Learn the stock market › Why does a stock move? › Lesson 9 of 9
When a stock moves without news
How often it happens
Since Mar 25, 2026 we hold a saved review of 83 moves of at least 4% among Stockholm's biggest companies. In 26 of them the review says outright that no company news explains the move. That is 31%. Here are the latest.
| Company | Day | Move |
|---|---|---|
| Boliden | Oct 22, 2026 | −6.0% |
| Addtech | Oct 7, 2026 | −7.6% |
| AstraZeneca | Aug 3, 2026 | −9.4% |
| Essity | Jul 17, 2026 | +4.1% |
That is a floor. Sometimes the review mentions a piece of news that merely came the same day.
Why the price moves anyway
The whole market or sector moved. The company needs no reason of its own. See the lesson on the market and the one on sectors.
Someone large makes a large trade. A fund selling a lot in a short time can push the price down with nothing having happened at the company.
The news is not visible. Buyers can react to what no headline shows: a changed view of the sector, or research only a few have read.
Buyers pull in buyers. A rising price attracts more buyers, and a fall makes more people sell. The move can then outgrow anything at the company.
Why to be careful with explanations
After any large move, something can be found that fits. That does not make it the cause. Sometimes the most honest answer is that nobody knows.
The same goes for what happens after large falls: it can be measured, but not known ahead of time.
Test yourself
A stock falls 7% with no company news. What can you say for certain?
A real example: Why did Boliden move?