HomeLog inRegister


 Patent Searching basics

Go down 
Bill Goldblatt

Bill Goldblatt

Patent Searching basics Empty
PostSubject: Patent Searching basics   Patent Searching basics EmptySat Jun 20, 2009 7:10 pm

A truly competent professional searcher should have the experience and derived expertise, and at times subscription based tools, to conduct patent searches more efficiently that you can. That said, if you have a good internet connection, you tend to have access to the same databases any professional searcher or USPTO examiner has access to. It is perfectly possible to conduct a good search on your own. If you are on a budget, it might make a lot of sense to do so. If nothing else, it is often smart to see what you can find yourself before paying anybody to find it for you.

There are three methods of patent searching (which can be combined via boolean searching):

Classification searching: The USPTO classifies patents into different classes and subclasses – an index can be found here -


ECLA Classes (the ECLA system derives from the European Patent Office as an improvement on the traditionally used International Classification system) -


Keyword Searching: You can search patents using keywords.

Reference Searching: Most patents reference similar prior art, and may be referenced by other patents as well.

Classification searching still seems to be a staple at many patent search firms and law offices (it was the only realistic way to search pre-internet). Classification searching can still be far more accurate than conducting keyword or boolean searches that do not take classification into account. The problem with sticking solely to classification searching however - particularly in this day and age, and particularly when you are searching US patents - is that you have more and more applications being filed, more and more convergence of technologies and such, and you have tired examiners and no consistent authority for determining and selecting the proper classification(s) of a patent. Yes, some searches, you can search two subclasses and be done with a very respectable search. But other searches, there literally may not even be a list of 50-100+ subclasses that could potentially be likely to contain relevant patents. I find that most searches I conduct fall somewhere in between the two extremes.

Also, published applications are routinely mis-classified...

In the past, this was somewhat besides the point, because it was simply not time or cost effective to look over every patent in 50 different subclasses. However, modern search tools (like Delphion or to a lesser extent even the USPTO's online resources or freepatentsonline.com) provide the ability to form complex search criteria, allowing you to search a narrow or wide range of classes/subclasses, further narrowing results down by various keywords and keyword combinations, keyword modifications and synonyms, proximity, etcetera.

If you know what you are doing, taking advantage of this tends to make for an effective supplement to a thorough review of the most relevant subclasses. "Back-checking" via classification-less boolean searching with more narrow keyword criteria, and a review of references cited by the patents you have located can also be useful.

Some last notes: there is no one way to conduct an ideal search, and not all searches are equal, and should be treated according to whatever makes sense; within patent publications, various products and their features are not always described in a conventional manner; Also - where the purpose of a patent search is to determine patentability, searching for non-patent prior art (which just about refers to anything that isn't a patent) is as relevant as searching patents.
Back to top Go down
Patent Searching basics
Back to top 
Page 1 of 1

Permissions in this forum:You cannot reply to topics in this forum
 :: Patents Trademarks and Copyrights :: Researching Patents-
Jump to: