Every year on March 14th, teachers, scientists, and those who just love math and numbers celebrate Pi Day, a special day that pays tribute to Pi… otherwise known as the number 3.14 (plus a bunch ...

In January, the U.S. Patent and Trademark Office gave Ingrisano a trademark on the symbol π.—pi followed by a period—a design Ingrisano uses on T-shirts sold at some brick-and-mortar stores.