[lucio]

If that holds. Intel will sue AMD into the ground. "The 8086 API and instruction set, is an original, curated taxonomy of classes, methods, and interfaces, organized by authors"

[nimrody]

They did sue. But since AMD was originally a licensed second source for 8086 -- they failed (https://en.wikipedia.org/wiki/Second_source)

[ignaloidas]

AMD would have rights to sue back saying that "The x64 API and instruction set, is an original, curated taxonomy of classes, methods, and interfaces, organized by authors", as they extended x86 to 64 bits, and then had similar with x86 cross licensing agreements with Intel.

[hajile]

There's a cross-license agreement in place there that would certainly cover such case -- even if they were ruled to be implicit.

[stingraycharles]

This is important: this shows that AMD and Intel agree that these instruction sets are indeed protected and should be licensed.

[pgeorgi]

And yet there's fx!32 (WinNT for Alpha), x86emu (of XFree86), Bochs, VMware, parallels, Plex86, QEMU plus numerous other implementations of i386+ in software (one of them shipping in Windows 7 and newer to run PCI Option ROMs) where nobody seems to care too much.

OTOH, ARM was rather adamant about not wanting to see ARM instruction set implementations in software for a long time.

Either they saw the value in these emulators existing so that changed their minds - or somebody didn't let themselves be bullied into compliance: just because a company threatens you with lawyers doesn't mean they actually have a case.

[ghaff]

Interfaces in general have been protected. Certainly mechanical interfaces can be. But it's usually protected through patents in the physical world.