Data breach or cyberattack
🔧 ProductThe company suffers a significant security breach or operational outage.
Typical size
2-15%
Timeframe
Days to weeks; usually recovers within quarters
Evidence
3 logged events
Why it moves the price
Remediation costs, regulatory fines, customer churn and — for companies that sell trust or uptime — direct damage to the core product proposition.
What separates a good call from a naive one
Historically the market forgives breaches surprisingly quickly unless the company's product *is* security or reliability, in which case the damage is existential rather than cosmetic. Watch customer churn disclosures the following quarter.
Measured impact
Every logged event is measured against real closing prices: the move from the close before the event, compared with the S&P 500 over the same window.
Next day
-4.84%
- Median
- -1.76%
- Moved up
- 0% of 3
- vs S&P 500
- -4.83%
After 1 week
-14.37%
- Median
- -11.54%
- Moved up
- 0% of 3
- vs S&P 500
- -14.01%
After 1 month
-16.82%
- Median
- -14.55%
- Moved up
- 0% of 3
- vs S&P 500
- -15.91%
The logged evidence agrees with the textbook expectation. Based on 3 measured events.
The evidence (3)
Every row is a real event, measured against actual closing prices.
| Date | Stock | What happened | Next day | 1 week | 1 month | vs S&P |
|---|---|---|---|---|---|---|
| Jul 19, 2024 | CRWD | Faulty sensor update triggered a global Windows outage The rare case where the failure struck the company's own product promise — reliability. | -11.10% | -25.91% | -23.47% | -10.44% |
| Sep 12, 2023 | MGM | Cyberattack forced casino and hotel systems offline | -1.66% | -5.64% | -12.44% | -1.11% |
| Mar 22, 2022 | OKTA | Lapsus$ breach of a support contractor disclosed | -1.76% | -11.54% | -14.55% | -2.93% |
Measured from historical closing prices. Past reactions do not guarantee future ones. Not financial advice.