Davidson & Associates v. Jung, 422 F.3d 630 (8th Cir. 2005), arose when Blizzard Entertainment and its parent Vivendi sued the developers of “bnetd”, a free program that emulated Blizzard’s Battle.net online gaming service. The Eighth Circuit affirmed summary judgment for Blizzard, holding that the end user licence agreement (EULA) and terms of use (TOU) were enforceable against the developers and that the emulator violated the Digital Millennium Copyright Act (DMCA).[1] It is an early appellate ruling on a per-copy “CD key” used as an access control for online features.
Background
Battle.net was a free service, available only to purchasers of Blizzard games, through which owners could play each other online. Each authorised copy, except Diablo, shipped with a “CD Key” printed on a sticker on the case. During installation the user agreed to the EULA and TOU, both of which prohibited reverse engineering, and entered the CD Key.[1] The packaging said use was subject to the EULA, which was not printed there, and a user who disagreed could return the game for a refund within 30 days.[1]
When a user logged on, the game and the Battle.net server exchanged an authentication sequence, the “secret handshake”, and the server checked both that the CD Key was valid and whether the same key was already in use by another player on the same gateway.[1]
The dispute
A group of volunteer programmers, frustrated by Battle.net’s performance, built the bnetd server so that Blizzard games could play online without Battle.net. To do so they reverse engineered Blizzard’s protocol. The bnetd server did not check whether a CD Key was valid or in use, and always replied “okay”, so unauthorised copies could use the multiplayer features. The developers released the source code and a utility that redirected games to bnetd servers, and others built further emulators from it.[1]
Blizzard and Vivendi sued in the Eastern District of Missouri. A consent decree and permanent injunction resolved the copyright and trademark claims, leaving the DMCA claims, breach of the EULA and TOU, and the developers’ counterclaims. The district court granted summary judgment for Blizzard on those.[1]
Decision or outcome
The Eighth Circuit held that:
- Contract. The Copyright Act did not preempt the contract claims. By accepting the EULA and TOU, the developers had agreed not to reverse engineer, and the court relied on a Federal Circuit decision that parties may contract away limited reverse-engineering rights. At argument the developers had conceded that the only remaining issue was conflict with the DMCA interoperability exception.[1]
- Anti-circumvention. The CD key “secret handshake” was a technological measure that effectively controlled access to the games’ Battle.net mode, and bnetd allowed access without a valid or unique key. The court distinguished a Sixth Circuit printer-cartridge case, because here the control measure was not freely available and reaching its code needed reverse engineering.[1]
- Anti-trafficking. The emulator had a limited commercial purpose beyond avoiding Battle.net’s controls, and was designed to circumvent them.[1]
- Interoperability. The exception failed because the circumvention constituted infringement: it let unauthorised copies be played freely.[1]
Significance for software licensing and SAM practice
- Keys validated by a server are access controls. The court tied DMCA protection to the server’s check of key validity and concurrent use.[1]
- Click-through terms were enforced. Users who clicked “I Agree” were held to the reverse-engineering ban, although the full terms were not on the box.[1]
- Concurrent-use checks can be bypassed by third-party tools. The emulator never asked whether a key was already in use, which is the kind of control a licence manager relies on.[1]
Lessons learned
- A CD key checked by the vendor’s server can be an access control protected by the DMCA. The court affirmed liability for a free tool that skipped the check.[1]
- Click-through bans on reverse engineering were enforced. The court found the developers had expressly relinquished their rights to reverse engineer.[1]
- The interoperability exception does not apply where the circumvention enables infringement. Play with unlicensed copies defeated the defence.[1]
- Per-copy keys verified and tracked for concurrent use are part of controlling licensed use online. The server checked validity and simultaneous use of each key.[1]