IP Resources


Patents and Patent Searching

Patent Searching - The main methods of patent searching are keyword searches, field searches and classification searches.

Patent numbers are unique identifiers assigned when a patent is published and are standardized to the form CC 123456789 KK, where CC is the country code and KK is the kind code.

Patent Information Sources - The resources below were selected either for being primary sources (patent agencies), providing specialized search functions (free web sites and licensed databases), or for particular strength in a STEM field

  1. US Patent and Trademark Office (USPTO)

    The U.S. Patent and Trademark Office is the primary, authoritative source for United States patent information.

  2. European Patent Office (EPO) Espacenet

    The European Patent Office's search engine Espacenet is the largest worldwide patent database, with over 80 million patents.

  3. World International Property Office (WIPO) PatentScope

    Although more limited coverage than EPO's Espacenet, with 37 million documents PatentScope is still useful for its specialized search tools and data

  4. Google Patents

    After starting with scanned USPTO documents, Google has expanded their patent search to include international patent organizations.

  5. The Lens

    Formerly known as Patent Lens, the Lens is an online search tool for patents that offers some unique features. After signing up for a free account, you can build collections of patents to create graphical reports and download spreadsheets of bibliographic data from a collection.

  6. FreePatentsOnline (FPO) / SumoBrain

    The FreePatentsOnline (FPO) web site is a useful source of PDF patent files and RSS feeds for new patent information. RSS feeds will push updates when new patent documents are published in a specified classification or in one of FPO's technology areas.

  7. Derwent World Patent Index - Thomson Reuters (subscription)

    The Derwent World Patent Index adds additional information to patents such as: uniform assignee information (ex. the many permutations of IBM), enhanced titles and abstracts simplified into layman's terms, and its own proprietary classification system (Derwent class codes and Derwent manual codes).

  8. SciFinder Scholar - Chemical Abstract Service (CAS) (subscription)

    The American Chemical Society (ACS) has been indexing chemical patents through CAS since the early 20th century. Today, CAS has patent information from many international patent offices, often within days of publication (check for current years of coverage).

  9. Reaxys - Elsevier (subscription)

    Reaxys from Elsevier, based on the Beilstein and Gmelin databases with added patent data, offers many of the same tools and data as SciFinder Scholar.

  10. SureChem

    SureChem is a free web site offering similar data and search functions as SciFinder Scholar. It has keyword searching and structure searching of documents from the major patent sources (USPTO, EPO, WIPO, and the Japanese Patent Office).

End-User Patent Searching Using Open Access Sources

  1. U.S. Patents
    • PATFT

      The USPTO's PATFT searches and serves over 7,000,000 patents, all three types of U.S. patents (utility, design and plant).

  2. International Patents
    • Esp@cenet

      The European Patent Office's (EPO) patent search engine, Esp@cenet, provides an interface to search for published patent applications in over 80 countries. The provision of full text vs. abstract/citation varies with the home country's database.

  3. Searching Patents - Keyword Searching - Government Sites
    • PATFT -- keywords search patents from 1976 to the present

      All patents are in TIFF, the most "lossless" image format. Patents issued after 1975 also exist in HTML (full text).

    • Industrial Property Digital Library

      The JPO (Japanese Patent Office) serves patents from their Industrial Property Digital Library.

    • SurfIP

      SurfIP, the Singapore government's patent database, has a structured search that accesses any or all of the following countries' patent information: U.S., China, UK, Canada, Taipei, Korea, and Thailand.

    • CIPO

      The Canadian Intellectual Property Office (CIPO) database has full patents back to 1920 with text searching for patents back to 1978.

    • Patent Analysis

      Countries like Australia and New Zealand have put patent information online in the last few years. Patent Analysis searches both along with the U.S. and European patents.

  4. Searching Patents - Keyword Searching - Non-government Sites
    1. Google Patents

      Google Patents searches only U.S. patents, although they have plans for a global reach.

    2. Freepatentsonline

      Freepatentsonline has search fields similar to PATFT. It searches U.S., EP, (European), JP (Japanese), and WO (PCT) patents.

    3. Patent Lens

      Patent Lens, created by CAMBIA, an independent, international non-profit institute, has a structured search and range of coverage similar to SurfIP.

  5. Classification Searches

    Subject searching is the most powerful search for obtaining relevant results, as long as the correct subject terms are used.

    There are two major patent classification systems: Current U.S. Classification (CCL) and International Patent Classification (IPC), sponsored by WIPO to better coordinate searches among countries across the world.

    1. CCL Classification

      Aids for CCL include the Index to the Patent Classifications, and the Manual of Classification, listings by subject and classification number, respectively. A CCL search is executed by Class/Subclass code, e.g., 501/13 [Class (Compositions: Ceramic)/Subclass (Radiation color change responsive)], or 501/$ for searching an entire class. The search term would be: CCL/501/13

      To determine which class/subclass to search:

      1. Use a narrow keyword search, identify relevant patents and check to see the primary class (usually listed first and bolded) designation, or
      2. Search the Index by keyword. In the results list the active class/subclass link transfers to the Manual listing (as if you had done the classification number search).

        On the manual list the active subclass number gives a full definition of the subclass. Sublevels, indicated by the number of dots in front of the caption, are confusing. A drop down menu at the top of the list allows you to hide sublevels. For instance, "Indent Level 1" will show the main subclass and the first level under it (those preceded by one dot). The active link preceding the subclass number leads to a list of patents (P) or applications (A) in that class/subclass.

        USPTO also has The 7-Step U. S. Patent Search Strategy for a Quick Start.

    2. International Classification
      1. WIPO Reformed IPC

        The CCL is more specific, but most foreign patents use their own or IPC classification. IPC code uses a SectionClassSubclass (alphanumeric code) Group/Subgroups display. For example, C03C 4/04 is a code that comes from Section C (Chemistry; Metallurgy), Class 03 (Glass, Mineral or Slag Wool), Subclass C (Chemical Composition of Glasses, Glazes, or…), with Group 4/Subgroup 04 (for photosensitive glass).

      2. U.S. to IPC Concordance

        A Concordance on the USPTO site provides CCL equivalents to IPC and vice versa. To search by IPC (ICL field code) in PATFT, substitute a zero for the space. The search above would be: ICL/C03C004/04

        EPO has its own classification system, ECLA, which also extends the IPC. JPO has two basic classification systems: FI (File Index), an extended IPC with technology areas having a further extension, the multi-dimensional F-Term indexing

      3. PatentScope

        PatentScope, a database of PCT patents, has patent fields designated by INID (Internationally agreed Numbers for the Identification of Data) codes, another WIPO sponsorship, to enhance the ability to find field information in a foreign language patent. The bracketed code precedes the fields. (e.g., [11] is patent number, [54] is title, [45] date of publication).

  6. Obtaining Patents

    As mentioned above, many search sites offer PDF or TIFF downloads for the full document.

    1. U.S.
      1. PATFT

        To protect the site from massive downloading (some patents are thousands of pages long), the patents on PATFT print one page at a time. InterneTIFF, one of the TIFF-viewer choices, can send all patent pages to the printer together. Downloading a patent may not be necessary if bookmarking will suffice. U.S. patents have persistent URLs. A hyperlinked listing of desired U.S. patents can be maintained as long as there is a clear indication that the link leads to the USPTO site.

        U.S. patents are also available in print and microfilm at and from the Patent and Trademark Depository Libraries (PTDLs). The Scientific and Technical Information Center (STIC) - collections include U.S. and foreign patents, and they are open to the public with trained staff to assist.

        Other sites (e.g., Google and Freepatentsonline) provide a PDF of U.S. patents as well.

    2. International

      SIPO provides machine translations for the Chinese patents with 85% correctness.

      PO has a new software search engine for Japanese patents, {JP-NETe}, that provides machine translation downloads for a fee. It outperforms PAJ by providing more current searches.

      Paterra has machine translations for patents back to 1996 from Japanese, Korean, Chinese, Russian, German and French.

  7. Patent Applications
    1. AppFT
    2. FreshPatents.com

    AppFT and FreshPatents.com search U.S. applications.

    For those wishing to monitor the latest patent applications, there are RSS feeds and alert services available with some sites (e.g., FreshPatents.com and freepatentsonline.com).

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