Salt Lake Comic Con opens September 24. Held for the first time in 2013, the rapidly growing event drew 120,000 in 2014 and this year will fill the entire Salt Palace Convention Center in Salt Lake City.

Salt Lake Comic Con is not only distinguished by its explosive success. Among all the Comic Cons in America, the event run by Dan Farr Productions is the only one being sued by the San Diego Comic Con (SDCC) for trademark infringement.

SDCC alleges that the name of Salt Lake City’s event is too similar. In court papers filed in August 2014, SDCC claimed that SLCC had piggybacked on its “creativity, ingenuity, and hard work,” and by using the Comic Con name “intended to suggest, mislead and confuse consumers into believing that the Salt Lake Comic Con convention is associated with, authorized by, endorsed by or sponsored by SDCC.”

Comic-Con International, the organizers of San Diego Comic-Con and WonderCon, own the trademarks on San Diego Comic-Con, Anaheim Comic-Con, San Francisco Comic-Con and Los Angeles Comic-Con.

Although the U.S. Patent and Trademark Office (USPTO) registered the Salt Lake Comic Con trademark in July, the ultimate fate of the trademark depends on a settlement of the suit or a court decision.

In August, U.S. Magistrate Judge Jan Alder gave both conventions until August 18, 2016 to settle, and set a timeline for discovery and other actions that could lead to a trial in late 2016 or early 2017.

One head-scratching oddity about the suit is that SDCC did not originate the “comic con” nomenclature. It was first used by the New York ComiCon in 1965.

Andrew Porter recalls, “In 1965, I ran off the program for a New York ComiCon — note abbreviation, not what’s used now — on my spirit duplicator, all 125 copies. And I worked on several ComiCons, including one with Ted White, John Benson, Mike McInerney and others, in the mid-1960s. And now someone wants to [trademark] the name?”

Salt Lake Comic Con management is well aware of the history, and displays online a huge array of documents supporting their position. They emphasize that more than 90 other events have been called “Comic Cons.” Several are megacons. Denver’s drew a reported 101,500 attendees in May. A Seattle convention had 80,000 in March. The New York Comic Con says it attracted 151,000 last year.

And it actually was not until 2007 that the nonprofit behind SDCC trademarked the Comic-Con name which it has been using since 1970.

Peter Hahn, a lawyer who represents the nonprofit on trademark issues, pointed out that registration is not required to protect a mark. Mr. Hahn said the nonprofit’s tools in dealing with more than a dozen conventions that have used some form of the Comic-Con name have included warning letters and licensing arrangements. Litigation has been used for “the most egregious” cases, he said.

Last August, the San Diego group filed an infringement suit against the operators of Salt Lake Comic Con, who, according to the complaint, had gone so far as to wrap an Audi with advertisements for their convention and drive it around San Diego. The Salt Lake operators countersued, asking the United States District Court for the Southern District of California to declare the San Diego nonprofit’s trademark claims invalid.

Encouraged by the USPTO’s initial decision granting registration to the Salt Lake group, a large number of other local comic cons have now launched trademark bids .