B C Z
This came up last night and we sort of just ruled it on the spot in the favor of the Corp, as I was up 6-0, though I think the ruling was incorrect.
Run at data fort. Get through ice. Opponent rezzes Z Loyalty and pays an additional credit to prevent me from exposing the installed card in the fort. I would argue that since it's an access, that Loyalty doesn't work (Would function against Infiltration or Lemuria Codecracker, however).
So the question is: can it prevent me from seeing the card I access, or only when using an expose effect outside of a run?
Access does not equal Expose.
Zaibatsu Loyalty currently only protects against exposure due to these cards:
Lemuria Code Cracker