Samba was reverse engineered, MS somewhat tried to make it an open standard, now are agnostic to it and are still developing closed extensions. Mono became big

Samba was reverse engineered, MS somewhat tried to make it an open standard, now are agnostic to it and are still developing closed extensions. Mono became big enough, and they opensourced their own CLR, and it runs on Linux. DirectX was implemented as a compatibility layer and runs games at close to native speeds on Linux and MS dumps it for Vulkan. Or so the wish goes.