The Office of the Comptroller of the Currency, the lead regulator for national banks, stripped the examiner, Bradley Linskens, of his supervisory powers within the last two weeks, said three sources, who were not authorized to discuss the matter publicly.
Linskens did not immediately respond to requests for comment. OCC spokesman Bryan Hubbard declined to comment.
Wells Fargo's board is expected to release a report on Monday detailing what went wrong at the fourth-largest U.S. bank, according to sources familiar with the matter. The bank and its board both declined to comment.
In September, Wells Fargo reached a $190 million settlement with the OCC and other regulators over its opening millions of accounts in customers' names without their permission. At the time, the bank said as many as 2 million accounts were affected, but has since said the number might be larger.
The report is the result of a seven-month investigation by Wells Fargo's board of directors into how and why the sales abuses happened. Thousands of employees were dismissed over the matter, and several have publicly said they opened the fake accounts to hit aggressive sales targets set by managers.
Wells Fargo now faces probes from other government agencies including the Department of Justice, which is investigating whether any laws were broken.
Linskens was responsible for day-to-day supervision of Wells Fargo and managed a staff of more than 60 people, according to past notices from the OCC. He joined the OCC in 1993 and earliest oversight of Wells Fargo began in 2006.
In 2016, Linskens was honored with the title "senior national bank examiner" and received accolades in a news release from Comptroller Thomas Curry, who runs the OCC.
In September, Curry ordered an internal review of how the OCC handled the Wells Fargo matter and whether the agency has "gaps in our supervision."
That review is drawing to a close, said an OCC official.
(Reporting by Patrick Rucker; Editing by Lauren Tara LaCapra and Lisa Shumaker)
By Patrick Rucker