Blizzard Entertainment, maker of the popular computer games
Diablo, WarCraft, and StarCraft, won its case in the Eastern District of Missouri against three programmers who had developed an alternative implementation of its online multiplayer server software. The defendants reverse engineered the network protocol Blizzard games use to communicate with Battle.net. From the messages sent between the game and server program, the defendants created a server program called bnetd that mimicked Battle.net's operation, enabling users of Blizzard games to play each other over the Internet without using Blizzard's proprietary online multiplayer service.
Blizzard successfully argued that the developers had contracted away their right to reverse engineer when they clicked through the games' end user license agreements (EULAs), which contained a clause prohibiting the practice. Applying California law, the court found that the EULAs were binding contracts and that the clause banning reverse engineering was not unconscionable. It also found that federal copyright law's fair use defense did not preempt state contract law, permitting the EULA to waive rights normally considered fair use under default copyright rules.
The court also held that the defendants' conduct constitued circumvention and trafficking in a circumvention device under Section 1201 of the Digital Millennium Copyright Act (DMCA). The court found that the Battle.net mode of the game software was a copyrighted work protected by a "secret handshake" technical protection measure, and rejected the developers' argument they had circumvented the measure solely for the purposes of interoperability, an exception under the DMCA.
