What is the correct description of a certificate of mailing?

The correct description of a certificate of mailing is a statement confirming that a document was mailed. This document serves as proof that a filing was executed and sent to the appropriate office, providing a date of mailing that can establish compliance with deadlines.

A certificate of mailing is particularly important in the context of trademark applications and registrations, as it enables applicants to have a reliable record that their documents were submitted, thereby mitigating issues related to timeliness and ensuring they are considered valid submissions.

The other descriptions do not accurately capture the function of a certificate of mailing. It is not related to document review, notifications about trademark expiration, or records of prior trademark applications, as those pertain to different aspects of the trademark registration process.