Can i claim my 25 year old as dependent if he is full time graduate student with no income?

He has no income and goes to school full time in another state. He has student loans. I have read that the age limit is 24 (which he turned in 2016) but Turbo Tax is saying he qualifies as a dependent. I'm confused, why would Turbo Tax allow the dependent status if he is too old and his birth date is listed in forms?