There are many ways to find prior art (books, thesis, magazines, patents, etc etc).

When doing online prior art search, what tools and databases do you use?

4 Answers 4


In my corporate life I used paid services such as Micropatent and TotalPatent. Of the free patent search tools, I prefer The Lens over Google patents. The Lens provides more fine grained control and if you register (completely free) provides useful additional features such as saved searches, search history and collections. In addition, I find The Lens provides more accurate searches. Google Patents sometimes, inexplicably, doesn't find patents that The Lens does. I also think Espacenet is really useful for patent searching. There are other good options. I've heard decent things about Free Patents Online, but haven't used it much myself.

I do use Google Scholar for non-patent searching although I do think paid services are probably stronger. The Lens has some new capabilities in this area, but it is immature as yet. Other sites you might try out are Microsoft Academic, Science.gov, PubMed Central, and WordWideScience.org.

There is a lot of skill to doing prior art searching and professionals are really useful as resources. I've worked with professional patent librarians and they use techniques such as patent classification codes to make searches more accurate. If you are associated with an academic institution, you should really consider utilizing your school's library and librarians.

  • Btw, there is no "www.google.com/patents" anymore. It directs now to "patents.google.com". Google changed it few days ago.
    – Mikk Putk
    Commented Feb 23, 2018 at 19:03
  • 1
    @MikkPutk Thanks! That is great news. I edited the answer to reflect this change.
    – Eric S
    Commented Feb 23, 2018 at 23:30

Google patents, google books, google, patbase and library catalogues sometimes.

I haven't seen any tools delivering (good/better) natural language results or anything like that (though many promise to).

I'd love to be proven wrong on this one as a search is just tedious work, but as of now I haven't seen anything beat a good old

search - understand what you're finding and why / why not what you were looking for - search more

approach with varying keywords.


Well it depends on what's the purpose of prior art search and who's doing it.

For example: If an inventor wants to do a prior art search just to determine if his invention is new or not, the easiest to use that I have come across is PQAI

However, if the purpose is invalidation, help of a professional or a skilled prior art searcher might be needed.

I also used PQAI to do free lance prior art search, the results were quite impressive and the search was quick.

I have shared my experience as a free lance prior art researcher in the video below:


  • Welcome to Ask Patents. This is a nice new resource I was unaware of. Just to be sure, if you have any association with PQAI it would be best to acknowledge it in the answer. I hope you enjoy contributing to Ask Patents.
    – Eric S
    Commented Dec 11, 2020 at 20:29
  • I agree, even though it is an open source, non-commercial site.
    – George White
    Commented Dec 11, 2020 at 20:41

TotalPatent One - https://www.totalpatentone.com/search


Comprehensive Content The world’s largest and deepest collection of patent data from around the globe.

Speed & Efficiency A faster, more efficient user experience and no waiting for pages to load.

Intuitive & Easy to Use A simplified user interface enables you to easily find the patent search results you need.

  • Sounds like an excerpt from a sales pitch. Are you affiliated with them?
    – George White
    Commented May 30, 2019 at 23:57

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .