WASHINGTON (Reuters) - The U.S. Securities and Exchange Commission (SEC) on Monday said more than two dozen investment advisers and broker-dealers agreed to settle charges that they failed to file a key form designed to inform retail investors. The SEC said it had settled charges against 21 investment advisers and 6 broker-dealers for failing to file or deliver customer relationship summaries to their retail investors. The paperwork is used to notify retail investors of conflicts of interest and other information that is significant for investors to decide whether to work with a financial firm. None of the firms filed or delivered the forms until being reminded twice by regulators, the SEC said in a statement here. “Registration with the SEC as an investment adviser or broker-dealer comes with mandated filing and disclosure obligations,” it said. The cases underscored the importance of “providing retail investors with information that is intended to help them understand their relationships with their securities industry professionals,” Gurbir S. Grewal, head of the SEC’s enforcement division, said in the statement. Our Standards: The Thomson Reuters Trust Principles.