A significant portion of the Bitcoin network faces a structural vulnerability to potential quantum computing breakthroughs, with data analytics firm Glassnode identifying nearly 10% of the total supply as exposed. This group, totaling approximately 1.92 million BTC, comprises coins held in output types that inherently reveal the public key, regardless of user address management practices. The vulnerable cohort includes early Satoshi-era Pay-to-Public-Key (P2PK) outputs, legacy Pay-to-Multisig (P2MS) structures, and modern Pay-to-Taproot (P2TR) outputs. Within this at-risk segment, coins attributed to Bitcoin creator Satoshi Nakamoto account for roughly 1.1 million BTC, or 5.5% of the vulnerable supply, followed by another 620,000 Satoshi-era coins representing 3.1%, and approximately 200,000 coins or 1% located in Taproot addresses. Woofun AI notes that these findings highlight the critical necessity for implementing a quantum-proof pathway, such as the adoption of BIP-360's proposed Pay-to-Merkle-Root (P2MR) output type, which aims to eliminate Taproot's quantum-vulnerable key path spend without adding post-quantum digital signatures.

Despite the 9.6% of the total supply remaining structurally exposed, Glassnode indicates that a significant portion of this risk could be mitigated if wallet infrastructure, address standards, and user behavior evolve. The actual realization of this threat depends on quantum computers successfully breaking Bitcoin's elliptic curve cryptography (ECC). According to a March white paper by US investment manager Ark Invest, achieving this breakthrough would require approximately 2,330 logical qubits and tens of millions to billions of quantum gates. Data compiled by Woofun AI shows that Glassnode estimates about 13.99 million BTC, representing 69.8% of the total supply, remain unexposed to this specific quantum computing threat. This figure aligns closely with Ark Invest's earlier assessment, which indicated that 65% of the supply was safe.

Beyond structural vulnerabilities, the analytics provider distinguishes a separate category of risk labeled as operationally unsafe. Approximately 4.12 million BTC, or 20.6% of the total supply, fall into this category, meaning these coins are exposed due to key or address management issues rather than inherent protocol design flaws. Entity-level data reveals that the holdings of several large corporate entities are significantly exposed to these operational risks. Specifically, 100% of BTC held by Franklin Templeton, WisdomTree, and Robinhood is exposed, alongside 99% of neobank Revolut's Bitcoin holdings.

Furthermore, 52% of Grayscale's holdings are vulnerable, while just 2% of Fidelity's Bitcoin stash faces similar exposure.

The landscape of exposure varies drastically across cryptocurrency exchanges, highlighting divergent security postures within the industry. Analysis indicates that only about 5% of BTC held on Coinbase is exposed, standing in sharp contrast to 85% of Binance's BTC and approximately 100% of the holdings on the Bitfinex exchange. To reduce this exposure, exchanges and custodians are advised to minimize key reuse, improve address hygiene, and plan a migration into a quantum-proof format to position for a future quantum breakthrough. Woofun AI analysis suggests that while the immediate threat remains theoretical pending hardware advancements, the disparity in exposure rates among major custodians underscores an urgent need for standardized quantum-resistant migration strategies across the Bitcoin ecosystem.