All patent databases are different, but these general search strategies will provide you with a starting point. You may want to look for search instructions on the individual database websites.
Known information:
If you know the document number, inventor, owner, exact title of the invention, etc., then you can look up patents by searching in those specific fields. Searching for the product name in a trademark database (such as the Canadian Trademarks Database or the United States Patent and Trademark Office Database) may help you find the name of the owner. You can also check the product or packaging to find a visible patent number or company name*. Remember to check the company's website, as they may have published information about their products online.
*Remember that the company that distributes a product may be different than its manufacturer.
Dates:
You can search for specific dates, or a date range, in fields such as issue date, filing date, priority date, and others.
Keywords:
Brainstorm keywords related to the purpose, use and composition of the invention. Ask yourself whether there are synonyms (equivalent words) for these keywords (e.g. backpack, knapsack, rucksack...). Limit your keywords to the title and abstract.
Remember that product names come after the invention has been patented, so searching for "post-it note," for example, will not retrieve the invention you are looking for.
Most patent databases will allow you to combine keywords using the same strategies that you use in article databases. For example, you can use Boolean operators (AND, OR, NOT, etc.) and nested queries, truncation (e.g. cut* instead of cuts, cutting, cutter, etc.) and phrases in quotation marks ("cutting board").
Searching for patents can be a complicated and time-consuming process. Of course, if you know what you're looking for, then you can always search by patent number, inventor's name, or company name. But if you're just beginning to explore and you want to know what's out there, then doing a keyword search or browsing the appropriate classification index will probably be more helpful. You could also try looking up a known invention, finding its classification code, and browsing for similar inventions within the same category.
International Patent Classification (IPC) System
European Classification (ECLA) System
Canadian Patent Classification (CPC) System*
U.S. Patent Classification (USPC) System
*The CPC is only used for Canadian patents issued before October 1st, 1989. Canadian patents issued on October 1st, 1989 and after are classified according to the IPC System.
