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 aircraft leasing company AerCap Holdings N.V. (AER -0.63%) jumped over 30% today after the company announced an acquisition.

So what: AerCap is buying AIG's (AIG 1.70%) aircraft leasing arm, called International Lease Finance Corp., for $3 billion in cash and 97.56 million shares of new AerCap stock. At today's stock price, the deal is worth about $6.2 billion and will make AIG the largest shareholder with 46% of AerCap's stock.  

Now what: This deal was rumored last week and became a reality today with the help of cash financing lined up by AerCap this year. It makes the company the largest aircraft leasing company in the world with a huge backlog of Boeing and Airbus orders. AerCap CEO Aengus Kelly said that was "the jewel in the crown" of the deal.