That's what they did to BlueRibbon Soundworks - makers of SuperJam! and Bars and Pipes. Until recently there were still references on their website - vague support readmes and allusions to .lha patch archives. They seem to have removed it now, though I didn't search thoroughly.
I don't know what M$ pilfered from them.
A good chunk of DirectX. (Mostly about sound and music)
