This _may_ have been the default, knee-jerk guidance for the Windows team, or part of it, but it was certainly not true for the whole of Microsoft, even back in

This _may_ have been the default, knee-jerk guidance for the Windows team, or part of it, but it was certainly not true for the whole of Microsoft, even back in 2010. In 2010, Microsoft was shipping a handful of cross-platform tools that we built and tested on Unix platforms including Mac and Linux, where it's literally impossible to avoid using GPL software. Today, Microsoft ships even more cross-platform tools (Visual Studio Code) where again, it's required to use GPL tools, and we contribute to others. (I hack on GPL code as part of my job at Microsoft.) Now, of course, you're right that this was much harder within Microsoft five years ago. And one's risk exposure is different depending on the product portfolio you own (with something like Windows being less risk averse than something like Microsoft Bob). But some very key lawyers with their heads screwed on straight have overhauled our system and it's much, much easier to deal with OSS than it was five years ago. But even then it was certainly _possible_ and actively happening in parts of the company.