G7 Warns Quantum Computing Could Threaten Bitcoin’s Cryptographic

The Group of Seven has warned that sufficiently advanced quantum computers could eventually compromise cryptographic systems used across the financial sector, raising renewed concerns about Bitcoin holdings whose public keys are already exposed on the blockchain.

The warning was highlighted by Coin Bureau in a post on X, which cited the G7’s cybersecurity work on the transition to post-quantum cryptography. The G7 Cyber Expert Group has urged financial authorities and industry participants to prepare for quantum-related risks and develop migration strategies toward quantum-resistant cryptography.

G7 Pushes Financial Sector Toward Post-Quantum Security

The G7 Cyber Expert Group’s January 2026 roadmap does not specifically target Bitcoin. Instead, it addresses the broader s system and warns that sufficiently advanced quantum computers could compromise widely used public-key cryptographic protocols protecting financial infrastructure and data.

The group recommends that financial institutions, technology providers and other critical infrastructure operators begin preparing for the transition. It also emphasizes cryptographic agility, allowing systems to replace vulnerable algorithms as quantum technology develops.

The issue has direct relevance to Bitcoin because some coins are associated with publicly exposed cryptographic keys. Coin Bureau cited an estimated 6.9 million BTC in addresses with exposed public keys, including approximately 1.1 million BTC believed to be associated with Bitcoin creator Satoshi Nakamoto. The latter holdings would represent more than $80 billion based on the figure cited in the original post.

Independent research has also identified the scale of the exposure as significant. Glassnode estimated in May that 6.04 million BTC, or 30.2% of issued supply, had public-key exposure at rest, although estimates vary according to methodology.

BIP-360 Offers a Potential Bitcoin Migration Path

Bitcoin developers are already working on defenses against future quantum attacks. BIP-360 proposes a new Pay-to-Merkle-Root output type designed to remove the quantum-vulnerable key path associated with Taproot while providing a more resistant address format. The proposal remains a draft rather than an activated Bitcoin consensus change.

The debate extends beyond technology to governance. Proposals to deal with coins that remain in vulnerable addresses, including long-dormant holdings attributed to Satoshi, have raised difficult questions about whether the network should eventually restrict or freeze those funds.

That question could become one of Bitcoin’s most consequential protocol debates if quantum computing advances faster than holders migrate exposed coins. For now, the G7’s roadmap provides a broader financial-sector deadline for preparation, while Bitcoin developers continue evaluating BIP-360 and other potential defenses.

Writer: Victoria Hale
Technology & Blockchain Writer

Victoria Hale writes about blockchain technology, digital infrastructure, and the intersection of emerging technologies with finance. Her articles explore how new protocols and systems are shaping the evolving digital economy.

She prioritises clarity and accuracy when explaining technical developments to a general audience.