They asked me (through recruiter) to do a coding exercise on my own time. I spent about 10 hours and submitted, then no response at all. My recruiter later told me they thought my code was good, but they had filled the position or something. I have to say, if you knowingly ask candidates to spend so many hours on an exercise, you should be seriously about it. Do not ask candidates to do this if you have decided, or very likely, to hire someone else, or let candidates know as soon as the role is filled, so they don't have to waste so much time. Respect candidates' time. It's just as important. Complete waste of time. Very negative experience.