Nintendo came up with 10NES, or more commonly: the "lockout chip." In short, a chip inside the NES would query a chip in the cartridge to verify authenticity; if the cartridge lacked the corresponding part of the 10NES chip, then the game wouldn't run. Since these chips were only available from Nintendo, Nintendo had to approve a game before its publisher could acquire the chips for manufacture. It was a relatively simple system in order to make sure Nintendo had control over the games released for NES.
That's not to say it was foolproof, and as such, a number of bypass methods were used by companies that wanted to release unlicensed games. The most famous instance actually involved a bit of deception to get documentation on the chip from the Patent and Trademark Office. In any case, none of these workarounds were practical, and thus the number of unlicensed cartridges was few. In addition, Nintendo did what it could to get rid of any unlicensed titles that did see release, including suing over the aforementioned deception at the Patent and Trademark Office.
Of course, if we were to apply the laws that exist today to unlicensed game manufacturing, then there would be a new tool for console makers to take advantage of: The Digital Millennium Copyright Act (DMCA). By my estimation, one of the provisions of the act would apply directly: the anti-circumvention provision. This provision is in Section 1201. The exact language of the provision in question is: "No person shall circumvent a technological measure that effectively controls access to a work protected under this title." Exceptions are designated by the Library of Congress, but are for the most part related to archival of the material in the work by libraries when it comes to video games.
The DMCA was specifically created to make tampering with copy protection an official offense, but, based on the wording, I believe it also applies to a device like 10NES; which does not necessarily pertain to copy protection, but is concerned with access control nonetheless. Specifically, in this sense, the issue is basically the opposite kind of access control: keeping material off of a given system, rather than preventing people from changing its media. Of course, this has been essentially untested legally, and it may very well never be tested in such a sense. The modern equivalent of "breaking" the 10NES is the modchip, and regardless of your stance on modchipping, those devices are generally considered well within the anti-circumvention provisions. From that perspective, cracking the 10NES likely would be an anti-circumvention DMCA case.
For the most part, there isn't any professional creation of unlicensed games any more, and the rare exception (like Bob's Game) usually never surfaces above the homebrew scene. I'm not aware of any significant unlicensed sales at the commercial level after the SNES era, as even XNA games are bound to some regulations. That may in part be a function of the increased complexity of game development. Unlicensed games are certainly an interesting historical footnote, and great fodder for the recent proliferation of game-based internet videos.
Mark Methenitis is the Editor in Chief of the Law of the Game blog, which discusses legal issues in video games. Mr. Methenitis is also a licensed attorney in the state of Texas with The Vernon Law Group, PLLC and a member of the Texas Bar Assoc., American Bar Assoc., and the International Game Developers Assoc., where he is a board member of the Dallas chapter. Opinions expressed in this column are his own. Reach him at: lawofthegame [AAT] gmail [DAWT] com.
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