the Battle.net service to allow players to determine whom they wished to interact with on the
Battle.net service.^996 The court noted that these Battle.net mode features were “accessed from
within the games themselves,” which seems to mean that there was particular code within the
Blizzard games that allowed them to operate in Battle.net mode and communicate with the
Battle.net servers.^997
The Battle.net service was designed to prohibit access and use of Battle.net mode by
unauthorized or pirated copies of Blizzard games. In particular, in order to log on to the
Battle.net service and access Battle.net mode, the Blizzard games were designed to initiate an
authentication sequence or “secret handshake” between the game and the Battle.net server based
on the “CD Key” of the game, a unique sequence of alphanumeric characters that was printed on
a sticker attached to the case in which each game was packaged. The game would pass the CD
Key to the Battle.net server, which would verify its validity and determine whether the same CD
Key was already being used by another game that was currently logged on to the server. If the
CD Key was determined to be valid by the server and not already in use, the server would send a
signal to the game allowing it to enter the Battle.net mode and to use the Battle.net gaming
services.^998
In order to install a copy of a Blizzard game, the user was required to click acceptance of
a clickwrap license agreement that prohibited reverse engineering of the software and that
required the user to agree to the Terms of Use of the Battle.net service, which prohibited
emulation or redirection of the communication protocols used by Blizzard as part of Battle.net
service for any purpose.^999
The defendants developed a server, known as the bnetd server, that was designed to
emulate the Battle.net service so as to allow players to play their Blizzard games in an online
multi-player mode through the bnetd server.^1000 In order to develop the bnetd server, the
defendants had to reverse engineer the Blizzard games to learn the Battle.net protocol. In
addition, because Blizzard games were designed to connect only to Battle.net servers, the
defendants had to modify a computer file in the Blizzard games containing the Internet address
of the Battle.net servers so as to cause the games to connect to a bnetd server instead. The
defendants distributed a utility known as “BNS” that modified such file and caused Blizzard
games to connect to the bnetd server rather than the Battle.net server. Once connected to the
bnetd server through the modified Internet address file, a Blizzard game would send its CD Key
to the bnetd server. When the bnetd server received the CD Key, unlike Battle.net, it did not
determine whether the CD Key was valid or currently in use by another player. Instead, the
bnetd server would always send the game an “okay” reply. Thus, both authorized as well as
(^996) Id.
(^997) Id.
(^998) Id. at 1169.
(^999) Id. at 1169-71.
(^1000) Id. at 1172.