Now that Wells Fargo has completed its internal investigation into the fake account fiasco that resulted in millions of bogus accounts being opened in customers’ names, one federal banking regulator is admitting that it was aware of hundreds of related complaints nearly a decade ago, but failed to do anything to correct the problem.

The Office of the Comptroller of the Currency released a 15-page report [PDF] Wednesday finding that the agency failed to act on hundreds of whistleblower complaints related to the bank’s bad behavior.

According to the report, the OCC did not take timely and effective supervisory actions after Wells Fargo and the agency identified significant issues with complaint management and sales practices.

The report — issued by the comptroller’s office of enterprise governance supervision (EGS) — found that for seven years, between 2009 and 2016, the agency had ample opportunity to escalate supervisory action to resolve the bank’s sales issues, but none was taken.

The OCC notes that while issues with sales practices were identified in the bank’s audit committee report in 2005 and in the OCC’s own assessments since 2010, deficiencies in the agency’s supervision process led to untimely and ineffective supervision of complaints and whistleblower cases and of incentive programs.

For example, in 2010 the OCC had a meeting with former head of retail banking Carrie Tolstedt regarding 700 whistleblower complaints related to incentive plans. Tolstedt, who was nudged out the door for her failure to fix issues like the glut of unauthorized accounts, reportedly responded that the primary reason for the number of complaints was that the “culture encourages valid complaints.”

Despite this, the report found that OCC did not require the bank to provide an analysis of the risks and controls, or investigated the issues further.

Also in 2010, the EGS found that OCC examiners were concerned with Wells program — dubbed “Going for Gr-Eight” — that encouraged employees to sell eight products to households. However, there was no evidence that the agency assessed the program.

“Despite ongoing red flags from both OCC and Wells Fargo internal whistleblower cases as well as internal ethics line complaints regarding sales integrity violations and gaming sales incentives programs, EGS found no evidence that supervisory activities included in-depth review and testing of monitoring systems and controls over this area, at least from 2011 through 2014,” the report states.

The EGS concludes the report with several recommendations or “lessons learned” that the OCC should take into consideration going forward.

“Wells Fargo supervision since 2010 provides meaningful lessons learned about the importance of comprehensive complaint and whistleblower analysis and follow-up,” the report states.

For example, the EGS suggests that OCC implement a process to ensure periodic and comprehensive analyst of complaints and whistleblower cases, which should include testing, analysis of root causes, and appropriate follow-up.

The OCC should also develop an enterprise-wide whistleblower process and update external-facing interfaces on how to communication information to the agency.

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