The only way to know for sure why a fund manager sells the stock...

The only way to know for sure why a fund manager sells the stock is to ask the fund manager.

But to speculate...one possible reason could be that they reached an investment constraint that forced them to sell part of their holding.

Hypothetical example: a fund manager that bought enough MMX to make up 1% of his portfolio at $0.40.....the stock has now gone up more than 8x, meaning it would now represent more than 8% of his portfolio.

Most fundies have a restriction on how much they can hold in a single stock...and it is usually around 3-5%...often at the lower end of that range for small cap stocks.

So that is one possible answer to Joker's question. If anyone has a better suggestion let me know.