https://www.gamespot.com/articles/pubg-dev-sues-fortnite-studio-for-copyright-infrin/1100-6459244/

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."