Dive Brief:

• Frankie's on the Park, a Chicago-based tween apparel retailer, on Friday sued Francesca's in the U.S. District Court for the Northern District Of Illinois. Frankie's is asking the court to stop Francesca's use of "Franki" and to award legal fees and damages.

• Frankie's is alleging "trademark infringement, unfair competition and false designation of origin and unfair and deceptive trade practices," related to Francesca's tween brand, Franki, per court documents. Frankie's on the Park runs two stores, in Chicago and Santa Monica, California, its e-commerce site, and pop-ups in various cities.

• Francesca's — which earlier this month spun Franki into a stand-alone brand after a quiet launch before its bankruptcy last year — didn't immediately return requests for comment. Frankie's on the Park said in its suit that it informed Francesca's of its trademark after learning of the news, which was covered by Retail Dive and other outlets.

Dive Insight:

Frankie's says that Francesca's name for its sub-brand is troublesome because the two players are in the same market segment — apparel for tween girls. In its lawsuit, Frankie's points out that it was there first.

"Frankie's established its retail store in 2008, more than 13 years ago," the retailer points out in its lawsuit, where it also details its various names and nicknames. "Frankie's has established a valuable niche in the $33 billion girls tween clothing market and become synonymous with high quality tween fashion and lifestyle."

The situation creates both "forward confusion" and "reverse confusion," according to Bart Lazar, an attorney for Frankie's. Forward confusion is when consumers familiar with Frankie's think the two are related or identical, while reverse confusion occurs when a large newcomer like Franki, backed by Francesca's, creates the first impression with potential Frankie's customers.

"Those consumers are going to believe that Frankie's is the copycat," Lazar said by phone.

The Chicago-based company also notes similarities between the two brands' typefaces. "Frankie's and Franki are marks which are virtually identical in sound, look and appearance — simply too close to co-exist in the exact same market targeting to tweens," the company said in its filing.

While Frankie's on the Park is what is registered as a trademark, the retailer has a good chance of persuading the court that "Franki" and "Frankie's" could be mixed up — and not just because they operate in the same narrow segment, or have the same sound and similar look, according to Alan Behr, fashion industry attorney and partner at Phillips Nizer.

"One, the closer the unity of products, stronger the case," Behr said by phone. "But, two, you've chosen your market as being kids. The question isn't whether a supplier, like a factory in China, would be confused. The question is, will a 10-year-old girl be confused?"

Moreover, while there may have been a time when a smaller retailer with just two stores wouldn't have reached the same markets as a national retailer, e-commerce changes that, Behr said. Lazar also noted that, as of Monday, Frankie's has thousands more Instagram followers than Franki.

"They're just starting out," Lazar said. "If you do your own Google search, you'll see that consumers, whether adults or tweens, are going to be confused. They're going to be faced with both right now, in the middle of the holiday season."

A lawyer would typically caution against using such a similar mark, according to Behr.

"Having gone ahead, they've now taken the risk, and now it comes down to these interesting questions of — to what extent would this market be confused simply because in one case 'Frankie's on the Park" and another 'Franki' both use the term as their lead, core, recognizable symbol," he said. "I think that even though the registration is not congruent, there is a compelling case that kids will be confused."