The folks at Over The Cap have put together projections for 2015 compensatory picks, and the San Francisco 49ers could be looking at a decent haul. According to OTC, the 49ers could be in line for a 4th round pick for Donte Whitner, and a 7th round pick for Anthony Dixon. They discuss the methodology HERE.
The 49ers currently have seven draft picks in the 2015 NFL Draft, but they should add two more in the form of compensatory picks. Such picks for the 2015 NFL Draft come due to additions and departures in 2014 free agency. The idea is that if you lose more qualifying free agents than you gain, you will get comp picks. If you add more than you lose, you don't lose any picks.
The 49ers are looking at two picks because they lost three qualifying free agents, and they signed one qualifying free agents. Their gains and losses are as follows:
Gained: Antoine Bethea, Chris Cook
Lost: Donte Whitner, Tarell Brown, Anthony Dixon, Mario Manningham, Colt McCoy
OTC listed Cook and McCoy as offsetting free agents. However, I don't believe either of them qualifies in this case. They along with Manningham likely did not have enough guaranteed money. It would seem that Brown and Bethea were close enough to offset one another, leaving compensation for Whitner and Dixon.
Comp picks cannot be traded, but it does make it easier to try and move other picks since you know you have those two locked in. We will find out the exact specifics of the picks when the owners meet in late March.