What is the exact technical reason why DirectX 12 is only on Windows 10?

[Perttu Lehtinen]

What prevents DirectX 12 from being installed on Windows 7 and Windows 8? Or is it just a traditional trick to force people on Windows 10?

 

[Zachary Boddy]

There's no real technical reason. It wouldn't be easy to get it on either Windows 7 or Windows 8, but it is technically possible as far as I know. The reason is exclusivity.

 

[Dewg]

There are changes to the Windows 10 Display Driver Model: https://msdn.microsoft.com/en-us/library/windows/hardware/Dn932171(v=VS.85).aspx

It may be that some elements of DX12 rely on those changes. I recall in the past that versions of DX were back ported to old Windows, however I think only elements of DX made it back, not the entire architecture.