In my company the person who sits on the L/H is also the PIC in that role unless it's a training flight under the supervision of a training captain. In that case the R/H seating Captain will be the PIC and will log these hours. If two captains are assigned on the flight the company will designate a "mission commander" who will act as the PIC and will seat on the Left. All captains will receive a RHS check and training and are expected to perform duties from this position as well (PF/PNF) - however it sometimes leads to silly discussions (ego maybe?) and a Captain tries to explain you why he can't sit on the right and whatsoever..