) -- David Sokol, the disgraced former protégé of

Berkshire Hathaway

( BRK-B) chief

Warren Buffett

, has continued buying up shares of

Middleburg Financial Corp.


, a tiny, Virginia-based bank, regulatory filings show.

Sokol was widely expected to succeed Buffett as CEO of Berkshire until it came to light in March that he bought shares of

Lubrizol Corp.

at the same time he was recommending the company to Buffett as a potential acquisition. Berkshire agreed to acquire Lubrizol in March for $9 billion.

David Sokol

Sokol has been steadily buying shares of Middleburg Financial since at least June 3, 2009, according to about 30 filings with the Securities and Exchange Commission. On that date, he owned about 700,000 shares. As of his latest filing on Monday, Sokol owned just under 1.48 million shares for the David L. Sokol Revocable Trust.

Shares of Middleburg Financial

got a big pop in March

following Sokol's resignation from Berkshire, reaching a high of $19 per share. That rise was fleeting, however, and the bank's shares closed Monday at $14.69.

Sokol could not be reached, and a call to Middleburg President and CEO Gary Shook, who is listed on Sokol's SEC filings as having power of attorney for Sokol, was not immediately returned Monday evening.


Written by Dan Freed in New York


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