Which document can show the transfer of ownership of a trademark?

The transfer of ownership of a trademark is formally documented through an ownership transfer document, often referred to as an assignment. This document must clearly indicate that the previous owner has officially assigned their rights to the trademark to the new owner. A copy of this original ownership transfer document serves as a legal record that provides evidence of the change in ownership, making it the most definitive source to confirm that the transfer has taken place.

While a signed affidavit from the previous owner might indicate intent or confirm facts, it does not provide the formalized evidence of transfer necessary for legal purposes. Similarly, a notarized statement from a third party might serve as corroboration or testimony but lacks the specific legal weight of a signed assignment document. A certificate of registration, although proof of current ownership, does not inherently include evidence of the transfer unless it specifically notes the change in ownership following the assignment. Therefore, the correct answer, a copy of the original ownership transfer document, directly serves the purpose of showing the legal transfer of trademark rights.