Antitrust ruling or regulatory action
⚖️ LegalA court or competition authority rules against the company, or moves to block a practice or deal.
Typical size
2-15%
Timeframe
Immediate, then years of appeals
Evidence
2 logged events
Why it moves the price
Directly threatens a revenue stream or a structural advantage. Remedies can force divestitures or ban lucrative arrangements.
What separates a good call from a naive one
Reactions are frequently smaller than headlines suggest, because remedies take years and appeals are likely. The severe move comes at the *remedy* stage, not the liability finding. A blocked merger hits the target far harder than the acquirer.
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
+2.35%
- Median
- +2.35%
- Moved up
- 50% of 2
- vs S&P 500
- +3.53%
After 1 week
+5.79%
- Median
- +5.79%
- Moved up
- 50% of 2
- vs S&P 500
- +5.00%
After 1 month
+5.15%
- Median
- +5.15%
- Moved up
- 50% of 2
- vs S&P 500
- +1.15%
No measured verdict yet — 2 events logged. Three or more are needed before the data says anything useful.
The evidence (2)
Every row is a real event, measured against actual closing prices.
| Date | Stock | What happened | Next day | 1 week | 1 month | vs S&P |
|---|---|---|---|---|---|---|
| Sep 3, 2025 | GOOGL | Remedies ruling landed far milder than investors feared The counter-example to the 2024 liability ruling: an antitrust decision the stock rose on, because the remedy left the business model intact. | +9.14% | +13.38% | +15.87% | +8.59% |
| Aug 5, 2024 | GOOGL | Federal judge rules Google holds an illegal monopoly in search Liability finding only; remedies were left to a later phase, which is why the reaction was smaller than headlines implied. | -4.45% | -1.79% | -5.58% | -1.53% |
Measured from historical closing prices. Past reactions do not guarantee future ones. Not financial advice.