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. On Monday, Silver Bay Realty Trust Corp (SBY)'s CEO, David N. Miller, made a $194,740 buy of SBY, purchasing 10,000 shares at a cost of $19.47 each. Silver Bay Realty Trust Corp is trading up about 0.5% on the day Thursday. Before this latest buy, Miller made one other buy in the past year, purchasing $231,250 shares at a cost of $18.50 a piece. And at Tri Continental Corporation (TY), there was insider buying on Monday, by Todd White who purchased 9,000 shares for a cost of $17.16 each, for a total investment of $154,438. Tri Continental Corporation is trading up about 0.2% on the day Thursday. White was up about 1.7% on the purchase at the high point of today's trading session, with TY trading as high as $17.45 in trading on Thursday. This is PassFail TV for Passfail.com, taking you behind the ticker on Thursday, March 7, 2013.