(Usual disclaimer: IANAL, just a person who's worked / consulted several places and signed several NDAs in his life.) Here's the thing: the NDA you sign when y

(Usual disclaimer: IANAL, just a person who's worked / consulted several places and signed several NDAs in his life.) Here's the thing: the NDA you sign when you go onsite covers the company's intellectual property. It might cover the interview questions they ask you, but if they're not paying you for the work you do as part of a take-home interview question, and if you're doing it on your own hardware - it's not theirs, it's yours, and they have absolutely no say in what you do with that work afterwards. Moreover: if you are subsequently hired by the company, they still don't own the work you did on your own time and hardware. (However: if you continue to work on it while employed by them, they might then own that follow-up work. Check your employment contract carefully, and if you're in a position to insist that employers do not own your off-hours work, insist away.) Now, if you're currently at another company, and you complete the interview task on their hardware, and especially if you make the mistake of doing that work during company work hours...well, your current employer might then own your interview work. This is a matter usually covered by your employment contract (and another excellent reason to read those carefully).