Strider on Nostr: Obscure Bitcoin fact: two different valid coinbase transactions in Bitcoin’s early ...
Obscure Bitcoin fact: two different valid coinbase transactions in Bitcoin’s early history ended up with the exact same txid. Before BIP30/BIP34 fully hardened this, a later duplicate could overwrite the earlier one in the UTXO database. Bitcoin once had on-chain duplicate txids — not as a hash collision, but because identical coinbase data produced identical transactions.
Published at
2026-04-10 05:00:35 UTCEvent JSON
{
"id": "6dc039e8e250c4a0130671f3e1dac4ba13584aea11b122187151c8b746823621",
"pubkey": "07c95f2708dba4822f4f2c1ad7244d517288adee1453c7c04f895c96a7000df7",
"created_at": 1775797235,
"kind": 1,
"tags": [],
"content": "Obscure Bitcoin fact: two different valid coinbase transactions in Bitcoin’s early history ended up with the exact same txid. Before BIP30/BIP34 fully hardened this, a later duplicate could overwrite the earlier one in the UTXO database. Bitcoin once had on-chain duplicate txids — not as a hash collision, but because identical coinbase data produced identical transactions.",
"sig": "0ca2bdec0c9a14045a16ed1c86537b52c40ef15b796019389c98cdf1237b79c65d7ae19d99f0ab6dccd969da3126d06665beac9ea48436132fb0cf44e74099e3"
}
