In chapter 69 (Chuunin Exam semi-finals, after Sasuke's fight) or so on page 10, Oro talks about Kakashi's sharingan. I'm not exactly sure what it says because the one I have isn't scanned by a group I particularly trust, but I got the implication from that that Oro had something to do with Kakashi's three dotted Sharingan or at the very least knew a lot about it.