How to use expired or abandoned patents

My wife and I are in the process of creating/inventing a new baby product (we have 15 month old twins) and I have been loosing sleep trying to figure out how one feature of our product will work.   The problem is not very technical and a simple device would be able to solve our dilemma but I have not been able to figure out what the device should look like or how exactly it would work.  Since it's such a common problem we are trying to solve, I realized that someone at some point in the past 100+ years must have filed a patent to try and solve this problem so why not see what's out there at the patent office and use that instead of re-inventing the wheel.

The point I am trying to make here is that expired or abandon patents are in the public domain and are free to use.  Patents expire 20 years from the date they are filed so any invention that is over 20 years old probably is free for you to copy without violating a patent (you should check with an attorney to make sure).  Another way you can use a patent for free is if it becomes abandoned.  Patents become abandoned when the inventor gives up during the patent process or decides to not pay any more fees.

Here is how to find patents in your area and then see if they are expired or abandon:

Step 1 - Do a patent search (my free patent search guide is here) to find patents on an invention or problem you are trying to solve.   You can use powerful search engines like Google Patents Advanced Search feature to narrow your results to patents that were filed more than 20 years ago:    Write down or copy/paste the patent number or publication number of patents which you might want to copy.

Step 2 - Go to the USPTO Patent Center site.  Search by either patent number or publication number (if its an application):  Be careful of formatting.  If your search does not return any results its probably because you included an extra comma or your formatting was wrong.

Step 3 - Check the patent status section to see if it is Active (it will say "Patented Case"), Expired, or Abandoned.  In the example below this patent was active.

expired patent





If I found an expired patent I may be able to copy their claimed invention for free.  Someone else did all the hard work and I get the benefit of using it.  That is what makes our patent system so great.  It allows you to build from and improve the work of others and helps foster innovation.

(note:  it is always a good idea to check with an attorney before you copy someone else's patent even if its abandon or expired, there is a chance the inventor may have filed other related patents to the one you are looking at so even if one is expired they may still have active patents out there).

Please ask your patent questions on our free patent forum here


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