Coinbase has identified 7 million BTC ($466 billion) that are vulnerable to quantum attacks, most of which belong to active users.
The report was published by the advisory board of the cryptocurrency exchange on quantum computing. Notably, it includes Stanford professor Dan Boneh and representatives from the Ethereum Foundation. Of these, 1.7 million BTC ($113 billion) are located in 20,000 outdated addresses that use P2PK. In these addresses, the public key itself is the address and is fully visible on the blockchain. This makes them vulnerable to future attacks.
It is assumed that these coins belong to Satoshi Nakamoto and owners who lost their keys a long time ago. However, the other 5 million BTC ($333 billion) are in cryptocurrency exchange wallets or belong to active users. The report does not specify particular cryptocurrency exchanges.