User blog comment:Kaido King of the Beasts/Chapter 809: Catfights and Mammoth-Sized Bounties/@comment-2226235-20151204035803

That bounty makes me even more curious about what Jack's done. Ace, the son of the Pirate King and one of the top commanders under the strongest man in the world, was only worth 550,000,000, which means Jack must have done something really serious to get a bounty like that. There's no way it's just based on power or his association with Kaido.