Can I Patent Something That’s Already on the Market?

Q: Can I patent something that is already being sold?

In the United States, yes—if it’s been less than 12 months since the first public disclosure. In most other countries, once it's on the market, it’s no longer patentable.

Q: What is the one-year grace period in U.S. patent law?

The one-year grace period allows inventors to file a patent application within 12 months of publicly disclosing or selling the invention.

Many inventors wonder if they can still file a patent for a product or idea that’s already available for sale. The answer depends on when the invention was first publicly disclosed and where you plan to file the patent.

The One-Year Rule (United States)

In the U.S., you have up to one year from the date your invention was first:

Sold
Offered for sale
Published publicly
Displayed at a trade show

This is known as the "grace period." After one year, you lose the right to patent that invention in the United States.

No Grace Period in Most Other Countries

Most other countries, including those in Europe and Asia, require absolute novelty.

Any public disclosure before filing makes your invention unpatentable.
There is no grace period — you must file first.

What Counts as Public Disclosure?

Public disclosure can include:

Selling the product online or in a store
Showing the invention at a conference or event
Publishing a video, blog post, or whitepaper
Sharing details in a pitch deck without an NDA

Exceptions and Workarounds

If the invention is not yet publicly disclosed, you may still file.
You may file in the U.S. even if the invention is on the market, as long as you’re within the 12-month window.
If the product has changed, consider filing a new patent for the improvement only.

What If Someone Else Patented It First?

If another person filed a patent on your invention before you did, they likely hold the rights—even if you developed it first. File as early as possible to avoid losing priority.