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 Pinnacle Foods, Inc. (NYSE: PF) surged 15% today after Hillshire Brands (NYSE:HSH.DL) agreed to acquire the convenience food company for $6.6 billion.

So what: The cash-and-stock deal -- $18 in cash and 0.50 shares of Hillshire Brands common shares -- values Pinnacle at $36.48 per share and represents a premium of about 20% to its closing price on Friday. Hillshire is making the move to expand its presence in the grocery store -- Pinnacle's brands include Duncan Hines, Mrs. Paul's frozen seafood, and Vlasic Pickles -- but judging by its own stock's 6% pullback today, Mr. Market isn't exactly pleased with the price being paid to do it.

Now what: The combined company will be the No. 3 player in the frozen foods space and is expected to generate about $6.6 billion in sales for 2014. "The acquisition creates a leading branded food company with enhanced scale, reach, and capabilities while providing margin expansion and strong EPS accretion," Hillshire President and CEO Sean Connolly said. "The new Hillshire Brands will have a strengthened position in frozen foods, new opportunities in the center store for our brands and in refrigerated for Pinnacle Foods' brands." So while Pinnacle's upside is pretty limited at this point, Hillshire's newly bolstered scale and more diversified portfolio might be worth looking into.

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