What does Glassnode's finding of 6.26 million

I have comprehensive data from multiple independent sources. Let me synthesize the findings.

Answer

What the 6.26M BTC figure is. On October 8, 2026, Glassnode co-founder Rafael Schultze-Kraft put the number of Bitcoin with exposed public keys at more than 6.26 million BTC, or 31.2% of circulating supply (Crypto Briefing, TradingView). This is an update to Glassnode's primary research report, "Measuring Bitcoin's Quantum-Exposed Supply" (May 20, 2026), which measured 6.04M BTC (30.2% of issued supply) exposed "at rest," with the remaining 13.99M BTC (69.8%) showing no public-key exposure (Glassnode Research). The figure has been climbing as more coins are spent and addresses reused.

What "exposed public key" means. Bitcoin's security relies on a one-way relationship: private key → public key → address. A public key is "exposed" when it is visible on-chain, which happens in two ways (Glassnode Research, Decrypt):

Why it matters for holder security. The risk is theoretical but permanent. A sufficiently powerful quantum computer running Shor's algorithm could work backward from a public key to derive the private key and move the funds. Critically, once a public key is exposed, it stays exposed forever — there is no retroactive fix. Europol's cybercrime unit stated: "Once a public key is exposed, it remains permanently vulnerable to future quantum decryption," and the only remedy is moving funds to new wallets before any attack arrives (BeInCrypto via Binance Square, KuCoin).

Practical implications for holders:

• Address reuse is the biggest controllable risk. P2PKH/P2WPKH addresses hide the key behind a hash only until you spend from them. Reusing an address after spending exposes the key. The operational bucket (4.12M BTC) is more than double the structural bucket, and it is largely behavioral — meaning it is avoidable (Yahoo Finance).
• Exchanges are a concentration point. Glassnode data shows exchanges hold ~1.66M of the exposed supply (BlockchainReporter via Binance Square). A separate analysis of Glassnode's quantum-risk dataset found Binance wallets at ~85% public-key exposure vs. Coinbase at ~5% (Bitcoin Foundation).
• Satoshi-era coins are irreducibly at risk. Roughly 1.7M BTC across ~20,000 legacy P2PK addresses have keys fully visible and can never be migrated (The Block).

The critical caveat (counterpoint). This is a future threat, not a present one. A cryptographically relevant quantum computer does not yet exist, and the fault-tolerant hardware required for a real ECDSA attack still does not exist (Mitrade). Europol itself concluded cryptocurrencies will not collapse from quantum computing, recommending "proactive defense" and a phased transition to quantum-resistant cryptography rather than immediate panic (KuCoin). The dollar figure (~$469B at the May report) is a theoretical exposure ceiling, not an imminent loss.

What a holder should actually do. The actionable takeaway is behavioral: stop reusing addresses (use fresh receive addresses per transaction), and for large holdings, consider migrating coins from legacy/reused addresses to fresh P2WPKH or P2TR addresses that have never spent. The industry is also working on protocol-level fixes such as BIP-360 for quantum-proof implementations (CoinTelegraph). Note that ~10% of supply is "structurally unsafe" regardless of behavior — those coins (P2PK, P2MS, P2TR) expose keys by design and can only be protected by migration.

Data caveats: The 6.26M figure is a co-founder's statement reported by Crypto Briefing/TradingView on Oct 8, 2026, and is not yet reflected in the primary Glassnode research page (which still shows 6.04M). The two figures are consistent in direction (exposure is growing) but differ in methodology timing (issued vs. circulating supply). I could not retrieve the full body text of the Crypto Briefing or CoinDesk articles via scraping, so the co-founder's exact quote and the AI-warning context from CoinDesk are only partially captured.

Evidence Snippets

Claim: The 6.26M BTC / 31.2% figure was stated by Glassnode co-founder Rafael Schultze-Kraft on Oct 8, 2026.

• Evidence snippet: "On October 8, 2026, Glassnode co-founder Rafael Schultze-Kraft put the figure at more than 6.26 million BTC, or 31.2% of circulating supply."
• URL: https://www.tradingview.com/news/cryptobriefing:511893dd1094b:0-glassnode-co-founder-counts-6-26-million-btc-with-exposed-public-keys/

Claim: Glassnode's primary research measured 6.04M BTC (30.2%) exposed at rest, 13.99M BTC (69.8%) not exposed.

• Evidence snippet: "By that measure, 6.04M BTC, or 30.2% of the issued supply, is exposed, while the remaining 13.99M BTC, or 69.8%, shows no public-key exposure at rest."
• URL: https://research.glassnode.com/measuring-bitcoins-quantum-exposed-supply

Claim: Exposure splits into structural (1.92M BTC) and operational (4.12M BTC) buckets.

• Evidence snippet: "Glassnode data shows 4.12 million Bitcoin (BTC) are held in quantum-exposed addresses due to address reuse, partial spending, and custody practices, more than double the 1.92 million BTC exposed by Bitcoin's older script types."
• URL: https://finance.yahoo.com/markets/crypto/articles/glassnode-finds-20-bitcoin-quantum-051408501.html

Claim: The exposed supply was valued at ~$469 billion.

• Evidence snippet: "Nearly one-third of all Bitcoin in circulation—over 6 million coins worth over $469 billion as of this writing—is already vulnerable to theft if powerful quantum computers become a reality."
• URL: https://finance.yahoo.com/markets/crypto/articles/nearly-500b-bitcoin-exposed-future-230004094.html

Claim: Exchanges hold ~1.66M of the exposed supply.

• Evidence snippet: "Glassnode Finds 6.04 Million BTC Exposed to Quantum Attack Risk, Exchanges Hold 1.66 Million of U..."
• URL: https://www.binance.com/en/square/post/326055452960578

Claim: Once a public key is exposed, it remains permanently vulnerable; migration is the only fix.

• Evidence snippet: "'Once a public key is exposed, it remains permanently vulnerable to future quantum decryption.' Owners must move those funds to new wallets before any attack arrives, Europol says."
• URL: https://www.binance.com/en-IN/square/post/374764547573814

Claim: ~1.7M BTC sit in legacy P2PK addresses that can never be migrated.

• Evidence snippet: "About 1.7 million bitcoin sit across roughly 20,000 legacy pay-to-public-key (P2PK) addresses, where the public key itself is the address and is fully visible onchain, leaving those coins directly vulnerable to a future..."
• URL: https://www.theblock.co/post/404685/coinbase-quantum-report-flags-exchange-cold-wallets-among-millions-of-bitcoin-exposed-by-address-reuse

Claim: A cryptographically relevant quantum computer does not yet exist.

• Evidence snippet: "The fault-tolerant hardware required for a real attack still does not exist."
• URL: https://www.mitrade.com/insights/news/live-news/article-3-2077697-20260911

Claim: BIP-360 is proposed as a quantum-proof implementation.

• Evidence snippet: "Glassnode identified 10% of Bitcoin supply as structurally exposed to a quantum breakthrough, underscoring the need for a quantum-proof implementation such as BIP-360."
• URL: https://cointelegraph.com/news/nearly-10-bitcoin-supply-structurally-unsafe-quantum-breakthrough-glassnode

Claim: Binance shows ~85% public-key exposure vs. Coinbase ~5% in Glassnode's dataset.

• Evidence snippet: "Binance Bitcoin wallets show 85% public-key exposure in Glassnode's quantum-risk dataset, far above Coinbase's 5% exposure."
• URL: https://bitcoinfoundation.org/news/crypto-companies-news/binance-bitcoin-wallets-show-quantum-exposure

---

Some steps didn't finish and sources may be incomplete. Ask if you want me to go deeper.