If you simply wish to determine whether a trademark is in use, searching te web with Google or other search engine can be useful. For graphic trademarks, Google Images (https://images.google.com/) allows you to search both y keyword and by uploading the image you wish to search for.
For more formal trademark searches:
- Most state trademark agencies have a search capability. For example, the California Trademark Search (https://tmbizfile.sos.ca.gov/Search) lets you search trademarks and service marks registered in the state of California. It does not have a graphic ssearch option.
- The United States Patent and Trademark Office (USPTO) has a trademark search at has the Trademark Electronic Search System (TESS) (https://tmsearch.uspto.gov/bin/gate.exe?f=tess&state=4803:k258di.1.1). TESS lets you search by keyword. While it does not have a direct graphic search option, it usese the Design Search Code Manual (https://tess2.uspto.gov/tmdb/dscm/index.htm) to enable you to identify design elements.
- The World Intellectual Property Organization (@IPO)'s Madrid System offers tools for searching trademarks internationally. See https://www.wipo.int/madrid/en/how_to/search/ for more information.
- DesignView (https://www.tmdn.org/tmdsview-web/#/dsview) is a search system covering over 20 million designs from the European Union and beyond. You may search by keyword and/or uploading a graphic image for searching.
- You can find a list of international trademark databases at the Patent and Trademark Resource Center Association website (https://ptrca.org/trademark/)