"Return letter (notice of acceptance of trademark transfer application)": It means that the Trademark Office sends it to the agency through the post office, or the trademark registration applicant sends it by registered mail. If the agency or trademark registration applicant moves to another location, or there is no one to accept it, the post office will return the registered letter of the acceptance notice to the registration hall of the Trademark Office. Finally, the agency or trademark registration applicant will go to the trademark registration hall to receive the acceptance notice in person. Walk. To put it bluntly, it is the acceptance notice. The current status is either in the hands of the agency or the trademark registration applicant, and is no longer in the Trademark Office.