Legally speaking it is owned by whomever purchased the rights to it (or might have originally retained them), I don't know if it went with something else but most people doing purchasing of such things will know what they are doing and look to include such things with it. In the unlikely event they went straight up dead company (
https://www.vice.com/en_uk/article/...d-no-games-the-gory-story-of-the-gizmondo-656 ) and took everything with them (you might find a lot of 8 bit era and older games like this) then we get the fun and games with abandonware, though it is not actually a recognised term anywhere that I know of.
At the same time is anybody likely to care? A useless SDK for a failed console based on common and now antiquated chips, something unlikely to impact any future emulation deals or anything like that*. The effort to bring a lawsuit to sue a random. Or if you prefer then early- mid 2000s era Microsoft (a litigious beast if ever there was one) saw their SDK for the xbox leaked for multiple revisions, while it was still current and actively used to develop homebrew and apparently have devs dodge the need for the expensive developer kits. If there ever was a suit we never heard of any. I am sure they would have slapped the original leakers but they did it Scene style so yeah. Similarly you can find all sorts of SDKs from Sega, Nintendo, Sony and beyond for trivially easy download that go unbothered for possibly over a decade at this point.
As a general fan of the works places like
https://tcrf.net/The_Cutting_Room_Floor ,
https://www.unseen64.net/ ,
https://assemblergames.com/ and similar efforts on our own humble forums I would like to see such a thing available for perusal.
*and if they are going to launch a civil suit then they would have to demonstrate losses.
No just no, if this was true if I wrote a hello world in c# following a guide then anyone who created the same thing and uploaded it online would be infringing on my copyright
As there are a limited number of ways to usefully do something in code then copyright tends to recognise this. It then becomes something you have to demonstrate was copied from you (if source is not available then usually any of the same bugs, same variable names, possibly disassembly that could only really have come from a quirk you did and so on and so on).
Coming the other way some countries don't recognise the ability to donate something to the public domain off the bat.
