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 Florida-based staffing company SFN Group (NYSE: SFN) were hitting the stratosphere today, gaining as much as 52% in intraday trading on heavy volume.

So what: Why such a massive gain? That's easy -- The Netherlands' Randstad is buying SFN Group for $770 million, or $14 per share. The offer is a 49% premium to SFN's trading price over the month ending July 19. The deal will double Randstad's presence in the U.S. and make it the third largest North American staffing firm.

Now what: The deal is a cash offer, so SFN investors may want to start thinking about where they'll redeploy their capital. Given the size of the premium of the offer and the fact that trading today hasn't breached the offer price, it doesn't seem like there's a strong case to stick around and expect a higher bid.

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