Attorney Mona Ibrahim has published an analysis of the legal implications involved in reverse-engineering games.
The article follows a hypothetical game developer who is frustrated that her favorite game has poor server support, so she reverse-engineers the network protocols to create a private, lag-free server. The concept isn't so far-fetched: guides on how to create a private World of Warcraft server abound and some reverse-engineered games, like SWGEmu have gained quite a bit of attention.
Ibrahim's article outlines the various laws and doctrines that come into play with reverse-engineering, from the Copyright Act to the Electronic Communications Privacy Act, and provides practical examples of where enterprising coders can go wrong.
For instance, regarding the DMCA, Ibrahim notes:
If Mallory's new server doesn't provide the same safeguards that control access to the original game servers (like a CD key or a version verification protocol), then her own server is circumventing access controls to the online component of the game. Therefore, by distributing the program, means (such as DIY instructions), or code to access servers that don't use the game's original access controls, she would be violating the anti-circumvention provision.
The article concludes that while reverse engineering itself is not illegal, it does run a gauntlet of legal issues and that "[t]his isn't the type of project you want to pursue if you're risk averse".
Dan Rosenthal is a legal analyst for the games industry.