It is patience, but be careful with the third arb. I had a guy with 98 patience and he demanded free agency after I signed him to a third arb. Had a guy with 52 patience who won't even re-sign the year before he is eligible for free agency. So, it is definitely the patience rating. But, I don't know the thresholds. Just be prepared for a player to demand free agency, if he has low patience. Especially if he is a comp pick type player.