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If you only have a pre-1976 patent date, you also may be able to find the patent if you can hit upon the correct class for the item (see "Tools to Help..." above) and track the patent down, hit and miss.
You cannot "Advanced Search" by date or inventor's name, etc.
Defensive Publications (T) and Improvement patents (AI) are not included in this table.
The user should note that while the data in this table have been checked, it still is possible that inadvertent errors remain.For example, if you find something with a patent number of 1,941,448 on it, you will find in the chart below that it was patented in 1933. Always remember, patent date is only when something was patented, not when it was actually made, many items were manufactured for many years after it was patented.You can also obtain classification numbers at "Tools to Help in Searching by Patent Classification" at step 3.You now have a list of patents of a particular class for the range of years you have specified, and they will be in chronological order based on the date of the Tuesday of the week in which the patent was granted.