Are there restrictions on communicating with unregistered, suspended, or excluded attorneys regarding patent applications?

Yes, there are strict restrictions on communicating with unregistered, suspended, or excluded attorneys regarding patent applications. The MPEP clearly states:

Office employees are forbidden from holding either oral or written communication with an unregistered, suspended or excluded attorney or agent regarding an application unless it is one in which said attorney or agent is the applicant.

This rule helps maintain the integrity of the patent application process and ensures that only qualified, registered practitioners are involved in patent-related communications with the USPTO.