The fake blueprints Iceberg fed CP9 carry the inscribed designer names “Tom. Iceberg. Cutty Flam.” — and Franky’s background had been established (across the Water Seven arc) as conspicuously untraceable.
The payoff
(Paid off on-page in the same chapter — a tight chekhov-explicit deduction.)
Earliest known caller
(unrecorded)
Why this matters
A dossier/inscription-driven explicit reveal: Oda plants the answer in plain text (the designer names on a prop the characters are literally holding) and lets the antagonists do the deductive work on-page, simultaneously delivering Franky’s origin, the Tom-apprentice lineage, and the Pluton-blueprint custody in one stroke. It consolidates the cyborg/untraceable-background tells (Franky Not A Devil Fruit User Cyborg Durability Tell) into Franky’s load-bearing backstory and converts him from a Water Seven gang-boss antagonist into the future heir of the Ancient-Weapon plans. Cross-link Franky, Tom, Ancient Weapons.