icatch9 - the criterion collection is a continuing series of important classic and contemporary films, dedicated to gathering the greatest films from around the world and publishing them in editions that offer the highest technical quality and award-winning, original supplements.
you can check out their website
basically, they buy the rights to print a movie with their special features for a while, and then, as is the case with SOTL, they give up the rights. the criterion SOTL is no longer in print, as there was a new special edition of SOTL, so the criterion is sought after as a collectible and as a great dvd...
i'm still waiting for them to get the rights back for the adventures of baron munchausen... they only put that out on criterion laser disc!