The anti drain valve is within the new type of oil filters. Instead of a Fram PH13 for sbc, you now would use a PH5.

I believe this filter to be rather key when using a remote filter or external cooler due to the fact that a lot of oil could bleed back into the pan thereby causing an even longer dry start-up. This is why these filters were invented, to circumvent dry start-ups. Also to stop any debris to flow back into the pan once it has found it's way into the filter.