This post actually comes from MRM420 but he's at work and this has to go up now.
Both Ben and Lock were chosen as leaders because they both had similar beginnings and were perhaps both led to believe that they were special. Nemesis needed Lock so that he could use his body to convince someone else to kill Jacob. But he needed to make sure that "that someone" would definitely go through with killing Jacob, so Ben was groomed as leader long before Lock ever came to the island so that he would lose his leadership to Lock, grow to hate Lock, eventually kill him and so on and so forth. It was all part of the plan.
If this is the case then we could reason that Richard is indeed working for Nemesis. As it was him who lured Ben to become leader and it was him who was determined to get Lock to be the new leader . (remember the man from Talahasi) Richard gave Lock what he needed (Sawyer's bio) to kill his father in order to get the Others on his side, all of this behind Ben's back. They were both played by Nemesis AND Richard.