• Swedish Patent Office (PRV)
• European Patent Office (EPO)
• US Patent and Trademark Office
• World Intellectual Property Organization (WIPO)
• Office for harmonization in the internal market (OHIM)
• Fédération Internationale des Conseils en Proprité Industrielle (FICPI)
• Svenska Patentombuds Föreningen (SPOF)
• Patents on the Internet
• World Intellectual Property Network
• http://ep.espacenet.com/

There are also a number of searchable databases:

• IBM Patent Server
• USPTO Patent Databases