It appears another "gigaleak" has gone down, involving Nintendo. According to sources online, it appears that Game Freak has been hacked, resulting in internal data from the company being leaked to the public. Those involved in the hacking community or those within general Pokemon related groups...
Maybe this was an intentional leak. Now the Nintendo lawyers can claim they’ve used stolen proprietary code?
Copyright of code doesn’t work that way. Now if some idiot goes and uses that code in a game, yeah, they’d have a rough time in court.
If Nintendo thought there was infringement already, and wanted to prove it in court, there are means to securely prove it with redactions and NDA’s and so forth as it would be considered trade secret.