Coinbase’s Conor Grogan Flags $8.6B ‘Sleeping’ Bitcoin Wake-Up as Potential Historic Hack

Coinbase’s Conor Grogan flagged that US$8.6B in BTC moved last week from eight dormant wallets could mean a huge hack of 14-year-old keys.
A small Bitcoin Cash transaction before the BTC move hints the hacker or owner may have tested keys quietly, but other linked BCH wallets stayed untouched.
Arkham says all BTC came from one source, now split across new wallets, leaving it unclear if this was a planned shuffle or the biggest crypto theft ever.

Conor Grogan, Coinbase’s head of product, thinks there’s a real chance last week’s sudden US$8.6B (AU$13.1B) Bitcoin move could be a massive hack. Eight old wallets, untouched since 2011, sent out all their coins on Thursday, and no one knows why.

Grogan spotted a strange clue: one of the wallet owners sent a small Bitcoin Cash transaction just before the huge Bitcoin transfer. He says that might have been a quiet test to check if the old private key still worked. But what doesn’t add up is that other BCH wallets tied to the same stash stayed frozen.

Related: Bitcoin ETF Blitz: BlackRock’s IBIT Tops S&P 500 Giant in Fee Take

There is a possibility that the owner was testing the private key in a way that wouldn’t get noticed, as BCH isn’t monitored heavily by whale watching services. What makes me say this is the other BCH wallets have not been touched at all; why wouldn’t they also sweep these?

Conor Grogan, Coinbase’s head of product

Blockchain firm Arkham confirmed the coins all came from the same source, sat untouched for over 14 years, and were moved into eight new wallets where they remain. It’s still unclear if the owner is just reorganising or if someone got in and drained the stash.

A single entity moved $8.6 BILLION of BTC from 8 addresses in the past day.
All of the Bitcoin was moved into the original wallets on either 2nd April or 4th May 2011 and has been held for over 14 years.
Currently, the Bitcoin is sitting in 8 new addresses and has not been… pic.twitter.com/nm53tVRzLJ
— Arkham (@arkham) July 4, 2025