You can be claimed as a dependent for tax purposes by a parent if:1. You are under age 19 at the end of the year, or under age 24 and a full-time student, or permanently and totally disabled, and2. You lived with that parent for at least half of the year (counting time spent temporarily absent from the home, i.e. at school), and3. You did not prmore than half of your own support.I bring that up just in case your mother - who you did not mention - meets all of those requirements. Note that the support requirement is only that you don't prmore than half of your own support - and not that the claiming parent does, so it's possible that you may still be your mother's dependent.Assuming that's not the case, then yor father, as a nonresident alien, would not generally be allowed to claim any exemption for dependents (assuming he has a US tax obligation). He might be able to do so if you qualify as his dependent otherwise and he is a resident of Canada or Mexico, but that's an unusual circumstance.On the W4 it doesn't really matter that much, claiming 1 instead of zero only means that the employer will withhold less in taxes, and many people report a different number than the allowance calculator (which the IRS doesn't see) computes. What does matter is that you know your dependency status for the year when it comes time to actually file your return. If you can be claimed as a dependent on someone else's return, you cannot claim your own exemption - even if that other person does not claim you.