What he said... with one addition. Not only does the company's OPSPECs have to require two pilots, but you must also have a current PC to log the time as SIC. This means a current 135.293 check every 12 months. Some companies will even do a 61.57 ride on the 6 month interval (in our case, the Check Airman is there to do the Captains .299 rides anyway, so he gives us an IPC at the same time.)