What just happened? While numerous games now include a Battle Royale mode, the two biggest names in the genre remain PlayerUnknown’s Battlegrounds and Fortnite Battle Royale. But it seems the games' similarities might be a bit too close for comfort. PUBG Corp, the studio behind Battlegrounds, has reportedly filed a lawsuit against Epic Games for copyright violation.

According to the Korean Times, PUBG Corp filed the injunction in January. It asks the Seoul District Court to decide whether the similarities between Fortnite and PUBG constitute copyright infringement.

Following the release of Fortnite’s free-to-play Battle Royale mode in September, PUBG publisher Bluehole said it was concerned that Fortnite might be replicating the experience for which PUBG is known. The company later said it took issue over the fact PUBG is based on the Unreal Engine, and that developer Epic could prioritize its own game when it came to engine upgrades. Bluehole was also unhappy about Fortnite using the PUBG name in promo material.

"We just want to emphasize this is only a problem because Epic Games is the company that makes the engine we use and we pay a large amount of royalties to them. And we had this business relationship and we had trust that we would be getting continued support, and we were looking forward to working more closely with them to get technical support, maybe develop new features,” said a Bluehole rep last September.

Last month, PUBG Corp. filed a lawsuit against Chinese publisher NetEase in Northern California’s US District Court. It claimed that two of the company’s games, Rules of Survival and Knives Out, violate copyrights and trademarks held by PUBG.

No word on when the court proceedings will begin in Korea. "We filed the suit to protect our copyright," PUBG Corp. told the Korea Times. The move comes just as Epic gets ready to launch Fortnite in Cybercafes across the country.