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 senior services provider Sunrise Senior Living (NYSE: SRZ) were looking peppy today as they jumped as much as 11% on heavier-than-average volume.

So what: On Friday, the stock was making a similar move after the company announced fourth-quarter earnings. As my fellow Fool Rich Smith pointed out, the solidly black bottom line was due largely to non-recurring factors, but it showed that the company is making progress nonetheless. Today's move could include some afterglow from Friday's jump, but it also likely has to do with Ventas' (NYSE: VTR) takeover of Nationwide Health Properties (NYSE: NHP). Sunrise has a close relationship with Ventas as a manager of a significant portion of the company's properties, and investors may be hoping that the deal will give Sunrise a shot at some of the Nationwide properties.

Now what: Investors who think the Nationwide deal will be a bonanza for Sunrise may want to temper their optimism a bit. Granted, the Nationwide deal is hardly bad news for Sunrise, and it may find itself with new opportunities from the deal. But Nationwide has a strong relationship with Brookdale Senior Living (NYSE: BKD), and given that Ventas has an ongoing relationship with Brookdale as well -- it manages roughly 20% of Ventas' properties -- massive changes don't seem that likely.

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