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 biocides company Arch Chemicals (NYSE: ARJ) jumped 11% today when it announced it was being acquired by Lonza Group.

So what: The European-based Lonza will pay $47.20 per share for Arch Chemicals in a deal that will total $1.4 billion, including debt. Adding Arch will help reduce Lonza's reliance on making products for drugmakers and increase sales in growing markets such as China, India, and Brazil.

Now what: There are some interesting side notes surrounding the deal. Volume was through the roof Friday and shares were up 11% in the lead-up to a deal that no one was supposed to know about. Then today, at least two law firms announced they were opening investigations into whether Arch directors acted in the best intentions for shareholders by accepting the Lonza offer. Something strange went on Friday, but for now investors aren't getting a very good premium to hang on to shares, so selling today may be the best option unless you think a better deal is coming.

Interested in more info on Arch Chemicals? Add it to your watchlist.

Fool contributor Travis Hoium does not have a position in any company mentioned. You can follow Travis on Twitter at @FlushDrawFool, check out his personal stock holdings or follow his CAPS picks at TMFFlushDraw.

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