On January the 9th NCSoft filed a lawsuit against En Masse Entertainmet seeking an injunction against the launch of the upcoming MMORPG TERA, scheduled for release in the US on May the 1st and and in Europe on May the 3rd.

NC Soft alleges that "based on what is now publicly available information regarding TERA, coupled with an analysis of the already-released Korean version of the game, it is evident that the US Version of TERA incorporates NCSoft's trade secrets as well as NCSoft's copyrighted work" as you can read in the official court document."

En Masse's vice president of publishing Chris Lee (formerly Senior Director at NCSoft) posted on the TERA official forums (now temporarily unavailable due to the launch of the new website) responding to the lawsuit and reassuring the game's fans:

We are disappointed that NCsoft is attempting to mar the launch of Tera. Unfortunately we can't discuss much publicly due to the sensitivity of legal actions, but we do outright reject the NCsoft claims, and we are going to do everything in our power to defend and protect ourselves.

To all our supporters who have been anticipating the arrival of TERA - please know that this situation has no impact on our continuing efforts to realize the vision we have for our game. We are committed to making TERA awesome and delivering the game to you on time on May 1. Thank you for your patience and support.

The issue follows a similar lawsuit in Korea, that created a quite complicated situation. Former NCSoft employees that founded Bluehole Studio (the original developer of TERA) were accused of stealing trade secrets and copyrighted development material of Lineage 3, using them to create TERA. 

A number of the former developers were criminally convicted and an injunction against the use of the assets in TERA was ruled. This, though, didn't stop the release of the game. On the other hand damages initially awarded to NCSoft were reversed by the intermediate appellate court.

At the moment both the convictions and the overruled monetary damages are awaiting final judgement by the Supreme Court of South Korea.