[graypegg]

I quite like the licensing trick Nintendo used on the gameboy as an example of this. [0]

Essentially, the gameboy expected a bitmap of the Nintendo logo to be present on the cartridge rom, and was shown on screen at boot. It had to match a version stored on the gameboy itself or else the game wouldn’t start.

The thinking (that I’m not sure was ever tested) was that someone producing a game that tried to trick consumers into thinking it was an official Nintendo product, would be liable for damages in a trademark lawsuit. Since the game would never start without an official Nintendo logo, the hope was to make the legal system enforce Nintendo’s licensing scheme.

[0] https://catskull.net/gameboy-boot-screen-logo.html

[bentley]

The thinking was tested (in U.S. jurisdiction) in Sega v. Accolade. https://en.wikipedia.org/wiki/Sega_v._Accolade

The court sensibly ruled that using technical means to force competitors to display your trademark against their will doesn’t mean you can then claim they’re infringing that trademark.

[pcwalton]

Apple tried this too with Dont Steal Mac OS X.kext, which uses a haiku with a copyright message as the key to decrypt certain executables like the Finder. I don't think it had any real-world impact.

[kevin_thibedeau]

Pretty rich considering their history with sosumi.

[radarsat1]

Also reminds me of MODULE_LICENSE and EXPORT_SYMBOL_GPL in the Linux kernel.

https://www.kernel.org/doc/html/latest/process/license-rules...