By Dan Moskowitz | May 4, 2015 â 10:21 AM EDT. As of the end of April 2015, Apple Inc. (AAPL) sported a market cap of $772.65 billion. The second most valuable company in the world is no longer Exxon Mobil Corp. (XOM) or Google Inc. (GOOGL), which have market caps of $364.53 billion and $383.15 billion, respectively. The second most valuable company is now Microsoft Corp. (MSFT), with a market cap of $394.03 billion.