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 Finisar (Nasdaq: FNSR) fell nearly 14% in early trading and closed off 12.6%. The optical-networking specialist reported mixed fiscal second-quarter results and a disappointing Q3 outlook.

So what: Finisar earned $0.23 a share of Non-GAAP profit on $241.5 million in revenue in Q2. Analysts were expecting $0.22 and $242.2 million, respectively, according to data compiled by Yahoo! Finance.

Now what: Finisar wasn't the only loser among optical networkers. Investors sold shares of Oclaro (Nasdaq: OCLR) and NeoPhotonics (Nasdaq: NPTN), too -- both stocks were off more than 8%. Do you believe the drops were deserved? Or are you buying Finisar and its peers at current prices? Please weigh in using the comments box below.

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