First find the official intellectual property website and then open the Madrid trademark registration page and find the query entrance; then select the qualifying conditions according to the prompts and query the international registration announcement; finally, click on the image of the selected trademark or the international registration announcement in the announcement list. After the registration number, a PDF file containing detailed information about the corresponding trademark will be displayed, including the international announcement issue number, announcement time, applicant's name and address, trademark drawing, designated goods and services list, designated country list, etc. The opponent should submit an opposition application to the Trademark Office within 3 months from the 1st of the month following the international announcement.