Lawyers concerned in-house code may become virally GPL licensed (I think, it has been a while since I had insight into MS inner workings). Same sort of thing as many/most companies won't allow their employees to look at patents.

> in-house code may become virally GPL licensed

Without reusing any of that code, simply by osmosis? I don't know what the legal theory could be, but is that something that has ever happened in the entire history of the GPL?

no, by writing similar \ equal code somewhere that later other people looking at it could argue is a re-use of the GPL code they looked at and thus causing the whole project to became GPL.

it is just them thinking it is better being safe then sorry. if they don't even look at the code there is no way to argue that they are copying it.

Just a small correction/clarification - using GPL code inside a non-GPL project doesn't magically cause it to become GPL, it just means you would be committing copyright infringement if you distributed your project afterwards.

It's still something you want to avoid, but the outcome would potentially be a lawsuit from the copyright holder, rather than forcing you to relicense your project.

M$ is long time GPL hater. They use lot of GPL code, but stil hate it, because they cannot make profit from it. Commercial companies like BSD-style licenses, because they are free as in "free work".

they don't use any GPL code in stuff that they license in any other way. it isn't a matter of liking the license or not, it's a matter of license compatibility.