Most patent-specific databases are maintained by patent offices as freely available resources.Effective use of these resources generally requires some knowledge of the underlying data structure and familiarity with Boolean queries.

The European Patent Office and the US Patent and Trademark Office support two of the most widely used patent search websites. Of these, the EPOís ESPACE site provides a more user-friendly interface and access to more documents. The USPTO databases provide additional search fields and the ability to dig deeper within a reference (e.g., by use of the Public PAIR resource).


Things to do

       Start with a keyword search on a general-purpose search engine and poke around until you find a patent document that is at least close to the subject matter youíre interested in. Then use both classification and citation searching tools to find related references.

       Use the classification code from the front page of a patent document to find other references in the subject area of interest. Once youíve found a likely class, investigate the way that class is defined within its hierarchical classification system. Note that there are several different classification systems that youíre likely to encounter. Thereís no hard and fast rule, but a good classification search usually hits 2-3 classes and a total of 5-10 subclasses.

       Citation search tools can lead you to earlier patents cited during examination and to more recent ones that cite the reference youíve started with.Recognize that if the starting reference is a newly published unexamined application, chances are that the search will not turn up any hits

Some DONíTs

       Donít believe any search that tells you Ďthereís nothing like it out thereí. Thereís always something like it out there.

       Donít think that a title captures the essence of what a patent is all about. Titles are often overly general.

       In reviewing a list of US patents in a subclass of interest, donít stop when the list runs out of titles and displays only patent numbers. Those apparently incomplete list entries are the older references that often show the basics of the technology.

       Donít expect that ďno hitsĒ means what it says. The default error message in a structured database often means that your search syntax was wrong.

       Donít stop after looking at ESPACE and USPTO. Be sure to check other major patent databases as well as non-patent references available through your favorite internet search engine.

David A. Kiewit
Registered Patent Agent
5901 Third St. South
St. Petersburg FL 33705-5305
+1 (727) 656-0669 voice

+1 (760) 841-0989 fax
questions to: [email protected]
Copyright 2002-2017 by David A. Kiewit
All rights reserved



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