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Primary Patent Search Tools

Patent Law And Treaties

Patent Searching Tips

Example for searching for a impeller for a centrifugal pump, using any of the Primary Search Tools:

  • At the next screen input "centrifugal pump" in term 1 box, then input "impeller" in term 2 box
  • Or if just working with one search bar type, "centrifugal pump" AND "impeller"

If you don't like your results, try using a USPTO Classification Code to look up the exact controlled search term. For example if you are working with a washing machine, you may need to try "agitator" instead of "impeller".

Patents Granted By Other Countries

What if there's NOTHING similar patented?

  • Be EXTREMELY skeptical. Patent researchers know that every innovation comes from “prior art.”
  • Use Classes arranged in Alphabetical Order   (or similar term in other country's patent site) to find the best category for your idea.  Patent classification schedules are very detailed.
  • On the Patent Office home page, type the category number in the A1 Enter a US Patent Classification field (or similar field in other country's patent site, using that country's class arrangement))  The U.S. class field is at the top left.of the site.
  • Click “submit” and then look through that list to determine where your idea fits.
  • Be sure to go all the way down the list to the "Cross Reference Art Collections"(or similar term in other country's patent site)  to check for other categories.