Complex sentence: In February 2015, Apple's value exceeded $700 billion, making it the most valuable U.S. company by far ad if Wayne kept his 10% stock until then, it would have been worth tens of billions.
Split into simpler sentences: In February 2015, Apple's value exceeded $700 billion, making it the most valuable U.S. company by far. Had Wayne kept his 10% stock until then, it would have been worth tens of billions.