The Jobs effect: Apple again overtakes Exxon Mobil by Philip Elmer-DeWitt @FortuneMagazine August 26, 2011, 11:12 PM EDT E-mail Tweet Facebook Google Plus Linkedin Share icons When the market closed, it was once more the world’s most valuable public company When analysts warned that the greatest risk to Apple’s AAPL share price was Steve Jobs, they assumed that when he stepped down the stock would fall. So much for that theory. If the market action Thursday was ambiguous (the stock fell a bit, but less than the major indices), the message Friday was not. Apple rose $9.86 (2.64%) to close at $383.58. That made it, once again, the world’s most valuable company by market capitalization, ahead of Exxon Mobil XOM by $2.43 billion: Apple: $355.61 billion Exxon: $353.18 billion It also gave the 1 million restricted stock units that Tim Cook received Wednesday (along with his new title) a value — on paper — of a cool $383.58 million. Cook gets half those shares if he stays with Apple for another 5 years and the other half if he stays for 10. By then, of course, a million shares of Apple could be worth a whole lot more.