The violations stem from a 2020 change where Vanguard lowered the minimum investment requirement for its institutional target date funds.

An investigation by the S.E.C. and several states found that the company had failed to notify investors of changes in the terms of some funds, leading to higher capital gains taxes.

Vanguard Group will pay $106.4 million to settle U.S. Securities and Exchange Commission charges alleging it failed to disclose important tax information about its popular target-date funds, resulting in hundreds of thousands of ordinary investors getting stuck with inflated tax bills.