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 Gray Television (NYSE:GTN) jumped as much as 19% today after it announced a deal to buy 15 TV stations from Hoak Media and Parker Broadcasting.

So what: In a deal Gray made with Excalibur Broadcasting, the two companies will purchase 15 stations from the two sellers for $335 million. Gray will take ownership of 12 stations in the U.S. after selling four due to regulatory requirements. The stations will add to Gray's leading position in the central U.S., as CEO Hilton Howell said the "transactions will yield impressive synergies, many of which are unique to Gray given how well the stations' locations, operations and culture complement our own." The purchases give Gray a total of 123 stations in 39 markets, reaching more than 7% of U.S. TV households.

Now what: The transaction is expected to be completed in the first half of 2014. TV broadcasting stocks have soared this year as companies snatch up increasingly valuable spectrum, and the industry becomes further concentrated. Gray shares have jumped nearly 400% this year as the company expanded. Its strategy looks poised to pay off, as ownership of the No. 1 and No. 2 stations in a number of its markets should help it boost margins and increase its market power going forward.