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 Infinera Corp. (INFN -2.51%) jumped 12% Monday after a company executive purchased a significant number of shares.

So what: Specifically, an SEC filing Friday revealed Infinera CFO Brad Feller just spent over $206,000 to buy 25,000 shares at an average price of almost $8.25 per share.

Now what: As of yesterday's close, shares of Infinera had gradually drifted more than 12% lower since the company posted better-than-expected first quarter results last month. And that underperformance came despite at least one significant analyst upgrade since then. Feller's move, then, is viewed as a big vote of confidence and further negates concerns surrounding Infinera's previous slower-than-expected growth. To be sure, if Infinera can maintain its momentum and keep moving in the right direction, shares might well be able to continue rewarding patient investors from here.