Bitcoin holder recovered 5 BTC worth nearly $400,000 after 11 years, with Claude's help, after changing his wallet code while he was «stoned».
A Bitcoin holder regained access to a wallet holding $5 BTC, worth nearly $400,000, after more than eleven years of efforts, utilizing Anthropic's Claude to unlock an old backup and correct critical bug in code trials. According to X cprkrn, the problem began when he changed the password while under marijuana influence and then forgot it.
A few weeks before he managed to regain access, he found in an old notebook from his student years a list of words (seed phrase), i.e. the basic «key» His wallet. The addresses derived from these words matched those of a file on his computer, confirming that it was the wallet where the 5 BTCs were located. However, although this element brought him closer to the solution, the file itself remained encrypted and could not open it.
Early cryptocurrency wallets operated differently than modern ones. Mnemonic seed phrases created the HD key tree, but wallets often combined these keys with non-HD and imported keys. The latter are not recovered from the seed phrase and stored in a wallet file that requires a separate code. That was exactly what had happened, resulting in the specific keys remaining locked.
The holder had candidate codes and multiple wallet files on his computer and tried to do brute force in the locked file with the open source btcrecover tool, without success. The course changed when, from frustrated, he loaded his entire student computer data into Claude.
The model identified within the files hidden older copy of the wallet as of December 2019. At the same time, he identified a problem in setting, where the shared key and codes tested by btcrecover were not correctly combined. By correcting the error and using the earlier copy, before changing the password, Claude successfully performed the btcrecover and deciphered the private keys.
After recovering the keys, the user moved the five to earlier «lost» BTC in his current wallet. Evolution sealed a long-term effort that lasted over a decade and resulted in significant economic benefit, due to the great rise in Bitcoin's price in recent years.
The incident highlights the particularities of old wallets, where imported non-HD keys are not covered by the seed phrase and remain dependent on file codes. It also shows how an artificial intelligence tool can detect forgotten copies and correct parameters that prevent recovery, without any «Guesses» Magically, the right code.
In an earlier case, researchers took at least six months to open a Bitcoin wallet with a forgotten 20-character code, efort that paid about $1.6 million to BTC in 2024. Instead, another investor permanently lost access to an estimated $780 million, when a court decision in 2025 did not allow him to search a dump for the hard drive with 8,000 BTC.
