Apple back to the top as the most valuable company by market capitalization. Apple (APPL) $ 417.B, ExxonMobil (XOM) $  414.0B. Others Google (GOOG) $185B, Amazon (AMZN) $ 84.35, IBM (IBM) $ 221.2B), Microsoft (MSFT) $ 247.2B,Yahoo (YHOO) $ 29.92B, Hewlett Packard (HPQ) $ 56.08B, Intel (INTC) $135.2B, Cisco (CSCO) $ 105.7B.