Does anyone know if the x86 emulation for ARM that Microsoft is using was created in house if licensed from a third party? If it's the later, it certainly opens

Does anyone know if the x86 emulation for ARM that Microsoft is using was created in house if licensed from a third party? If it's the later, it certainly opens for Apple to easily get their hands on the same thing for a quicker transfer not that they couldn't do it them selves if they felt it was needed(though I think they bought or licensed the technology for Rosetta).