David Sokol earned the trust of Warren Buffett, and was widely regarded as the most obvious successor to his fellow Nebraskan in one of the most exalted positions in American business.
But the hard-charging executive pulled out of the running for the top job at Buffett's Berkshire Hathaway Inc., his home for a decade, when he resigned from his job there on Wednesday.
Sokol's surprise departure came as Buffett revealed that Sokol had pitched chemical company Lubrizol Corp to him as an acquisition target barely a week after buying shares for his own account.
Sokol was formerly so trusted at Berkshire that in recent years he was the only official other than Buffett and Vice Chairman Charlie Munger regularly allowed to address the tens of thousands of shareholders attending the company's annual meeting in Omaha, Nebraska.
Sokol was chairman of Berkshire's MidAmerican Energy unit when Buffett installed him to turn around its ailing NetJets corporate jet company, a business where he had no experience.
Sokol was successful.
In his annual letter to shareholders this year, Buffett praised Sokol for engineering the turnaround at NetJets, which under prior leadership had racked up $1.9 billion of debt and regularly lost money. NetJets is now profitable.
A year earlier, Buffett called Sokol "an enormously talented builder and operator," and in 2009 he proclaimed that Sokol would run any business with which he was associated "in a first-class manner."
Sokol has also become a go-to person to help Buffett negotiate acquisitions and investments, including a 9.9 percent stake in Chinese automaker BYD Co. and this month's purchase of Lubrizol.
"He gets more done in a day than probably I get done in a week, and I'm not kidding," Buffett told Fortune magazine last year.
"If I had any knock against Buffett, (it) is how much he espoused his successor, how this was the right guy, how much he rallied the flag around him as his successor," said Matt McCormick, a portfolio manager at Cincinnati-based Bahl & Gaynor Investment Counsel. "And now this guy is gone."
In his press release announcing Sokol's departure, Buffett said he did not believe Sokol's purchases of Lubrizol stock were unlawful.
Sokol could not be reached for comment.
Sokol told Fox Business Network that he wants to run his own business and control his own schedule. He also said "there was no inside information" involved in his Lubrizol trades.
Sokol obtained a bachelor's degree in civil engineering from the University of Nebraska at Omaha in 1978 and holds an honorary doctorate from Bellevue University in that state.
The hockey, hunting, fishing, running and horseback riding enthusiast is also author of a business management book, "Pleased But Not Satisfied."
Berkshire did not release Sokol's March 28 letter of resignation, though Buffett said that Sokol mentioned a desire to pursue philanthropic efforts.
And while Sokol's departure is a loss for Berkshire, Buffett remains, and the company is believed to still have at least three potential successors for whenever the 80-year-old steps aside as chief executive.
"Sokol will be missed, but the bench is pretty deep," said Jerry Bruni, chief executive of J.V. Bruni and Co. in Colorado Springs, Colorado, which invests $450 million.
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