And already a second purchase of 39 MSEK. It’s not huge money, but they would hardly be shoveling more money into what is already their largest holding if it were seen as a burning platform.
On the other hand, you should never trust too much in the rationality of investors. 
It’s worth mentioning that Fredrik Wester himself also bought shares with some pocket change.
This isn’t a scientific study, but the WSJ compiled data on insider buys in the US from recent years. Insiders tend to buy shares during the dip (who doesn’t? :D).
But, on average, after a short bounce, many stocks continue to crawl thereafter.
Therefore, these shouldn’t be interpreted too over-positively because price developments are scattered like a shotgun blast.
An insider buy is thus like another person working at the company urinating in my pants in freezing weather. The momentary warmth can be followed by cold again.
Link to the paywalled news article: https://www.wsj.com/finance/stocks/is-it-really-a-good-sign-when-executives-buy-their-own-stock-we-ran-the-numbers-2655b232?mod=hp_lead_pos8