Weeks after forcing the shutdown of a popular, fan-run "pirate" server that ran a classic version of, Blizzard now says it basically had no choice but to go after Nostalrius to protect its legal rights.

"Why not just let Nostalrius continue the way it was? The honest answer is, failure to protect against intellectual property infringement would damage Blizzard’s rights," World of Warcraft Executive Producer and Vice President J. Allen Brack writes in a post on the official WoW forums. "This applies to anything that uses WoW’s IP, including unofficial servers. And while we’ve looked into the possibility—there is not a clear legal path to protect Blizzard’s IP and grant an operating license to a pirate server."

In the narrowest sense, Blizzard's copyright wouldn't suddenly be invalidated if the company decided to look the other way for one popular "vanilla" server; you can't lose a copyright just by failing to defend it legally. Still, failure to go after Nostalrius would have done some damage to the idea that Blizzard is in full control of the World of Warcraft IP and could have encouraged others to think that such unofficial servers were OK. Even now, there are plenty of other pirate servers out there running previous, current, and/or modified versions of World of Warcraft, most of which have yet to draw Blizzard's legal fire.

In his post, Brack goes on to say that Blizzard has looked into running a Nostalrius-style "classic" server on its own, but that "none could be executed without great difficulty. If we could push a button and all of this would be created, we would. However, there are tremendous operational challenges to integrating classic servers, not to mention the ongoing support of multiple live versions for every aspect of WoW."

This might seem a little hard to swallow, seeing as a group of volunteers managed to support hundreds of thousands of active users on Nostalrius for years without the resources and experienced staff available to Blizzard. At the same time, any Blizzard-run classic server would likely need to meet a higher bar for scalability and stability, given an expected higher visibility and player count.

And remember, Blizzard said official classic servers would be "challenging" and "difficult" to do, not impossible. Reading between the lines, it seems Blizzard may have crunched the numbers and figured spending the time and money to set up classic servers for a niche audience just wouldn't be good for the bottom line (even if it would be popular with a segment of the player base).

As a compromise, Brack says Blizzard is considering opening up a "pristine" realm that turns off newer features like leveling acceleration, character transfers, heirloom gear, character boosts, Recruit-A-Friend bonuses, and more. "We aren’t sure whether this version of a clean slate is something that would appeal to the community, and it’s still an open topic of discussion," he said.

Brack also added that Blizzard has been in active discussions with the team behind Nostalrius and will continue to talk with them going forward. We'd be very interested to hear what those discussions entail, because today's statement makes it pretty clear that Blizzard isn't all that interested in allowing Nostalrius to come back—or in replacing it with something similar.