He also said he uses a "really good, steer ribeye steak" from Minnesota that is "marbled" better than most ribeye beef.
Marbling refers to the fat content in ribeye which, when grilled, makes it juicy and tender, Campo says. "You can taste the difference. It's almost like eating filet [mignon]."
Campo's attorney, J. Conor Corcoran, said the mark is necessary for Campo's to expand its business to cities in other states.
"It will help them franchise," Corcoran said. "If we want to be the sterling benchmark for the Philadelphia cheesesteak, we need that mark."
Campo's flagship is on Market Street near 2nd and it has satellite locations at Citizens Bank Park, Wells Fargo Center and Liacouras Center.
The complaint, first reported by Courthouse News, said Campo's was not trying to control "Philadelphia Cheesesteak," which Campo's says describes a "generic kind of sandwich."
In August, the trademark appeal board upheld a decision to refuse Campo's mark because it was "likely to cause confusion" with other marks and was mainly "geographically descriptive" of its sandwich.
The trademark office previously registered three trademarks to Philadelphia's Cheesesteak Co., Philadelphia Cheesesteak Co. and the Original Philadelphia Cheesesteak Co.
But Campo's contends those marks are different because they identify a "company" specializing in the wholesale distribution of sliced ribeye. Campo's mark, conversely, concerns the identification of a particular kind of sandwich, the complaint said.
Campo's said it's been using "Philadelphia's Cheesesteak" at its four locations and on its website since at least Jan. 1, 2009.
Contact Michael Hinkelman at email@example.com or 215-854-2656. Follow him on Twitter @MHinkelman.