Deathcap stats

I was playing with deathcap earlier today and got it as a first item(which I don't know if that might be the cause) and each item i got after it still didn't register any bonus ap stats on the tool tip. Wasn't sure if you guys were aware of this already. I was playing on as a champ. Which also had me questioning if his Q's ap was suppose to be part of the bonus ap when I noticed the bonus tooltip didn't show ap in the item stats section.