Documented history · January 12, 2009

Ten BTC Between Two Computers

In Bitcoin’s first days there were no exchanges, market price, stores, or familiar wallets. The software ran and blocks appeared, but one question remained: could one person really transfer bitcoin to another? Block 170 supplied an answer.

The person who ran the software

Hal Finney was a programmer and cryptographer. He had worked on PGP, created Reusable Proof of Work, and participated in the cypherpunk community.

When Satoshi announced the first Bitcoin release, many readers were skeptical. Finney chose to test it. He later recalled that he was probably the first person after Satoshi to run Bitcoin.

The software still had bugs. Finney reported problems; Satoshi fixed them and sent updated versions.

The first transfer

On January 12, 2009, Satoshi sent Finney 10 BTC. Finney described it as a test. The transaction identifier is f4184fc596403b9d638783cf57adfe4c75c605f6356fbc91338530e9831e9e16.

Its input spent 50 BTC previously created through mining. Ten BTC went to Finney, while 40 BTC returned to the sender as change. The fee was 0 BTC.

This was not the blockchain’s first record: earlier blocks already contained special transactions creating mining rewards. Block 170 is, however, considered the first known bitcoin transfer from one participant to another.

What the test established

Those 10 BTC did not yet have a widely accepted market price. Finney did not sell anything to Satoshi. The transaction therefore did not prove that Bitcoin had become money or acquired market value.

It tested something narrower but essential: one computer created a transfer, another received it, the network placed it in a block, and both participants observed the same history.

Until then Bitcoin existed as software and rules. The transfer supplied a documented example of those rules moving value between two people.

What the blockchain did not preserve

The blockchain shows amounts, timing, inputs, and outputs. It does not contain the correspondence between Satoshi and Finney, their doubts, or the reasons behind every decision.

We know the purpose of the transfer because Finney later described it. Without his account, the movement of 10 BTC would remain visible, but the people behind the keys and the purpose of the transfer would be far less certain.

Hypotheses for discussion

A network begins with two participants

A decentralized network may begin not with millions of users but with two people willing to test one another: one publishes the software, and another decides to run it.

Bitcoin’s first value was verifiability

The 10 BTC had no stable exchange rate. Their early significance may have been that the transfer could be independently observed and checked.

A public transaction does not automatically reveal identity

Finney’s account connects this transaction to him and Satoshi. The blockchain itself shows keys and amounts, not passports. These are interpretations, not proof of Satoshi’s identity or of the transfer’s economic value.

The blockchain preserves actions, while their human meaning often survives in letters, forums, and memories.

Historical and educational material. The hypotheses are separated from documented facts and do not prove Satoshi’s identity, the value of 10 BTC, or the complete content of the participants’ correspondence.

Unless stated otherwise, the text, conclusions, structure and editorial arrangement were created by the project editors. Facts, quotations and source materials remain attributable to their authors and rights holders.