The closest version is this one:
Chamberlain made garage door openers and claimed that the rolling code that opened the door protected access to their copyrighted "open the door" routine in their garage door opener... Since Skylink's replacement remotes caused that code to execute, they were bypassing the DRM. This was shot down.
There is also the lexmark one... They claimed that the numbers read out of their cartridges were a copyrighted algorithm (in a secret language!) that described how to measure the toner amount. Copying this code verbatim was copyright infringement. The courts ruled that this wasn't copyrightable because access controls weren't copyrightable (like you can't copyright a key). Even if it was an algorithm that was creative, it didn't really act like it. Lexmark was told to get lost.
Incidental note... Nintendo tried this with the gameboy and trademark law. It wouldn't load a 3rd party cartridge unless it had the nintendo logo in the ROM. Of course a 3rd party couldn't display that logo because that would be trademark infringement. Courts told nintendo that they lost the right to claim infringement when they required the use of that bitmap as an access control device.
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So, no, I wouldn't worry about losing the DMCA here. Of course, getting sued just to hassle you is another thing - Kuering could file a case they knew they'd lose.
The closest version is this one: Chamberlain made garage door openers and claimed that the rolling code that opened the door protected access to their copyrighted "open the door" routine in their garage door opener... Since Skylink's replacement remotes caused that code to execute, they were bypassing the DRM. This was shot down.
http://en.wikipedia.org/wiki/The_Chamberlain_Group,_Inc._v._....
There is also the lexmark one... They claimed that the numbers read out of their cartridges were a copyrighted algorithm (in a secret language!) that described how to measure the toner amount. Copying this code verbatim was copyright infringement. The courts ruled that this wasn't copyrightable because access controls weren't copyrightable (like you can't copyright a key). Even if it was an algorithm that was creative, it didn't really act like it. Lexmark was told to get lost.
Incidental note... Nintendo tried this with the gameboy and trademark law. It wouldn't load a 3rd party cartridge unless it had the nintendo logo in the ROM. Of course a 3rd party couldn't display that logo because that would be trademark infringement. Courts told nintendo that they lost the right to claim infringement when they required the use of that bitmap as an access control device.
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So, no, I wouldn't worry about losing the DMCA here. Of course, getting sued just to hassle you is another thing - Kuering could file a case they knew they'd lose.