Overturning a Patent

By David Carnes

A patent is a right to exclude others from making, using or selling an invention of yours. To be eligible for patent protection, the invention must incorporate original technology that has never been publicly released before. The U.S. Patent and Trademark Office, or USPTO, reserves the right to invalidate a patent even after it is granted, if it discovers that the patented technology is not original or that information about it was publicly released before the patent application was filed.

"First to File" vs. "First to Invent" Systems

Most of the world uses a "first to file" system of patent protection; when two inventors create a particular invention independently of each other, the first inventor to file for patent protection is entitled to the patent. The United States, however, uses a "first to invent" system, meaning that the original inventor can invalidate the patent of a subsequent inventor who filed for patent protection before the original inventor files.

Prior Art

The term "prior art" means technology already in existence that may be identical, or nearly identical, to technology for which patent protection is sought. Even after a patent is granted, the USPTO is authorized to invalidate a patent if it discovers by any means that identical technology was already in existence at the time the patent application was filed. Identical technology invalidates a patent even if patent protection was never sought for the identical technology.

File a provisional application for patent online. Get Started Now

Prior Publication

Original technology is not eligible for patent protection if it was marketed in the United States, or if its details were publicized anywhere in the world, more than one year before its U.S. patent application filing date. This means that if you publish details of an unpatented invention anywhere in the world, or market the invention in the United States, you have less than one year to file for patent protection. If you miss the deadline, your invention can never be patented. A major exception to this rule applies when you file a patent application under the Patent Cooperation Treaty. If you file a PCT patent application with the patent office of any PCT country, the publication of details of your invention by the foreign patent office will not set the one-year clock ticking in the United States or any other PCT country. As of September 23, 2011, 144 countries have signed the PCT.


You may challenge the validity of a patent by submitting evidence of prior invention, prior art or prior publication to the USPTO. The office will conduct a reexamination of the patent and will invalidate it if it concludes that it would never had issued the patent in the first place had it known of the information you provided. If you disagree with the decision, you may appeal to the Court of Appeals for the Federal Circuit in Washington, D.C. To appeal, however, you must demonstrate that you have legal standing to file a lawsuit against the USPTO. To have legal standing means that your interests stand to be affected by the decision; for example, if you are seeking to market the patented technology and someone else owns the patent, then you probably have legal standing.

File a provisional application for patent online. Get Started Now
What Does Patent Mean?


Related articles

What Is a WO Patent?

"WO" is a suffix to a patent number that indicates that the original patent application was filed under the Patent Cooperation Treaty, an international treaty that harmonizes the patent application process among member nations. Although the World Intellectual Property Organization oversees this process, it does not issue international patents; instead, applicants must complete the last phase of the patent application process with the patent office of each nation where they desire patent protection.

How Long Is a Patent Valid?

A patent is a governmental grant of a short-term monopoly to inventors. U.S. patent laws enable a patent holder to prevent others from making, using or selling the patented invention for a specific time period. How long a patent remains valid depends on the type of patent and other factors.

How to Calculate Patent Expiration

In the U.S., patent protections generally stay in force for twenty years, but the date on which this protection begins may vary. Once a patent expires, the invention may be freely copied, so knowing how to calculate patent expiration can be a valuable skill. In order to calculate patent expiration, you will need to know what kind of patent is involved and when its protection began.

Start here. LegalZoom. Legal help is here. LLCs. Corporations. Patents. Attorney help.

Related articles

Can You Get a Patent for an Idea?

You cannot patent an idea alone. If you develop the specifics of your idea, however, you might be able to patent it. A ...

How to File a Software Patent

A patent protects the legal right of the patent holder to prevent others from using or profiting from his invention ...

What to Do When Someone Steals Your Ideas

An unexpressed idea enjoys no legal protections. If you have fixed your idea in a tangible medium, such as by recording ...

How to Challenge a Patent

The U.S. Patent and Trademark Office (USPTO) grants patents to allow inventors to enjoy legal monopolies on the ...

Browse by category
Ready to Begin? GET STARTED