Howard Atkins, Wells Fargo’s chief financial officer and SEVP, unexpectedly announced his retirement after the close on Tuesday, citing personal reasons.  On Wednesday, the bank lost $5 billion in market value, dropping Wells Fargo from its top spot as the largest U.S. bank by market value - a distinction it had held only since December 2010. 

Mr. Atkins, 60, will immediately begin an unpaid leave of absence.  His retirement will not become official until August.  CAO Timothy Sloan will replace Mr. Atkins;  Mr. Sloan’s former duties will shift to Patricia Callahan, who heads the Office of Transition.

Mr. Atkins joined Wells Fargo 10 years ago from the New York Life Insurance Company, where he served as CFO.  He previously had been CFO at the Midlantic Corporation, and had spent 17 years at Chase Manhattan Bank. 

    Market Shock.   Mr. Atkins's abrupt departure is likely to ignite plenty of speculation and probably will hurt the stock in the near term, according to a Sandler O'Neill analyst.  First, given that Mr. Atkins is only in his late-50s, a CFO transition was not expected for several more years.  It's understood he was well-respected among investors, and Wells Fargo's financial performance speaks for itself.  Second, Wells Fargo's last major management change - Dick Kovacevich to John Stumpf as chief executive officer - was well-telegraphed, measured, and took place over a period of time. This one is obviously different.  Third, the new CFO takes the title immediately, and Mr. Atkins' retirement will follow an unpaid leave of absence, which isn't typical. 

While Sandler O'Neill is glad the departure appears unrelated to Wells Fargo's financial condition or reporting, it's nonetheless shocking and some near-term pressure on WFC shares is understandable.  [should as the market digests such a big surprise.  [NYT Dealbook, 2/8; Barron's, 2/10]