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 paper and packaging specialist Smurfit-Stone Container (NYSE: SSCC) soared 28% in early Monday trading after rival Rock-Tenn (NYSE: RKT) agreed to purchase it for $3.5 billion in cash and stock.

So what: Rock-Tenn's offer values Smurfit shares at about $35 per share, representing a 27% premium to Smurfit's closing price Friday. The deal comes just seven months after Smurfit emerged from bankruptcy with a substantially cleaner balance sheet.

Now what: For those of us not lucky enough to have caught Smurfit's surge, Rock-Tenn might be worth looking into. The acquisition, which is still pending regulatory and shareholder approval, should triple Rock-Tenn's annual top-line to roughly $9 billion. Rock-Tenn, along with rival International Paper (NYSE: IP), are also up nicely on the news, so Mr. Market seems to be quite happy with all the consolidation going on in the space.

Interested in more info on Smurfit-Stone? Add it to your watchlist.

Fool contributor Brian Pacampara owns no position in any of the companies mentioned. Try any of our Foolish newsletter services free for 30 days.

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