You might be thinking of the "obviousness test" for patents. If an invention is a combination of two things which are established prior art, and there is a sugg

You might be thinking of the "obviousness test" for patents. If an invention is a combination of two things which are established prior art, and there is a suggestion, teaching, or motivation which any person could discover through straightforward analysis of the existing prior art, then it's not a patentable innovation. There being one right way to solve a problem, doesn't really change whether a bit is copied or not. If you have a bug and there's one right way to solve the issue, then you don't need to copy the original. You can reproduce the bug and solve the issue, and any similarity between the independent solutions is coincidental. If you take the source code and accept the new license terms, I think you'll be bound by the terms. I am not a lawyer and I haven't read the full text of the BUSL-1.1 but I will now, since that's probably the best way to understand what the license does or does not do.