It's all based on region. Something like 400k for NA and Europe, and 200k for Japan. Then the game also has to have been out for at least 9 months or something like that.
Though sometimes more niche games slip through the cracks a long time after they've released, like Okami and Disgaea. I'm not sure if Capcom/NIS worked out a deal with Sony for those or if the requirements for ps2 games in NA changed after the ps3 started picking up steam.







