Binance’s $6.3 billion “security incident” (see today’s news report) raises a narrow question that has a data answer: when a large exchange is hacked or halts withdrawals, what has bitcoin tended to do next? Bitcoin Mastery computed it from Yahoo Finance’s BTC-USD daily closes for eight events since 2016. The honest summary is that the first day has usually been negative and the following week has usually been worse, but eight events is a small and uneven sample, and two of the eight went the other way.
The method and the events
We took eight exchange events: the hacks of Bitfinex (2 August 2016), Coincheck (26 January 2018), Binance (7 May 2019, a smaller theft of about 7,000 bitcoin), KuCoin (25 September 2020), Crypto.com (17 January 2022), WazirX (18 July 2024) and Bybit (21 February 2025), plus the FTX withdrawal halt (8 November 2022), which was a failure rather than a hack. For each we measured the percentage change in the Yahoo daily close from the close before the event day to the close on the event day (day 0), and on days 1, 3, 7, 14 and 30 after it. We then compared with every possible window of the same length since 17 September 2014 (4,400 or more windows). The event list is ours, chosen from memory of well-known incidents after the fact, and the dates are the commonly reported ones; we did not re-verify each in this run. A different list would give different numbers.
| Event (day 0) | Day 0 | Day 1 | Day 3 | Day 7 | Day 14 | Day 30 |
|---|---|---|---|---|---|---|
| Bitfinex, 2 Aug 2016 | −9.70% | −6.58% | −5.15% | −3.05% | −4.76% | −5.60% |
| Coincheck, 26 Jan 2018 | −0.78% | +1.61% | +0.33% | −21.57% | −22.40% | −14.16% |
| Binance (7k BTC), 7 May 2019 | +1.44% | +4.10% | +11.00% | +39.11% | +38.57% | +36.11% |
| KuCoin, 25 Sep 2020 | −0.63% | −0.09% | −0.47% | −1.71% | +2.83% | +21.11% |
| Crypto.com, 17 Jan 2022 | −2.00% | −1.71% | −5.64% | −14.98% | −10.74% | +1.97% |
| FTX halt, 8 Nov 2022 | −10.01% | −22.92% | −17.32% | −18.05% | −21.42% | −16.35% |
| WazirX, 18 Jul 2024 | −0.23% | +4.04% | +6.29% | +2.59% | +1.93% | −7.24% |
| Bybit, 21 Feb 2025 | −2.25% | −1.79% | −7.03% | −14.20% | −11.79% | −12.49% |
| Mean of 8 | −3.02% | −2.92% | −2.25% | −3.98% | −3.47% | +0.42% |
| Median of 8 | −1.39% | −0.90% | −2.81% | −8.62% | −7.75% | −6.42% |
| Events up (of 8) | 1 | 3 | 3 | 2 | 3 | 3 |
| All windows since 2014: mean | +0.18% | +0.35% | +0.71% | +1.45% | +2.80% | +6.16% |
| All windows: median | +0.10% | +0.27% | +0.37% | +0.71% | +1.34% | +2.99% |
What the numbers say — and do not say
On day 0 the mean was −3.02% and only one of eight events was positive, against a base rate of 52.3% of days being up and a mean of +0.18%. In a permutation test that draws 8 random windows from the full history 20,000 times, a mean this low or lower on day 0 came up in 0.8% of draws; for day 1 it was 2.8%, for day 7 (mean −3.98%) 6.0%, and for day 30 (mean +0.42%) 24.6%. In plain terms: the first-day weakness is unlikely to be chance alone even with eight observations, the week-later weakness is borderline, and by day 30 there is no distinguishable effect. Half the events (Coincheck, Crypto.com, FTX and Bybit) were down 10% or more at day 7, compared with 9.4% of all seven-day windows since 2014.
Three cautions matter more than the p-values. First, the events are not independent of the market around them: FTX’s halt and Bybit’s hack arrived in falling markets, and the 2019 Binance theft arrived at the start of a rally that lifted bitcoin about 39% in the following week, which has nothing to do with the hack. Second, the size of the event matters; Binance 2019 and KuCoin were small relative to the market, while Bitfinex 2016 and FTX were existential for their users. Third, day 0 includes whatever else happened that day, so it overstates the hack’s own share. The median, which ignores the 2019 outlier, is the more conservative summary at every horizon except day 30, where the mean and the median disagree on sign.
Where Binance stands so far
Using Coinbase’s UTC-day data (not Yahoo’s, so small differences are possible), the Binance event began at 20:20–20:24 UTC on Thursday 29 October. Bitcoin closed that UTC day at $77,780.33 against the previous close of $81,249.31, a fall of 4.27% on day 0. That is worse than six of the eight historical day-0 moves; only Bitfinex (−9.70%) and FTX (−10.01%) were worse. The first 24 hours after the event started are not complete: at 07:05 UTC on Friday bitcoin was at about $78,390, 3.5% below Wednesday’s close, after a low of $76,301.02 at 02:00 UTC. We will not forecast day 7. The Bybit analogy, a hot-wallet theft followed by a prompt reimbursement pledge, saw bitcoin down 14.2% a week later in a market that was already weakening; Binance has also pledged to cover all user losses from its SAFU fund and company funds (Forbes), but the current backdrop includes a Federal Reserve that held at 3.75%–4% with two dissents for a hike (our report), so the comparison is loose.
The video above was published on 14 October 2026, before the Binance incident, and discusses exchange hacks in general; it is background and not a source for any figure here.
Limits of the study
- Eight events, chosen after the fact from memory; the list omits smaller and larger incidents we did not think of and the earliest big failure, Mt. Gox in 2014, which falls before the start of our price series.
- Yahoo’s daily close is the 00:00 UTC price; events that unfolded late in a UTC day (such as Binance, at about 20:20 UTC) leave only a few hours inside day 0.
- Different kinds of events are pooled: thefts that the exchange covered, a failure that wiped out customers, and one outage-type halt. They need not have the same effect.
- The permutation test treats windows as exchangeable, which they are not in a market with trends and volatility clusters; the p-values are rough guides, not proof.
- The study describes the past and is not a forecast; it does not say what bitcoin will do after Binance.
Sources: Yahoo Finance BTC-USD daily data (own calculation, 17 September 2014 to 30 October 2026); Coinbase Exchange candles for Binance day 0; Forbes and FinanceFeeds for the Binance facts and the Bybit comparison. Related: CFTC chair on preventing another FTX.
Method: bitcoin and ether prices, highs, lows and closes are Coinbase Exchange candles (UTC hour or UTC day) pulled by Bitcoin Mastery at about 07:05 UTC on Friday 30 October 2026; the 30 October candle is still open at that time, so any daily close quoted is the 29 October close (77,780.33) unless stated. Third-party figures are attributed to their source; incident details were still changing at pull time. The Yahoo series for 30 October is a partial day and is excluded from all statistics.
Disclaimer: This article is for informational purposes only and does not constitute investment advice. Bitcoin and other cryptocurrencies are volatile and you can lose some or all of the money you put in. Nothing here is a recommendation to buy, sell or hold bitcoin, any exchange-traded fund, any listed security or any other asset, and the technical levels, probabilities and scenarios discussed are descriptions of published data, not forecasts. Do your own research and consult a licensed financial advisor before making investment decisions.