Renowned Cryptographer Says His Patent Was an Obstacle for Hal Finney

Tatsuaki Okamoto explains why his "Electronic cash" patent might have presented an obstacle to Hal Finney in his ambition to create his own electronic currency.

Six key patentsSometime before Dec. 6, 2004, Hal Finney did a search in a patent database on "Blind-signature based cash systems".

Four of the patents are authored by David Chaum, the other two by Okamoto and his colleague at Nippon Telegraph Kazuo Ohta.

Okamoto currently serves as director of the Cryptography & Information Security Lab at NTT Research and holds over 100 patents.

We asked him to explain why his patent might have presented an obstacle to Hal Finney and other cypherpunks in their ambition of creating a decentralized currency, considering that his patent involves an intermediary.

Okamoto's ecash & Nakamoto's BitcoinOkamoto kindly prepared diagrams elucidating the differences between the ecash system outlined in his patent and Bitcoin.

In Okamoto's proposal, a trusted party varies transactions, whereas Bitcoin is trustless, with all nodes verifying transactions.

Trustless system - no trivial achievementConsidering this key difference, one might ponder - why Finney and other pioneers were so paranoid about patent infringement? One obvious answer is that Satoshi Nakamoto's Bitcoin proposal was the first successful framework for a trustless electronic cash system.

Did "Okamoto" give ideas to Finney for "Nakamoto?"Many believe Finney to be Satoshi Nakamoto or at least part of the team that was behind the moniker.

Okamoto told Cointelegraph that he was never a part of the famous cryptographic mailing lists and did not know Hal Finney personally.