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 Forest Laboratories, (NYSE: FRX) soared 30% today after generic-drug maker Actavis plc (NYSE:AGN) acquired the specialty pharmaceutical company for about $25 billion.

So what: The cash-and-stock deal -- $26.04 in cash and 0.3306 of an Actavis share -- values Forest at $89.48 per share and represents a premium of 25% to its Friday closing price. Actavis is making the move to expand its specialty drug portfolio, and judging by its own 7% pop today, Wall Street is pleased with the price management is paying to do it.

Now what: If completed, Actavis expects the deal to be immediately accretive with the combined company generating $15 billion in annual revenue. "With this strategic combination, we create an innovative new model in specialty pharmaceuticals leadership, with size and scale, a balanced offering of strong brands and generics, a focus on strategic, lower-risk drug development, and -- most important -- the ability to drive sustainable organic growth," said Actavis Chairman and CEO Paul Bisaro. So while Forest's upside is likely limited at this point, Actavis' newly bolstered portfolio might be worth looking into. 

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