WINDERMERE, Fla. (Stockpickr) -- Corporate insiders sell their own companies' stock for a variety of reasons. They might need the cash for a big personal purchase such as a house or an expensive luxury car. Sometimes they sell as part of a planned selling program that they have put in place for diversification purposes, which allows them to sell stock in stages instead of selling all at one price. Other times they sell because they think their stock has reached a valuation where the upside is limited. Some even dump their own stock because they have inside knowledge on their sector and they might think that a slowdown is coming.But they only buy their own shares for one reason: They think the stock is a bargain and has tremendous upside. The key word in that last statement is "think." Just because a corporate insider thinks his or her stock is going to go up, that doesn't guarantee that it will happen. Insiders can have all the conviction in the world that their stock is a bargain, but if the market doesn't agree with them, it could end up going nowhere. Related: 5 Dividend Stocks Rewarding Shareholders At the end of the day, its large institutional money managers running huge mutual funds and hedge funds that drive stock prices, not insiders. That said, many of these savvy stock operators will follow insider buying activity when they agree with the insider that the stock is undervalued and has upside potential. Recently, a number of companies' corporate insiders have bought large amounts of stock. These insiders are finding some value in the market, which warrants a closer look at these stocks. Here's a look at a number of companies whose insiders have been loading up on their own stock recently per SEC filings.
Nasdaq OMX Group
People's United Financial
Twitter and become a fan on Facebook.