After suggesting it might take action, the developer of PUBG has filed a lawsuit against the creator of Fortnite on the ground of copyright infringement. PUBG Corp., which is based in Korea, filed its lawsuit against US-based Epic Games with the aim of getting the courts to decide if Fortnite represents some kind of copy of PUBG. A PUBG Corp. representative told Korea Times that its lawsuit against Epic was actually filed back in January in the Seoul Central District Court. Epic Games Korea, a division of Epic Games, is the defendant.

Back in September, PUBG Corp. said it was "concerned that Fortnite may be replicating the experience for which PUBG is known." The Korean studio said PUBG is the "first standalone Battle Royale survival shooter game."

The report does not mention any specific claims in lawsuit, but PUBG Corp. said previously that it had "concerns" about Fortnite's UI, gameplay, and "structural replication" as it relates to the similarities between the gameplay and systems in both PUBG and Fortnite.

Adding to the drama, PUBG Corp. apparently had a business relationship with Epic, as the Korea studio licensed Epic's Unreal Engine for PUBG.

In March, PUBG creator Brendan Greene--the Playerunknown from the game's title--said Fortnite is good for the battle royale genre overall. "It's great that the battle royale space is expanding and Fortnite is getting battle royale game mode in the hands of a lot more people," he said, as reported by The Verge.

This time last year, PUBG was seen as the No. 1 battle royale game, but a lot of attention and awareness currently is around Fortnite. Epic's game has exploded in popularity, and is reportedly a money-making juggernaut. A recent report said the free game brought in almost $300 million in revenue during April alone from its various microtransactions.

PUBG Corp.'s lawsuit against Epic is apparently limited to Korea. We searched the United States courts database and found no results for a lawsuit against Epic from PUBG Corp. That being said, whatever happens in the Korean lawsuit could impact other parts of the world. This will be an ongoing story, so keep checking back for more.

An Epic Games representative told GameSpot, "We don't comment on ongoing litigation."