FirstCoin

The FirstCoin contract introduced a basic but important pattern: a ledger of balances associated with addresses and the ability for those balances to be transferred between participants. The implementation closely resembles the early token interface examples published in Ethereum documentation at the time, suggesting it was derived from or directly inspired by the standard token APIs shared by the Ethereum Foundation. Although minimal and unbranded, the contract established the foundational mechanics that later became formalized in token standards.

The FirstCoin contract introduced a basic but important pattern: a ledger of balances associated with addresses and the ability for those balances to be transferred between participants. The implementation closely resembles the early token interface examples published in Ethereum documentation at the time, suggesting it was derived from or directly inspired by the standard token APIs shared by the Ethereum Foundation. Although minimal and unbranded, the contract established the foundational mechanics that later became formalized in token standards.

FirstCoin is one of the earliest token contracts deployed on Ethereum mainnet, launched at block 49,853 on August 7, 2015 — just 8 days after the Ethereum genesis block. The contract was written by creator address 0x3d0768da, who deployed it alongside several other experimental contracts in Ethereum's opening days.

The source code is a near-exact copy of the "Coin contract" example from the official Ethereum Frontier Guide, the primary documentation for Ethereum at launch. The original example contract was named token; this deployment renames it to FirstCoin and hardcodes the supply at 1,000,000 rather than accepting it as a constructor parameter.

The contract implements a simple token: a mapping from addresses to balances, a sendCoin function for transfers, and a CoinTransfer event. It predates ERC-20 and has no approve, allowance, or transferFrom functions. There is no supply cap enforcement or overflow protection — both limitations typical of Solidity contracts written before best practices emerged.

A second deployment of the same contract by the same creator (0x3b4446acd9547d0183811f0e7c31b63706295f52) followed 11 blocks later at block 49,864.