P2PK (Pay-to-Public-Key)

Pay-to-public-key is bitcoin's earliest output script, locking coins directly to a public key rather than to a hash of one. It was the format used by early coinbase rewards in 2009 and 2010, including blocks attributed to Satoshi Nakamoto, and it leaves the public key visible on the blockchain from the moment the coins are created.

How it works

A P2PK output names a public key, and spending it requires only a signature from the matching private key. Later standards moved to pay-to-public-key-hash, which publishes only a 20-byte hash and reveals the key at spend time. The distinction is invisible in daily use but decisive for long-term cryptanalysis, because an attacker can only target a key it can see.

Analyses of the blockchain generally place the total coins with exposed public keys, combining P2PK outputs and reused addresses, near 1.7 million bitcoin, a set that includes the untouched Satoshi-era rewards.

In the gold vs bitcoin debate

P2PK coins sit at the center of the quantum argument against bitcoin. A future machine running Shor's algorithm could derive private keys from these exposed public keys, and dormant coins whose owners are gone cannot be migrated to safer formats. How the network should treat them, whether to freeze them or leave them as a bounty, is an unresolved governance question with no analogue in gold.