To the top... More details just in case the problem description wasn't clear enough.
1) I installed a new home-depot version catch can on the passenger side, between the PCV and the throttle body
2) It partly works, I can see oil getting inside the can
3) But the throttle body is generating so much negative pressure (ie sucking power) that oil is SUCKED OUT of the catch can and goes inside the TB.
By negative pressure, I mean from the valve cover to the TB.