From your citation, I think it'd be valid attribution if the BIOS setup UI had a "licensing" tab, that spelled out the IP that this BIOS was derived from. (This

From your citation, I think it'd be valid attribution if the BIOS setup UI had a "licensing" tab, that spelled out the IP that this BIOS was derived from. (This is how e.g. iOS and Android do licensing: you drill down into Settings > About > Licensing and all the IP declarations are spelled out there.) Provided they had that, then the initial "vanity" copyright notice on boot would be extraneous, and they could freely change or remove it. Without that kind of thing, the on-boot notice is the "load-bearing" UI attribution, and must be retained.