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 Brookdale Senior Living (NYSE: BKD) surged a whopping 20% this morning, after an acquisition in the industry sparked optimism about the company's true worth.

So what: This morning, health-care REIT Ventas (NYSE: VTR) said that it is purchasing real estate properties from Altria Senior Living Group for $1.5 billion in cash and stock. When you couple Brookdale's position as the nation's largest owner of senior communities with its $2 billion-ish market cap, it's no surprise that investors are bidding up the price on today's news.

Now what: Twenty percent pops are rare, so I'd consider taking at least some dough off the table. Rivals such as Sunrise Senior Living (NYSE: SRZ), Emeritus (NYSE: ESC), and Capital Senior Living (NYSE: CSU) are also up big on the news, but not nearly as much as Brookdale is. So if the Ventas purchase has you particularly bullish on senior homes, spreading your bet across the sector might be the most prudent thing to do.