Kaufhold & Dix Patent Law
Protect Your Intellectual Property — Call Kaufhold & Dix at
For A Free Consultation

on sale bar doctrine

The On-Sale Bar Doctrine And How It Can Affect You

What is the on-sale bar doctrine, or, as it is also known, the one year bar date?

In a nutshell, in the United States the on-sale bar doctrine, or one year bar date, means that if your invention is public for more than one year prior to filing for protection on it, you cannot file for protection and lose all rights in your invention. To be public includes making, using, selling or in any way displaying or disclosing your invention publicly, anywhere in the world, more than 12 months before you file for a patent. Offering for sale is nearly always considered “public” regardless of how private the offer. The Supreme Court recently held that this is a very strict rule such that even secret sales start the clock.

Example 1:

You make your invention in your garage and sell it at flea market in Minneapolis, Minnesota on July 1st, 2020. If you do not file for protection by July 1st, 2021, you will lose all rights in your invention.

Example 2:

You describe your invention on a private social group webpage, in a small southern Minnesota town on July 1st, 2020. You must file for protection by July 1st, 2021 to avoid losing your rights in your invention.

Example 3:

You make your invention and place an ad for it in a small town northern Minnesota newspaper on July 1st, 2020. The paper has a small distribution, you never have any phone calls asking about your product, and you never make any sales. You have no evidence that anyone in Minnesota, or anyone in the world for that matter, knows about your invention. You still must file by July 1st, 2021 because the mere offer of sale triggers the one year bar date calculation.

Example 4:

You are a Minnesota company but want to make the invention in China. Beginning on July 1st, 2020 you develop the product with a Chinese manufacturer and you ultimately produce 100 units and those are sold in China, beginning on September 1st, 2020. The on sale bar is one which is effective anywhere in the world. Thus, even if your product is only made in China and is never shipped back to the US for sale in Minnesota, you still must file for protection in the US within 12 months of the first public disclosure. In this particular scenario, you could have an argument that it was not public until September 1st, 2021, but you would be safer to file by July 1st, 2021 as the development of the product with a third party, under certain circumstances, could be viewed as a public disclosure.

Are there exceptions to the one year bar date?

There is a notable exception to the one year bar date and there is also a work-around. The exception is where the invention is still in development and the inventor is testing the invention to see if it functions as needed. If the essence of the invention is not publicly disclosed or the invention is used but maintained in secret for testing purposes, then the one year bar clock may not start.

Example 5:

You enjoy boating in Minnesota lakes and rivers but are not satisfied with your boat propeller. You invent a new propeller on January 1st, 2020 but cannot get into the lakes or rivers since all of Minnesota is frozen over. However, after the ice is gone, you take out your boat with newly the developed propeller on May 1st, 2020 and try it on several Minnesota lakes where others see your boat in the lake but do not see the propeller. You tell no one about your invention and you don’t show anyone your new configuration. You decide its perfect, and you begin to tell and show people on July 1st, 2020. The time from January 1st to July 1st 2020 was secret, experimental, and did not start the one year bar date clock. Consequently, you must file by July 1st, 2021 to keep your rights.

Example 6:

You develop new asphalt made for the extreme hot and cold variances of the weather in Minnesota. You obtain the ability to pave a small section of roadway in southern Minnesota with your new asphalt for testing purposes on July 1st, 2019. You do not tell the Minnesota Dept. of Transportation that you are using your new asphalt for a small section of the roadway. You need many years of testing since longevity is the key to the success of you product. You realize on July 1st, 2025 that the product is perfect and no more testing is needed. In this scenario, the one year bar date calculation has not started. While the asphalt was used in a public setting, there was no sale and no one driving on it (presumably) knew that it was anything but ordinary asphalt. Thus, it is still secret from a legal perspective.

The work around to the on sale bar/one year bar date is that any alterations start a new one year bar date for those alterations dated from the time that those alterations become public. Thus, you can file for protection on those alterations as long as you are within the one year bar date timeframe of the alterations themselves. The alteration need not be critical, but it does need to be relevant and will have to be claimed in the patent application.

Example 7:

As a modification to Example 5, you sell your propeller on July 1st, 2020 but never file for a patent and it is now August 1st, 2021 which prevents you from now filing as more than 12 months have elapsed. You find yourself in a Minnesota lake with excessive vegetation and your new propeller seems to get caught up in it more than other propellers. On September 1st, 2021 you re-design a portion of your propeller so that it does not capture the vegetation. You can now file for protection as long as you include your new and are within the one year bar date timeframe for that alteration.

Conclusion - Your situation is unique

The above is a general overview and should not be considered legal advice as the above may not pertain to your specific situation. There are also some risks associated with relying on the one year bar date instead of filing immediately for protection before making your invention public, and the determination of what is or what is not “public” can be tricky. You are therefore encouraged to contact our firm, Kaufhold & Dix Patent Law, located in Edina, Minnesota and in Sioux Falls, South Dakota, so that our skilled practitioners can answer questions related to your particular circumstances.



Sean Kaufhold is a founding partner of Kaufhold & Dix Patent Law, a boutique firm specializing in Intellectual Property. He is a patent attorney serving clients who require assistance with patent searches and opinions, patent application preparation and prosecution, trademark application and prosecution, patent litigation advisement, infringement opinions, and clearance studies. Mr. Kaufhold also serves as an advisor for companies as they evaluate current and future intellectual property strategies.

Don't risk losing your intellectual property rights by failing to act.

Register for patent, trademark or copyright protection by calling Kaufhold & Dix at 612-216-1161.

Contact An IP Attorney Today

Email Us For A Response

Edina Office
7400 Metro Blvd, Suite 420
Edina, MN 55439

Phone: 612-216-1161
Edina Law Office Map

Sioux Falls Office
6330 S. Western Ave, Suite 100
Sioux Falls, SD 57108

Phone: 605-334-1571
Fax: 605-334-1574
Sioux Falls Law Office Map