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 AMCOL International Corporation (UNKNOWN:ACO.DL) jumped 12% today after the company agreed to be acquired.

So what: Imerys S.A. is acquiring AMCOL for $41 per share in cash in a transaction that's valued at about $1.6 billion. AMCOL will merge with a subsidiary of Imerys, and AMCOL will actually be the surviving company. 

Now what: Shares are now trading higher than the $41 offer price, which indicates that investors think the offer will eventually go up. Usually, buyouts take place at more than a 12% premium, so I could see shareholders demanding more money. With that said, there's a risk that the deal will go off as planned, and cashing out some shares at the higher price would be a good move today.