Registration cancelled because registrant did not file an acceptable declaration under Section 8

When a trademark registration is "Cancelled - Section 8" because the registrant did not file an acceptable declaration under Section 8, it means that the trademark owner failed to provide necessary documentation to the United States Patent and Trademark Office (USPTO) demonstrating the continued use of the mark in commerce. Section 8 of the Trademark Act requires such a declaration to be filed at specific intervals to maintain the registration of the mark. If a trademark registration is cancelled for this reason you may be able to revive it with a Petition to revive, Petition to Director. If the trademark is cancelled, you may be able to use the trademark.