Patents may be selectively enforced, there's no forfeiture as there is with trademarks. Intel had (and has) no issue with qemu or bochs emulating everything, a

Patents may be selectively enforced, there's no forfeiture as there is with trademarks. Intel had (and has) no issue with qemu or bochs emulating everything, as long as they were niche and/or promoting the Intel platform (and grudgingly accepting compatibles). However a move to rid Microsoft's platform from Intel altogether without compromising compatibility is something worth fighting for. I heard that ARM is rather similar in that aspect: emulators for development are a-ok, but trying to run ARM emulation on a consumer product with no ARM components inside will drive up the legal fees until some licensing agreement is set up.