Portgas D Ace’s Bounty at 550 million Berries

550,000,000 is the last figure, not the first. Back when he still captained the Spade Pirates, the World Government offered him a Warlord seat. He turned it down, and that refusal on its own pushed his price past a hundred million and carried his name across the New World. Everything above that was earned under Whitebeard's flag: he took apart the New World pirate Doma and his entire crew by himself, which is what got him recommended for 2nd division commander, and later beat a sitting Warlord, Hanafuda, who lost the title over it, his seat going to Bartholomew Kuma.

The flag is the real story. The government had found out whose son he was and wanted him dead, and could not lay a hand on him while he sailed with Whitebeard. Blackbeard broke the deadlock by handing him in, and was paid with the very title Ace had refused. Then Level 6 of Impel Down, the floor kept for the worst criminals alive.

The name itself came out of Sengoku's mouth. The fleet admiral announced it from the execution platform, to the entire world at once, son of Gol D. Roger, to justify killing him and the war everyone could already see coming.

Marineford settled the rest in minutes. Akainu insulted Whitebeard, Ace turned back, burned his arm on him, then threw himself in front of a magma fist aimed at Luffy and took it through the chest. Raised on Mount Colubo by Dadan's bandits, he had dropped his father's name for his mother's and called Whitebeard the only father he ever had.