On most days, CEOs can probably pretend that what is happening to the stock is beyond their control. But some days the stock is all about them.
Today, Microsoft's stock price is reacting to the news that Steve Ballmer is going to retire within the next 12 months. The market capitalization of MSFT is currently $285 billion. Yesterday it was about $270 billion. Microsoft's jump in stock price means that people think whoever gets picked to replace him will make Microsoft approximately $15 billion more valuable than it would have been if Ballmer remained at Microsoft indefinitely.
It could be worse, Microsoft is only up 5.8% at the moment. When Carly Fiorina left HP the shares rose 7.5%. And the leaving executives will own large amounts of the stock that is appreciating in value in response to their leaving. So this hit to their pride is balanced by a boost to their pocketbook and this is before whatever ridiculous severance they've negotiated for themselves is also taken into account.
Edit: It appears Ballmer doesn't have an additional retirement package, so he's going to have to content himself with the over $700 million he made on his stock holdings from the market's reaction to his impending retirement.
Disclosure: I talk about a lot of stocks. It should be assumed that I might own any mentioned in my blog posts either directly or indirectly and I'm not trying to get the reader to buy or sell anything since they should do their own research.