So I currently have my surface pro 3 setup to ask me for my password if I have been away for 15 minutes. However, I noticed that even if I am away for a shorter time than that, I still need to go through my login screen. I decided to test it and sure enough, exactly 10 minutes after I closed the keyboard (and thus putting my SP3 to sleep), I turned my SP3 back on and it asks for my password. Does this happen to anyone else as well? I suggest you see for yourself. Set it to 15 minutes (Settings -> Accounts -> Sign-in Options), wait 10 minutes and let me know if it asks for your password.