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 packaging and paper products company Boise (UNKNOWN:BZ.DL) soared 26% today after larger rival Packaging Corp. of America (NYSE:PKG) agreed to acquire it for $1.27 billion.

So what: The transaction values Boise at $12.55 per share and represents a juicy 26% premium to its closing price on Friday. Packaging Corp. is making the move to increase its container board capacity in order to support growth, and judging by its own stock's 7% jump today, Wall Street is pleased with the price management is paying to do it.

Now what: The deal -- which is expected to close in the fourth quarter -- will boost Packaging Corp.'s containerboard capacity from 2.6 million tons to 3.7 million tons and should increase its corrugated products volume by roughly 30%."The acquisition is an excellent fit, both geographically and strategically, with unique and substantial synergies," said Packaging Corp. Chairman  Paul Stecko. "The combined company is expected to generate strong financial results and strong cash flow which will be used to pay down debt as well as to continue to return value to our shareholders." So while Boise is likely all popped out at this point, Packaging Corp.'s newly bolstered capacity and growth prospects might be worth looking into. 

Fool contributor Brian Pacampara has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.