Running club 3RUN2's T-shirt slogan (left) was trademarked. Fleet Feet came out with a shirt with a similar logo (right). View Full Caption Courtesy/3RUN2; Twitter

OLD TOWN — The brother-and-sister team behind a Chicago running club is considering legal action against running store Fleet Feet for using a version of their T-shirt slogan.

The club, 3RUN2, started more than three years ago as a way to organize free group runs on a weekly basis. You can spot the group by their shirts, which say "Chicago Is For Runners," a slogan club founders Micaela and Nico Bernal said they thought up and trademarked.

Someone in the 3RUN2 community alerted the pair Thursday that Fleet Feet, which runs seven locations throughout the Chicago area, was selling a shirt with a similar slogan, which Nico Bernal called "unsurprising."

"When you put some cool stuff out into the world you have to expect that people are going to copy you or be inspired by you," Nico Bernal said. "We're trying to provide something that's fun and authentic. To see something out there that's so similar that's not associated with us is disheartening."

The Fleet Feet T-shirt reads, "Windy City Is For Runners."

But Robin Monsky, spokeswoman for Fleet Feet, said the slogan is far too common to be considered original, pointing to the famous tourism slogan "Virginia Is For Lovers" as the origin.

According to Monsky, Fleet Feet began selling the T-shirts in February, which is before 3RUN2 registered for the trademark, according to trademark records shared with DNAinfo Chicago.

Still, Fleet Feet would be willing to take the T-shirts off the shelves if there is an issue going forward because the company was completely unaware that the slogan had been trademarked, Monsky said.

"Fleet Feet is not looking to infringe upon anyone in any shape or form," Monsky said. "All they want to do is lift up the running community and celebrate the running community."

Yet Michaela Bernal believes a large company is profiting off a small, independently-run club.

"We're a very do-it-yourself, independent community and then you come and see this bigger company take your idea," Micaela Bernal said. "They're making a profit off of our culture."

Now she and her brother are considering legal action against the running store.

"We put a lot of time and effort into coming up with this merchandise," Nico Bernal said. "We have to protect our intellectual property."

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