Managers of hedge funds spend most of their time evaluating stocks, so it's usually a good idea to keep an eye on what they're buying and selling.
If nothing else, trends among fund managers can move stocks in both directions. Apple Inc. (Nasdaq: AAPL) is a textbook case.
Billions of dollars in hedge fund money played a major role in pushing Apple stock to its highs last year, and contributed to its fall in the fourth quarter as many fund managers reversed their position.
Of course, many retail investors like to follow what the hedge funds are doing because their moves can often point to hot stocks or hot sectors.
Contrarian investors like to know where the big money is going so they can bet in the opposite direction.
The best way to follow the stock choices of hedge funds is to study their quarterly 13F filings with the Securities and Exchange Commission (SEC).
So here's a look at what has been moving in and out of hedge funds recently.