Gameboy Dev Manufacturer Code

Not sure if this is needed but most of the documentation I've looked up specifies this code as unexplained. Over the last day I've been working on a small project and started looking into the Gameboy and wanted to release my notes. It offers a way to correct the header title and output the code if present. On my library this method has been shown to work on all of the files. Added some other small notes on ideas of why/how the codes were generated.

 

After a bit more looking the function described handles a bit under 100%, a possible hash lookup will be required for the hand-full that don't follow the manu code layout.
Basically a blacklist can be made to ignore these codes if they show up, since there is so few.

EDIT:
Original document updated with new info