content: Unlike Linux there is no corporate use of ReactOS yet. So no reason to sue yet. http://techrights.org/2016/02/10/extorting-acer-with-patents/ Microsoft has sued over Linux before, using SCO as a proxy to sue. Claiming Linux has SCO Unix code in it, which was proven false and tried to make each Linux user pay a $35 licensing fee to use Linux. https://en.wikipedia.org/wiki/SCO/Linux_controversies ReactOS once had a code audit when it was rumored they used Microsoft Windows source code:  https://www.reactos.org/wiki/Audit ReactOS is still in the alpha phase so not ready for prime time yet.