I've seen arguments going both ways on this so I don't know how to rule this.
If a rogue with Offensive Defense gets multiple sneak attacks in one round does the bonus AC stack?
Example: A level 5 rogue with sneak attack 3d6 uses two weapon fighting while flanking and gets two sneak attacks. Does this rogue gain +3AC or +6AC?
Best Answer
Best I can tell, Paizo hasn't made an official ruling on this. The last reference I can find of an official statement on this is from an FAQ post on their blog:
http://paizo.com/paizo/blog/v5748dyo5ld6h?Bride-of-the-FAQ-Attack
Allowing it to stack would be a bit overpowered, and I would imagine most GMs would rule this way in absence of an official ruling.