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 Corrections Corporation of America (NYSE: CXW) jumped 12.5% in early trading after an activist investor announced a position. Shares have settled at a 5% gain as the day went on.

So what: Corvex Management joins Marcato Capital Management as two hedge funds with significant positions in the company. The two companies are trying to convince management to convert the company to a real estate investment trust for tax purposes.

Now what: A REIT has tax advantages over a traditional corporation, and the two funds think the structure could "significantly lower cost of equity capital." The move could be good for shareholders, but a final determination has yet to be made. The bump that occurred today may not last in the short-term so I wouldn't be afraid to wait out traders who jumped into the stock today if you're looking to buy.

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