§9.6.

Relay Track Handling

A relay MUST include all Properties associated with a Track when sending any PUBLISH, SUBSCRIBE_OK, TRACK_STATUS_OK, or FETCH_OK, unless allowed by the property's specification (see Section 2.5).

This is one section of the MoQT specification, rendered per-section for quick reference and citation. The authoritative text is draft-ietf-moq-transport-19 at the IETF.