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Using CASSIS to Search for Patents & Trademarks


Searching for Patents

  1. Find the subject category that best describes your idea.
    1. Patents are arranged in categories called classes and subclasses. Use the Index to Classification – an alphabetical list of subject headings referring to specific classes and subclasses – to find the class and subclass numbers for your idea.
    2. Look up words that describe your idea and you will find hints to class and subclass numbers.
    3. Then find the class/subclass numbers in the Manual of Classification – the up-to-date, complete list of subclasses. The list is in outline form with items indented under major headings.
    4. Choose the appropriate numbers, for instance, class 128, subclass 10.1A
  2. Use the CASSIS database to get a list of patents
    1. Select the Home icon or click on “Cassis2 User Interface”
    2. Select Patents BIB
    3. Using subject area code numbers
      1. When the patent menu appears, select the field Current Classification.
      2. Type in your class and subclass numbers with a slash between them: e.g., 128/10.1A
      3. Click on Search.
      4. Click on Results to see the list of patents.
      5. To print the list, click on the print icon.
      6. You can do the same search using the Command Search option.
    4. By words in the patent title. Just type in your search terms in the title field.
      Note: This is a word-specific search. You might miss items that haven’t used the words you expect. There is no substitute for the correct class/subclass combination. eg: The word “frisbee” will yield only 63 patents, if you look it up under the class Amusement Devices (446/46) you get 155 patents.
    5. For a list of patents owned by a company, search the “assignee” line.
    6. To find patent numbers before 1969 (titles will not be listed), select “Patents Class” from the menu and enter the class/subclass.
    7. To search for an inventor, choose “Patentee-Assist” and then choose “Inventor-Assignee Index” from the menu. Type the first and last names of the inventor you’re looking for.
  3. Read details of individual patents
    1. You may look at abstracts in the Official Gazettes. They are arranged by the numbers you printed out from CASSIS. Please use no more than 6 at a time.
    2. Apart from the USPTO’s website you can also find the full-text on microfilm and DVDs (USAPAT on Cassis)


Searching for Trademarks

  1. Select the Home icon or click on “Cassis2 User Interface”
  2. Select “Trademarks BIB”.
  3. Select the field “Word Mark” and type the word or words you want to check.
  4. Click on Search; the computer will search the word combination and show how many items were found.
  5. Click on Results if there are any entries.
  6. To print the results, click on the print icon.
  7. Use CASSIS or the Trademark Official Gazette to find a copy of the trademark logo.
    1. Write down the date published, the international classification number, and the serial number.
    2. Use this information to find the Gazette by the date the TM was published.
    3. Within the Gazette, find the section for the particular international classification.
    4. Within the class listing, the logos are arranged in order by serial number.
    5. If more than one class is listed, search the Gazette by the serial number in the section marked “Applications in more than one class.”

You can also search for trademarks at the USPTO’s website.

Tips for Trademark Searches

  • If the word you check is very common, the list may be too long to read. You can narrow the list by combining it with a second important word. You can also type the kind of product on the line marked “Goods and Services” – words like: clothing, game, consultant, or restaurant.
  • The same trademark may be owned by different users if the products are sufficiently diverse. Conversely, if the product is not substantially different, you may not be able to use a similar trademark. Speak with a trademark attorney for advice.
  • When checking for the name of a company, remember that company names do not have to be trademarked. You should check the database for any names that might be there, but you must also go to a business library and check directories of company names.
  • When searching the database, check only important words from the name; don’t use articles or generic words like “company,” or “incorporated,” or “consultants.”
  • Federal trademarks are used to protect names in interstate commerce. Names used for local products and services may only need to be registered with the state. Check to see if the name you want to use has already been taken at the state level. If it hasn’t, contact the Department of Corporations, 1 Ashburton Place, Boston, MA, 617-727-8329.

Check the USPTO website for additional instructions on how to use the CASSIS database.