Grand Theft Auto V is well-known for its numerous, player-created mods and brilliant machinima videos , so it comes as a surprise to learn that one of the game’s most popular modding tools, OpenIV, has been taken offline. Its developer claims the reason behind the shuttering is a cease and desist letter from GTA publisher Take-Two Interactive.

OpenIV lead developer ‘GooD-NTS’ revealed the news on gtaforums.com . They write that despite taking precautions such as not “messing with Online” and “no distribution of original data and code,” take-two's C&D notice claims OpenIV “allow[s] third parties to defeat security features of its software and modify that software in violation Take-Two’s rights.”

OpenIV, which was first released in 2008, is a multi-purpose editor and archive manager for GTA IV, GTA V, GTA: Episodes from Liberty City, and Max Payne 3. It’s incredibly popular among modding fans, and the shuttering has been met with a lot of anger.

The OpenIV team says that while they could fight the decision in court, the time this would take means a legal battle just isn’t worth it.

"Going to court will take at least few months of our time and huge amount of efforts, and, at best, we'll get absolutely nothing," the post says. "Spending time just to restore status quo is really unproductive, and all the money in the world can't compensate the loss of time."

One unusual aspect of the whole situation is that GooD-NTS says Take-Two’s letter is "illiterate both technically and grammatically." That certainly seems odd, especially given the size of the company behind it.

OpenIV is no longer available to download and won’t be receiving any more updates. Take-Two and developer Rockstar, which has publicly supported mods in the past, have yet to comment on the matter.