On October 14, Bank of America reported third-quarter results that fell short of expectations, sending its shares down about 8%, which could mark the largest post-earnings single-day decline since 2010.

Previously, the U.S. Treasury fined the bank $1.2 billion over deficiencies in anti-money laundering and other compliance procedures, and the company said the penalty reduced third-quarter earnings per share by $0.17.

However, even excluding the impact of the fine, Bank of America's quarterly revenue and net profit still came in below market expectations, triggering further investor concerns about the bank's profitability and the cost of compliance remediation.

$1.2 billion fine hits earnings, and results still miss expectations even after excluding its impact

On October 13, the U.S. Treasury announced a $1.2 billion fine against Bank of America related to deficiencies in anti-money laundering and other compliance procedures.

Bank of America said the fine reduced third-quarter earnings per share by $0.17.

But market concerns did not stop at a one-time penalty, because even after excluding the related impact, the bank's revenue and net profit still failed to meet analyst expectations.

After the earnings release, Bank of America shares fell about 8%, a decline that may set the largest single-day record for the stock following an earnings announcement since 2010.

JPMorgan questions remediation costs, bank management says it has already invested billions of dollars

On the earnings call, JPMorgan analyst Vivek Juneja questioned Bank of America's compliance costs.

He noted that Bank of America had previously said the related compliance spending was already included in ordinary operating costs, yet a large expense still appeared this time, surprising the market.

Juneja argued that this involves not only a short-term financial impact, but may also damage market trust in the bank's management.

Bank of America management responded that the related compliance expenses had already been incorporated into ordinary operating costs, that the company had been working with regulators over the past several quarters to advance remediation, and that it had invested billions of dollars to combat financial crime.

However, analysts still focused on whether the penalty means the related compliance issues have not yet been fully resolved, and whether more remediation spending may arise in the future.

The main controversy sparked by these results has extended beyond the $1.2 billion fine itself to whether Bank of America can effectively control ongoing compliance costs and restore market confidence in its earnings outlook and management's execution capability.