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 optical networking expert Infinera (Nasdaq: INFN) found a ray of light today, jumping as much as 11.6% on above-average volume on a generally gloomy market day.

So what: Over the weekend, SEC filings showed that Chief Marketing Officer David Welch had made a large open-market purchase of Infinera shares. Assuming he knows more about the company's potential future than we outsiders do, that's a very positive signal for the stock.

Now what: Infinera hasn't exactly been a market darling lately and still trades down by more than 10% over the past three months. Granted, sector peers such as Ciena (Nasdaq: CIEN) and Juniper Networks (Nasdaq: JNPR) have been doing even worse, but Welch is clearly bucking a trend here.

Mind you, Infinera has been burning cash for some time and sports negative operating margins alongside inventory bloat and a terrible cash conversion cycle. Welch seems to be betting on a recovery that his company hasn't shown many signs of achieving. The Motley Fool also owns shares of this five-star CAPS stock and has recommended it in three separate newsletters. Am I crying wolf here? Let me know using the comments box on this page.

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