Bitquery Reports 96,000 Fake Address Outputs in Bitcoin's Unspent Database

A study conducted by Bitquery has uncovered that Bitcoin's unspent transaction output (UTXO) set is clogged with approximately 96,231 fake address outputs. This analysis, which scanned 965,135 blocks, highlights the inefficiencies introduced by these outputs, which are classified as unspendable.

According to the findings, these fake address outputs stem from 3,286 transactions and collectively hold around 3.2 BTC. Unlike OP_RETURN outputs, which do not burden the UTXO set, these fake addresses appear to be spendable but lack any corresponding private keys, leading to their classification as effectively unspendable.

The report also noted that the Bitcoin Core 30.0 update, released in October 2025, facilitated larger OP_RETURN transactions, which may have contributed to the increase in such outputs. However, the study emphasizes that the presence of fake address outputs poses a persistent challenge for Bitcoin nodes, as they continue to occupy space in the current node state unless they are spent.

Bitquery's research sheds light on the ongoing debate regarding the impact of various output types on the Bitcoin network, particularly in terms of node efficiency and transaction costs.