1. Choose a place to search
Google Patents is a good place to begin a patent search. There are many patent databases mentioned in this guide, but using Google Patents is an easy search tool for beginners and may lead you to other patent office databases and websites as you dive further into your search.
2. Choose a few keywords
When you decide to do a patent search, you should begin by thinking about the key words that you want to use. What I might call a screw, the patent examiner might call a fastener. What I might call a helicopter, the patent office refers to as a type of rotorcraft. Keywords are not precise but they are a good place to start looking.
ex: Helicopter Blades
3. Find a relevant patent
Using your keywords in Google Patents or a patent database, try to skim through your results. Are you finding patents that are relevant and related to what you're looking for? If you see any that are closely related, make a note of the patent number in case you want to go back to it. Then, look at the CPC Classification Number that is assigned to it. If you open a result in Google Patents, you'll usually see the CPC Classification number that was assigned to that patent under the thumbnail images. This number is saying that the patented invention belongs in a specific area of technology. Read the definition beside each classification number assigned to it and ask yourself if that definition would also describe your invention or part of it. Write down the classification numbers that are relevant and if this patent isn't relevant, keep looking at other results or change your search strategy using other keywords.
ex: Convertible Aircraft (US 3246861)
4. Search using classification numbers
Once you have identified classification numbers that define your area of technology, begin a NEW search in Google Patents. This time, only use the classification number. You "may" add key words, but remember that they might limit your results too much so that you miss something that uses a different term instead.
ex: B64C29/0033 (Aircraft capable of landing or taking-off vertically having its flight directional axis horizontal when grounded the lift during taking-off being created by free or ducted propellers or by blowers the propellers being tiltable relative to the fuselage)
5. Look through your results
When you have your results narrowed down to a sub-class where you have maybe 200 results or fewer (ideally), then start looking through your results to see if any of these patents are similar to the technology you are looking to protect. If they are similar, read the "Claims" section carefully to see if you have anything unique in your invention that isn't covered by the existing patent claims. For results that aren't relevant at all, cross them off of your list. If you find anything very similar that is concerning but you decide to move forward with filing a patent application, make a list of those patents for your patent attorney if you are seeking legal assistance.
Consider additional information
Patent searching is an ART, not a SCIENCE. While there is a suggested strategy, there are also other ways to approach it and further resources provided with each patent document that may lead you down a path to new discoveries. You may look at the "Patent Citations" to see what patents and publications led up to this invention or "Cited By" to see patents and publications that were published afterward (more recently developed). You could also conduct a new search using known companies or inventors who might own patents in the industry to see what your competition is coming up with.
"Prior Art" is essentially what is already known to the public. That can include patents or patent applications, books, articles, and other publications. Unfortunately, inventors sometimes disclose their invention when they publish their research or next steps in their research and that can be prior art as well. Prior art can also include online content such as websites, social media, YouTube videos, blogs, etc. It can include public disclosures such as trade show demonstrations, class presentations, etc. If an invention is already known to the public, then the patent office could not say that it is "new" in a patent application. In order for a patent application to be granted, the invention must be new, useful, and non-obvious. If you are the inventor and also the person disclosing your invention, you have one year to file your patent application in the U.S. without having the disclosure prevent your application from moving forward. However, foreign countries do not allow this one-year window of time for a public disclosure, so if you intend to file in other countries, it is safer to file before a disclosure.
Considering that prior art is encompassing all that is publicly known, it is generally a good idea to search patents, patent applications, and print publications at least. If you are a WSU student, faculty, or staff, you may access library databases off-campus. If you are not affiliated with WSU, you may still visit our Ablah Library at WSU to use community user computers to access these same databases.