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 acute-care hospital operator Health Management Associates (UNKNOWN:HMA.DL) sank 11% today after larger rival Community Health Systems (NYSE:CYH) agreed to acquire it for $3.9 billion.

So what: The cash and stock deal values Health Management at $13.78 per share and represents an 8% discount to its closing price on Monday of $14.92. Investors had been bidding up HMA in recent weeks amid the sale rumors, but unfortunately for them, management wasn't exactly in a position to command a higher price given the ongoing federal investigation into its admission practices, as well as the declining trend of its fundamentals.

Now what: The combined company will be the largest for-profit hospital chain in the U.S. with 206 hospitals across 29 states.

"Our complementary markets and the ability to form networks in key states, along with the synergies that will be available to us, can create value for the shareholders of our companies, the communities we serve, our employees and medical staffs," said Community Health Chairman and CEO Wayne Smith.

So, while HMA's upside is limited at this point, Community Health's newly bolstered scale 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.