Which of the following methods is NOT used for contacting the Office of the Commissioner for Trademarks?

The method that is not typically used for contacting the Office of the Commissioner for Trademarks is in-person meetings. The USPTO primarily encourages communication through more formal channels such as phone contact, written inquiries via mail, and email communication. This approach allows for standardized record-keeping and more efficient handling of inquiries. While in-person interactions can be valuable in certain contexts, they are not a recognized or routine method for engaging with the office, which relies on structured communication methods to manage the high volume of inquiries and maintain consistency in responses.

In general, the USPTO's processes are designed to streamline trademark-related communications, making it easier for applicants and registrants to receive timely responses to their questions and concerns through the available official channels.