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 Momenta Pharmaceuticals (NASDAQ:MNTA), a biotechnology company primarily engaged in the development of biosimilar and generic compounds, dipped as much as 13% after the company reported its first-quarter results before the opening bell.

So what: For the quarter, Momenta recorded $10.8 million in revenue comprised of $4.8 million in collaborative product revenue and $6 million in research and development compensation. This compares favorably with the $7.6 million reported in the year-ago period. The company's operating loss widened, however, to $27.6 million, or $0.53 per share, from $24.4 million in Q1 2013. By comparison, Wall Street forecasted just $9.4 million in revenue and a loss of $0.53 per share.

Now what: "So if the company met or topped estimates, why is it being clobbered?" you might be wondering. That primarily has to do with this commentary: "During the period the patent [for Teva Pharmaceutical's (NYSE:TEVA) Copaxone] is under review, we plan to adjusted our operating plans and to maintain our financial flexibility." A monstrous amount of Momenta's valuation has revolved around bringing a generic version of multiple sclerosis drug Copaxone to market. However, Teva appears to be doing everything in its power to prevent a generic version from reaching pharmacy shelves. With the patent case expected to be heard by the Supreme Court in the fourth quarter of this year, it means more waiting for Momenta shareholders and likely no profit potential until next year. Clearly, that isn't sitting well with shareholders today that had anticipated a mid-year generic Copaxone launch.

Still, Teva isn't going to be able to protect Copaxone from generic competition forever, and Momenta, along with a number of other generic drugmakers, looks poised to capitalize on an eventual generic introduction. I'd suggest that, if Momenta shares fall much further, they could actually become attractive and worthy of a deeper dive.

Sean Williams has no material interest in any companies mentioned in this article. You can follow him on CAPS under the screen name TMFUltraLong, track every pick he makes under the screen name TrackUltraLong, and check him out on Twitter, where he goes by the handle @TMFUltraLong.

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