473631.
Zazzle responded by immediately removing all garments including any form of the symbol, which is popular among math geeks and often used as fodder for jokes.
"This impacted thousands of products," said Zazzle spokeswoman Diana Adair to Wired. "How many actually sold would be a much smaller number of course."
Zazzle sent a formal notice to its sellers informing them of the ban and removal, but many were unimpressed with the news.
Outraged by the idea that someone had trademarked a mathematical symbol, Lartigue, like many around the web, argued that the U.S Patent office had made a mistake.
"Pi is an irrational constant in mathematics. It's the name given to the ratio of a circle's diameter to its circumference. It's denoted by the Greek letter 'pi'. This symbol is used in every mathematical text and paper involving this ratio, and has been since at least 1706," he wrote "And now someone's claiming they've trademarked it and no one else can use it? That's like trademarking the number three, or hell, the e in the design, which is another mathematical concept. It's clearly absurd to anyone except, I guess, Zazzle."
Jez Kemp, another blogger and Zazzle seller who has several Pi designs for sale, argued similarly on his blog that "this would be like McDonalds claiming the letter M as a trademark. The trademark is in the combination of style and symbol, not the symbol itself."
Both bloggers responded to Zazzle, informing the company that Ingrisano's trademark specifically protects the Pi symbol with a period after it -- something neither of their designs included.
In a reply to Kemp, published on an active Zazzle forum called "Mathematical 'Pi' symbol is trademarked?" Zazzle's content management team defended its ban.
"You are correct in the description of the registered trademark as having a period," wrote Zazzle. "However, representatives of PI Productions Corp. is exercising their rights to protect their mark by not only restricting the use of their trademark, but also any similar marks that is likely to result in consumer confusion as part of the Lanham Act."
Similar replies were sent to other Zazzle users, resulting in an outpouring of rage and frustration online.
After much outcry, Zazzle decided to restore all products that had been removed for making use of Pi on Friday.
"After reviewing the take-down request more closely, Zazzle has decided to restore 'Pi' products as of today," wrote the company in a Zazzle forum. "Zazzle is a marketplace for a community of artists, and we want to continue to support artists who are creating original artwork."
By Monday, 5,338 different products were being returned under the search term "Pi" on Zazzle.
Custom Pi 3.14 Math Geek Tie from Zazzle.com24 Hour Shipping on most orders. Custom Pi 3.14 Math Geek Tie created by bellamandu. Customize this design with your own text and pictures or order as shown.
While many were pleased by Zazzle's decision to ignore the cease and desist letter from Ingrisano's lawyer, the design community is now keeping a close eye on the artist.
Several Zazzle forum users have made note of the fact that Ingrisano also has a pending trademark registration for the use of "I<3" -- which means "I love" in netspeak.
"OH MY GOD! From the same guy????" wrote a user named ArtsmakersWorlds. "Is he going to register every number and symbol possible?"
In a lengthy post about the I<3 filing, Ben Davis summed up what much of the web was feeling on artnet news, writing "The Internet definitely does not <3 Paul Ingrisano right now."
What are your thoughts on trademarking symbols? Should the U.S. Patent Office be less lenient in the trademarks it registers, or is all fair in love and design? Weigh in below.