Let's say that, in completely open ground (i.e., no actual physical cover anywhere nearby), a creature with reach is immediately adjacent to a foe. That foe's ally is immediately behind the foe, within reach of the creature, as such:
C <-> F1 <-> F2
Foe #2, who has soft cover from the creature, does some action that would normally provoke an attack of opportunity from the creature. The rules seem to state rather clearly that any entity which has "cover" cannot be the target of an attack of opportunity through the "cover". However, the mention of "soft cover" comes after that. In this particular instance, is "soft cover" merely a specialized case of "cover" for which all rules regarding normal cover apply, including the protection from attacks of opportunity? Or is "soft cover" a completely independent rule to "cover" and gives only the bonuses / penalties stated in its own entry (ranged AC bonus only).
Update (3/25/2014): I'm not entirely satisfied with the one answer (from Lord Gareth) provided so far to this question. Though it may be correct, it does not provide enough explanation to convince me. I would also like to formalize my comment to that answer within the question.
Note that in the second paragraph under the main heading of "Cover" in the linked article above, there is this sentence: "When making a melee attack against a target that isn’t adjacent to you (such as with a reach weapon), use the rules for determining cover from ranged attacks." So, attacks against non-adjacent targets are treated as range attacks for the purposes of determining cover, and soft cover specifically mentions that it provides cover against ranged attacks. Does that mean
- AoO's are blocked, or
- targets of the AoO get a +4 AC bonus, or
- resolve AoO normally?