1. Vulnerability of P2PK vs. Modern Outputs
Published 7/6/2026, 4:35:29 PM
The quantum computing threat to Bitcoin’s Pay-to-Public-Key (P2PK) outputs has transitioned into a tangible positioning risk as of July 2026. While a cryptographically relevant quantum computer (CRQC) capable of breaking ECDSA-256k1 signatures does not yet exist, institutional reallocation, timeline compression in hardware roadmaps, and the emergence of "Harvest Now, Decrypt Later" (HNDL) strategies have forced a market discount on legacy Bitcoin holdings.
1. Vulnerability of P2PK vs. Modern Outputs
P2PK outputs are uniquely vulnerable because they expose the raw public key directly on the blockchain. In contrast, modern P2PKH (Pay-to-Public-Key-Hash) addresses only reveal the public key hash; the actual public key is not exposed until a transaction is initiated, providing a layer of protection against Shor's algorithm until the moment of spending [Source: https://www.investing.com/news/cryptocurrency-news/quantum-computing-threat-to-bitcoin-p2pk-outputs-market-risk-analysis-2026].
As of 2026, approximately 6.7 to 6.9 million BTC (~32–35% of supply) is stored in quantum-vulnerable addresses, valued between $440B and $745B [Source: https://www.investing.com/news/cryptocurrency-news/quantum-computing-threat-to-bitcoin-p2pk-outputs-market-risk-analysis-2026].
| Category | BTC Amount | Risk Profile |
|---|---|---|
| P2PK (Legacy) | ~1.7M BTC | Highest: Public keys permanently exposed. |
| Satoshi-era Coins | ~1.1M BTC | Critical: Subset of P2PK; movement would trigger panic. |
| Reused Addresses | ~3.5M BTC | High: Public keys exposed after first spend. |
| Lost/Dormant | ~1.7M BTC | Irreducible: Owners cannot migrate to quantum-resistant addresses. |
2. Evidence of Market Positioning Risk
Market data from early 2026 indicates that sophisticated investors are actively pricing in this risk:
- Institutional Exits: In January 2026, Christopher Wood (Jefferies) removed Bitcoin from a major model portfolio, citing the quantum threat to cryptographic foundations [Source: https://www.investing.com/news/cryptocurrency-news/quantum-computing-threat-to-bitcoin-p2pk-outputs-market-risk-analysis-2026].
- Relative Underperformance: Bitcoin underperformed gold by ~6.5% year-to-date in early 2026, while gold surged ~55%. The BTC/Gold ratio has declined to approximately 19 BTC per ounce [Source: https://www.investing.com/news/cryptocurrency-news/quantum-computing-threat-to-bitcoin-p2pk-outputs-market-risk-analysis-2026].
- Sentiment-Driven Volatility: Academic research published in June 2025 found that conventional cryptocurrencies exhibit immediate negative returns and increased trading volume following major quantum computing news [Source: https://www.investing.com/news/cryptocurrency-news/quantum-computing-threat-to-bitcoin-p2pk-outputs-market-analysis-report-2026].
- Prediction Markets: Polymarket odds for Satoshi Nakamoto moving coins in 2026 rose to 9.3% (up from 4.5%), reflecting increased uncertainty regarding the security of early P2PK outputs [Source: https://www.investing.com/news/cryptocurrency-news/quantum-computing-threat-to-bitcoin-p2pk-outputs-market-analysis-report-2026].
3. Timeline Compression and Hardware Status
The "Q-Day" window (when quantum computers can break current encryption) has narrowed due to significant breakthroughs:
- Qubit Counts: IBM’s 2026 roadmap targets the Kookaburra processor (4,158 qubits). While breaking ECDSA-256k1 was previously thought to require millions of physical qubits, Google research in March 2026 suggested a 20-fold reduction, potentially requiring fewer than 500,000 physical qubits [Source: https://www.investing.com/news/cryptocurrency-news/quantum-computing-threat-to-bitcoin-p2pk-outputs-market-pricing-analysis-2026].
- Regulatory Urgency: U.S. Executive Order 14411 (June 2026) mandated federal migration to post-quantum cryptography (PQC) by 2031, signaling to markets that the threat is a medium-term certainty rather than a long-term theory [Source: https://www.investing.com/news/cryptocurrency-news/quantum-computing-threat-to-bitcoin-p2pk-outputs-market-pricing-analysis-2026].
4. Mitigation and Governance Bottlenecks
Bitcoin has begun technical preparations, but governance remains a risk factor. BIP-360 (P2QRH), which introduces quantum-resistant address types (bc1z), was merged in February 2026 [Source: https://www.investing.com/news/cryptocurrency-news/quantum-computing-threat-to-bitcoin-p2pk-outputs-market-pricing-analysis-2026]. However, the "Satoshi Dilemma" persists: there is no consensus on how to handle the ~1.7M BTC in dormant P2PK wallets that cannot be migrated by their owners. Proposals to "freeze" these coins to prevent a quantum-led collapse are considered "politically radioactive" within the community [Source: https://www.investing.com/news/cryptocurrency-news/quantum-computing-threat-to-bitcoin-p2pk-outputs-market-pricing-analysis-2026].
Conclusion
The quantum threat to P2PK outputs is an active positioning risk, evidenced by institutional capital shifts and a measurable "quantum discount" relative to gold. While the technical break of ECDSA is likely years away, the HNDL (Harvest Now, Decrypt Later) strategy and the potential for governance paralysis regarding dormant coins are currently influencing Bitcoin's market valuation.