Bitcoin public-key exposure reaches 35.4%, reviving quantum debate

Bitcoin’s publicly exposed supply has reached 7.12 million BTC, or 35.4% of issued coins, according to Glassnode, renewing discussion about which holdings a future quantum computer could target. Summary Glassnode puts Bitcoin held behind visible public keys at 7.12 million BTC. Address reuse accounts for 25.8% of supply, including 11.6% held on exchanges. Bitcoin’s quantum proposals remain drafts, with separate plans for exposure reduction and signature migration. Glassnode said in its Nov. 10 X post that more than a third of Bitcoin’s supply now has a visible public key, publishing a chart that separates exposure by address type and reuse. Its exchange figure sits within the address-reuse category, so adding the two percentages would double-count part of the total. “Moving those coins to a fresh address ends this exposure,” the firm wrote, referring to coins exposed through reuse. Address reuse accounts for most Bitcoin exposure In its methodology, Glassnode separates structural exposure, where an output reveals a public key by design, from operational exposure caused by how wallets handle funds. Reusing an address after spending can leave new or remaining coins tied to a public k...