Microsoft has started hiring Linux kernel developers like Matthew Wilcox, Paul Shilovsky, and (in mid-2016) Stephen Hemminger... Microsoft now employs 12 Linux kernel contributors.
Hiring kernel developers sounds like business-as-usual for Microsoft. Go back to 1988 when Microsoft were in need a new kernel to replace DOS - OS/2. >From Wikipedia<https://en.wikipedia.org/wiki/Windows_NT>... "Microsoft hired a group of developers from Digital Equipment Corporation led by Dave Cutler<https://en.wikipedia.org/wiki/Dave_Cutler> to build Windows NT, and many elements of the design reflect earlier DEC experience with Cutler's VMS and RSX-11, but also an unreleased object-based operating system developed by Dave Cutler<https://en.wikipedia.org/wiki/Dave_Cutler> for DEC Prism." cheers, Ian.