Christopher Renzi filed the lawsuit on Monday in federal court in Rhode Island against the Real Madrid forward and a Danish company, JBS Textile Group. The company sells underwear with the phrase "CR7," a combination of Ronaldo's initials and jersey number.
Renzi says he uses the trademark granted in 2009 on clothing and that he's also used it for a seven-minute exercise programme. He says in his lawsuit that "CR7" is a combination of his own initials and the day he was born, October 7.
JBS Textile sells CR7 underwear, socks and other items in Europe and hopes to start selling in the US soon. Its lawyer would not comment.