Do Investors Care if Steve Jobs is Healthy?

Steve Jobs of Apple, Inc., is one of the best known CEOs in the world, and some stock analysts have termed him “irreplaceable.” Using conventional event study methods, we test the magnitude of these announcements on Apple’s share price and its market capitalization. We focus upon nine “events” between 2004 and 2009 in which new information about Mr. Jobs’ health was flushed into the marketplace, on occasion by Apple itself, but more often by the commentary and speculations of media observers, stock analysts and bloggers. We find that the impact of these announcements upon Apple share prices is mixed, usually modest, and disappears over time. We conclude that Jobs’ health has an impact on Apple’s share price and market capitalization, but that impact is not always negative and not nearly as large as many observers apparently believe.