TORONTO - Manulife Securities expects to pay $11.7 million in compensation to clients who were inadvertently charged excessive investment fees as part of a no-contest settlement agreement with the Ontario securities regulator approved Thursday.

The Ontario Securities Commission says the payment includes opportunity costs on the overpaid fees. Manulife (MFC.TO) will also pay $520,000 to the commission to help it advance its mandate of protecting investors and cover costs related to the investigation.

The OSC was notified by Manulife in June 2015 after the financial institution discovered "inadequacies" in its payment systems that led to certain clients directly or indirectly being billed excess fees.

Nearly 5,500 clients were charged extraneous fees from 2005 to 2016, which had gone undetected by Manulife Securities Inc. and Manulife Securities Investment Services Inc.

Since then, the OSC says Manulife has taken "corrective action" and has implemented additional controls and monitoring systems to prevent it from happening again.

The regulator says it "found no evidence of dishonest conduct" by the company. Manulife neither admitted nor denied the accuracy the results of the OSC's investigation.