Every big exchange hack, and what BTC did next

Mt. Gox, Bitfinex, Bybit: what bitcoin's price did a day, a month and a year after each big exchange hack, plus some plain self-custody habits. Past hacks aren't a forecast

Disclosure: we make Hold My Bitcoin and Daily Edge (Overfit Labs). Links to both are at the end. Not investment advice.

Binance says about $6.3B was taken in a breach on Oct 30, and about $3B of it has been frozen. BTC dropped about 3-4% to about $76K, a six-week low (CoinDesk, CNBC, Reuters). That's all we'll say about this one, since it's still unfolding.

It made me go back and look at the other big exchange hacks and what bitcoin's price did afterwards. Here are three.

Mt. Gox, Feb 2014#

Withdrawals halted Feb 7. BTC fell from about $700 to about $540.
Bankruptcy on Feb 28, with 850K BTC missing.
About $499 a month later. About $255 a year later.

Source: BBC https://www.bbc.com/news/technology-26118002 (bankruptcy: Reuters)

Bitfinex, Aug 2, 2016#

119,756 BTC (about $72M at the time) stolen.
BTC fell about 20% in a day, from $607 to about $480.
About $577 a month later. About $2,690 a year later.

Source: CoinDesk https://www.coindesk.com/markets/2016/08/02/bitcoin-drops-nearly-20-as-exchange-hack-amplifies-price-decline

Bybit, Feb 21, 2025#

About $1.5B in ETH stolen.
BTC fell about 2.1% that day, to about $96K.
About $84K a month later. About $68K a year later.

Source: CoinDesk https://www.coindesk.com/markets/2025/02/21/bitcoin-ether-slumps-as-crypto-prices-crumble-on-report-of-massive-usd1-4b-bybit-security-incident

1-month and 1-year prices are Coin Metrics daily closes.

So what does that tell us?#

Not much you can trade on. The outcomes were mixed. Only Bitfinex recovered fast. A year after Mt. Gox and a year after Bybit, the price was lower than right after the hack.

Past hacks aren't a forecast; other things were going on each time. Not investment advice.

Habits that help no matter what the price does#

General stuff, not a recommendation to buy or sell anything:

Coins on an exchange are an IOU from that exchange. Know how much you keep there and why.
If you hold your own keys, write the seed phrase down on paper or metal and keep it offline. Never type it into a website, a chat or a "support" form.
Do a small test withdrawal first, then send the rest.
Turn on app-based 2FA or a hardware key on exchange accounts, and use address whitelisting if the exchange has it.
Make sure someone you trust knows how to find your backup if something happens to you.
When there's news like this, scammers send fake "verify your account" emails. Go to the site directly instead of clicking links.

Disclosure and links#

We make Hold My Bitcoin and Daily Edge, Overfit Labs. Both are free to use.

Every time bitcoin was declared dead, and how each one aged: https://holdmybitcoin.com/bitcoin-is-dead/?utm_source=nostr&utm_medium=social&utm_campaign=binance_hack&utm_content=longform_hacks
What exchanges actually charge (Coinbase, Kraken, Gemini, Binance.US): https://getdailyedge.com/daily-edge-pro/app/guides/crypto-exchange-fees-compared.html?utm_source=nostr&utm_medium=social&utm_campaign=binance_hack&utm_content=longform_hacks