Mo. Rev. Stat. § 407.1104: Caller identification service, telephone solicitor not to interfere with subscriber's use of service.

1. Any person or entity who makes a telephone solicitation to any residential subscriber in this state shall, at the beginning of such solicitation, state clearly the identity of the person or entity initiating the solicitation.

2. No person or entity who makes a telephone solicitation to a residential subscriber in this state shall knowingly use any method to block or otherwise circumvent any subscriber's use of a caller identification service.