According to a post by an administrator on Pandemic Studios forums...
"As of right now I can say Battlefront 3 is not currently at Pandemic. While I know the title seems to be up in the air from all the buzz around the web... Lucas Arts will be the only one knowing where the title is at right now."
http://www.pandemicstudios.com…ic.php?pid=603741#p603741
So now I have no clue who could be developing this game.
