Technically speaking the same Board of Directors is represented 4 times within that hierarchy, including the entity Microsoft is invested in which is one of the two entities that have investors in them and which still have a fiduciary duty to their shareholders, even as subsidiaries of the non-profit.
That’s where a lot of Microsoft’s leverage lies if it came down to a lawsuit over the last couple of weeks. If Microsoft wants a board seat, they’re going to get a board seat one way or another.