Municipal securities brokers and dealers will face tougher telemarketing restrictions as of August 22, including a prohibition against hiding their phone numbers on consumers’ caller ID display screens, said the Municipal Securities Rule Making Board on Wednesday.

The board’s action follows the Securities and Exchange Commission’s approval of the guidelines.

Dealers will also be required to maintain “do not call” lists and will only be allowed to make calls between 8 a.m. and 9 p.m. in a consumer’s time zone.

Dealers that outsource telemarketing to a third party will be responsible for ensuring that the vendor adheres to the restrictions.

The SEC has mandated that self-regulatory organizations such as the MSRB must adopted rules to comply with Federal Trade Commission telemarketing restrictions against deceptive and abusive telemarketing practices.

The MSRB has not sanctioned any broker or dealer for telemarketing violations, at least in recent years.