The NetApp-Sun Patent Litigation Is On: Anyone Know of Any Prior Art?

When Network Appliance first announced it had filed a lawsuit against Sun Microsystems early in September over alleged patent infringement in ZFS, I didn't know what to make of it.

The public arguing back and forth didn't mean much to me. Even the Sun email [PDF] to NetApp the latter made public to bolster its side of the argument could be interpreted more than one way, and it was also clearly the middle of a conversation, with no way to know for certain what had happened before the email. It began, after all, "We are in receipt of your October 23, 2006 letter..." Personally, I think it's bad form to reveal private communications, but if you do, cherry picking one out of several isn't convincing to me, and anyway I like to reach conclusions based on what I see officially filed in courts. Compare what SCO told the media ("a mountain of infringing code") and what it told Judge Dale Kimball in a courthouse in Utah years later (in essence: "no code, but if you let us spring a surprise on IBM after discovery is closed, we can find maybe some methods and concepts to hit them with").