Alex is the co-founder and CEO of Patentext. He’s spent over a decade drafting patents for startups, unicorns like Uber and Dropbox, and everything in between. When he’s not obsessing over Patentext or running his climate tech-focused IP firm, he’s likely training for a triathlon or chasing a very fast border collie.
If you're here, you're likely trying to figure out how long you have left to file—or wondering if you've already missed your window. Let me give you the direct answer first.
There is no single, universal answer to "how long do I have to file a patent?" It depends on whether you're asking about the U.S. grace period, international filing windows, or the time between a provisional and a non-provisional application. Here's a clear breakdown of each.
The U.S. one-year grace period
In the United States, you have one year from the date of your first public disclosure to file a patent application. This is called the "on-sale bar" or "statutory bar."
A public disclosure includes:
- Any sale or offer for sale of the invention
- Public use of the invention
- A publication, patent, or patent application describing the invention
- A press release, blog post, or product announcement
- A demo or presentation at a conference or pitch event
- An investor presentation given without an NDA
If you hit any of these events, the clock starts immediately. You have exactly 12 months. Miss it, and you're permanently barred from filing in the U.S.
There's a common misconception that you can restart the clock by filing a provisional. You can't. A provisional locks in the priority date for the invention as described in it, but if you publicly disclosed the invention before filing the provisional, the on-sale bar clock started at the time of disclosure—not the provisional filing date.
International filing: no grace period in most countries
The U.S. grace period does not apply internationally. Most countries, including all EU member states, Japan, South Korea, and China, require absolute novelty. This means any public disclosure before filing—even a single day before—destroys your patent rights in those countries.
There are narrow exceptions in some countries (Canada, Australia, and a few others have limited grace periods), but you should not rely on them for strategic planning.
Practical implication: If you intend to file internationally—which most startups selling into global markets should at least consider—you should file before any public disclosure, including going public with your idea, can cost you the right to patent it at all. Even a placeholder provisional can lock in your priority date while you work on next steps.
The provisional-to-non-provisional window
If you've already filed a provisional patent application, you have 12 months from the provisional filing date to file a non-provisional (utility) patent application that claims priority to the provisional. This is a hard deadline with no USPTO extensions.
Miss this deadline and:
- The provisional expires and the priority date it established is permanently lost
- Any prior art that accumulated during the provisional period (including your own public disclosures) can be used against you in the non-provisional
- You may need to refile as a new application, with a new priority date
Set a calendar reminder when you file your provisional. You need to either convert or consciously decide to abandon the provisional before the 12-month mark.
How to calculate your deadline if you've already disclosed
If you've already had a public disclosure and haven't filed yet:
- Identify the earliest date of any public disclosure of the invention. Be thorough—include any investor meeting without an NDA, any demo, any blog post or press release.
- Add 12 months. That's your U.S. filing deadline.
- File a provisional or non-provisional before that date.
- For international filing: you've likely already lost rights in most countries if the disclosure was made without a prior filing. A patent attorney can help you assess what's salvageable.
How to avoid running out of time
The most common reason founders miss their patent window isn't negligence—it's simply not knowing the rule existed. Here's how to stay on the right side of the deadline:
- File before you go public: Before any press release, product launch, demo day, or investor meeting without an NDA, file at least a provisional.
- Treat demo days as public disclosures: YC Demo Day, Techstars Demo Day, and similar events are public. If you're presenting an invention, file a provisional first.
- Use NDAs strategically: Disclosures under NDA don't trigger the grace period, but NDAs aren't always honored and don't protect your international rights in any case.
- Set a calendar reminder when you file a provisional: The 12-month conversion window is a hard deadline.
What happens if you've already missed the deadline?
If you've missed the U.S. one-year grace period, you cannot file a U.S. patent on that invention. There are no extensions and no workarounds.
If you've missed the provisional conversion deadline, you've lost your priority date. You can still file a new application, but it will have a new priority date and will be subject to any prior art that accumulated in the interim.
In either case, the right next step is a consultation with a patent professional to understand exactly what IP, if any, is still protectable.
Get started before the deadline
Patentext helps startup founders file provisional and non-provisional patent applications quickly—so you can establish a priority date before your next pitch, launch, or public disclosure.
This article is for informational purposes only and does not constitute legal advice. Patent laws are complex and vary by jurisdiction. For personalized guidance, consult a qualified patent attorney or agent.