Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of Bebe Stores (BEBE -2.63%) were taking a beating today, falling as much as 18% on reports that its CEO sold 140,980 shares of the stock, or all of his holdings.

So what: CEO Steve Birkhold's sale does not represent a significant percentage of the company's shares outstanding, but when the CEO of a troubled company sells his entire stake, investors are understandably worried. Birkhold was awarded those shares in February as part of option exercise, which may make the sale seem less suspicious considering it came just three months after he acquired them.

Now what: The insider selling brought the stock to a new 52-week low and comes just weeks after the women's fashion retailer posted yet another quarterly loss, seeing a quarterly shortfall of $0.27 in its third quarter. Analysts expect losses this year and next, as Bebe seems to be of many apparel retailers that have lost out to changing consumer tastes. Many investors have already lost faith in the company, and Birkhold's sale may indicate that he too doesn't see a turnaround happening anytime soon. After a series of losses and a comparable sales decline of 5.7% in the quarter, the future doesn't look promising for Bebe whether or not Birkhold is a shareholder.