Warren Buffett, chairman of Berkshire Hathaway Inc., at an annual shareholder meeting weekend in Omaha, Nebraska, in 2009. (ANDREW HARRER/BLOOMBERG NEWS)

But such news is making repeat front-page appearances for more reasons than Buffett’s legendary status as an investing superstar. For one, Buffett’s squeaky-clean image running what has been called the moral bastion of American capitalism—he is famous for carefully vetting his managers with exacting ethical standards and for saying “it takes 20 years to build a reputation and five minutes to ruin it”—is now facing a troublesome controversy. That’s leading to more scrutiny than there would have been at companies less affiliated with leadership wisdom.

Here’s what happened: Sokol bought stock for his personal portfolio in a chemicals company called Lubrizol and then shortly thereafter pitched the company to his boss, telling Buffett in a phone call that he owned the stock. Buffett initially rejected the suggestion, but later acquired it. That triggered a $3 million gain for Sokol, the Wall Street Journal reports, an event Berkshire Hathaway did not disclose until after the sale, which could prompt the SEC to investigate. Buffett and Sokol both say they did nothing unlawful, but corporate governance experts say Buffett should have asked more questions or even raised the issue to lawyers or the board when Sokol first revealed his holdings.

The biggest reason Sokol’s departure is getting so much attention, however, is that it now leaves in doubt who will have the difficult job of stepping in for Warren Buffett. Buffett’s lionized status as an investing and management guru meant a nearly impossible task, even before these latest events occurred. Now, the pressure and spotlight on Buffett’s successor will be even greater.

Buffett has acknowledged the enormous challenge of filling his shoes already, suggesting that his current role would be split into a chief executive that runs the operating companies and at least one chief investment officer who manages the portfolio, maybe more. That’s a good first step toward dampening the expectations on Buffett’s successor, a critical step given how large his shoes are to fill.

But Sokol’s departure won’t make that transition any easier. For one, whoever is picked will now inevitably be seen as a second choice, which could leave some investors with less confidence. Scrutiny will be even higher not only on the chosen one’s performance, but on any potential lapse in his ethics (all the likely candidates are men).

CEO transitions are nearly always a challenging process. One that involves following a superstar as legendary as Warren Buffett can be downright formidable. Add an environment of heightened scrutiny, and the next CEO of Berkshire Hathaway has a nearly Herculean task on his hands. Good thing Buffett says he’s still tap dancing to work.

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