Atlus USA has released a statement regarding concerns that Persona 4 Arena will be region-locked. Yes, they confirm, it will be. But they assure that this will not become a trend and that " multiplayer is global, a fact that is in no way affected by the region-lock. Players can compete against fighters from all territories."
The rationale behind the region locking had to do with cost more than anything. Atlus, concerned that Japanese players might import North American copies, encoded the game. Standard retail price for the game in Japan is 7,280 yen; a North American version of the game before shipping is 4,780 yen (amounting to about a $30 difference).
The statement reads,
"The unforeseen consequence in all of this was that we had a version of our biggest game of the year releasing within a couple weeks in two territories, both identical in content, but at radically different price points. Importing, as great as it is for gamers who otherwise can’t get access to a title, can also cannibalize the performance of a title in one territory to the benefit of another. While we’re all one big ATLUS family, the reality is that the dramatic difference between the Yen and the Dollar makes for a dramatic difference in price. So the decision was made, perhaps at the expense of some of our fans, clearly at the frustration of many, to region-lock Persona 4 Arena."
You can read the rest at the link below.