I know we're all speculating here but what is there to lose? Option 1: Sign my NDA or fuck off. Option 2: Show them everything and then they tell you to fuck off and steal your idea. At least with Option 1 you have some protection.

Different equation if you need money/investment. But if you're already up, running and growing it's easier to play hard ball and demand an NDA.

I'm not speculating about my experiences working for a couple of startups in Silicon Valley... I signed a bunch of NDAs. I have no idea what happened to the author of this article.