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 ZOLL Medical (Nasdaq: ZOLL) slumped more than 11% in early trading on heavy volume.

So what: No discernible news caused the downturn. Rather, it seems Big Money investors are choosing to dump their positions and shop elsewhere. More than 1.33 million shares changed hands -- a 264% increase from the average trading day.

Now what: Color me intrigued. Not only are the sales without context, but also the underlying business is showing positive inventory trends and trades for a noticeable discount to the long-term annual earnings growth rate analysts expect. Where do you stand on this stock? Would you buy at current levels? Please weigh in using the comments box below.

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