As the saying goes, there are many possible reasons for an insider to sell a stock, but only one reason to buy -- they expect to make money. So let's look at two noteworthy recent insider buys.

At Cooper Companies, a filing with the SEC revealed that on Wednesday, CEO Albert G. White III purchased 1,000 shares of COO, for a cost of $278.23 each, for a total investment of $278,230. Cooper Companies is trading up about 4.2% on the day Thursday. This buy marks the first one filed by White III in the past twelve months.

And at Raven Industries, there was insider buying on Wednesday, by Director Jason M. Andringa who purchased 3,000 shares for a cost of $20.17 each, for a total investment of $60,517. Before this latest buy, Andringa made one other buy in the past twelve months, purchasing $59,175 shares at a cost of $20.91 a piece. Raven Industries is trading down about 1.2% on the day Thursday.