Bargain hunters are wise to pay careful attention to insider buying, because although there are many various reasons for an insider to sell a stock, presumably the only reason they would use their hard-earned cash to make a purchase, is that they expect to make money. Today we look at two noteworthy recent insider buys.

At Arch Capital Group, a filing with the SEC revealed that on Monday, CEO Marc Grandisson purchased 23,500 shares of ACGL, at a cost of $24.50 each, for a total investment of $575,750. So far Grandisson is in the green, up about 12.2% on their buy based on today's trading high of $27.49. Arch Capital Group is trading up about 3% on the day Thursday.

And also on Monday, EVP Richard Lampen purchased $271,250 worth of Vector Group, purchasing 25,000 shares at a cost of $10.85 a piece. This buy marks the first one filed by Lampen in the past year. Vector Group is trading up about 1% on the day Thursday.