What Is a Provisional Patent? A Founder’s Guide to Protecting Your Idea

This guide explains how provisional patent applications work under US law. It is general information, not legal advice, and it does not create an attorney-client relationship. Patent decisions carry deadlines that cannot be undone — talk to a registered patent attorney or agent about your specific situation.

Let’s start by correcting the phrase in the title, because it matters.

There is no such thing as a provisional patent. There’s a provisional application for patent, filed under 35 U.S.C. 111(b). It never becomes a patent, never gets examined, and gives you no right to stop anyone from doing anything.

What it does give you is a filing date — and only for what you actually wrote down in it. That distinction is the single most expensive misunderstanding in early-stage patenting, and most articles about provisionals never mention it.

Here’s what a provisional really does, what it costs, the deadline that governs everything, and the mistakes that cost founders their priority date years after they think they’re safe.

What a provisional patent application actually does

Three things, and that’s the complete list.

It establishes a filing date with the USPTO for the invention it describes.

It lets you say “Patent Pending” in connection with the invention while the application is pending.

It starts a 12-month clock to file a non-provisional application if you want to pursue an actual patent.

Now the things it does not do, all of which get claimed somewhere online:

It gives you no rights against anyone. There’s no right to exclude until a patent issues. A provisional confers none.

You cannot sue on it. Infringement requires an issued patent with claims. A provisional has no claims — 35 U.S.C. 111(b)(2) says none are required — is never examined, and never issues. There’s nothing to assert.

It is never examined. Under 35 U.S.C. 111(b)(8), provisionals aren’t subject to examination. Nobody at the USPTO reads it to tell you whether it’s any good. This is more dangerous than it sounds, and we’ll come back to it.

It cannot be extended or revived. Under 35 U.S.C. 111(b)(5), a provisional is regarded as abandoned 12 months after filing and is not subject to revival after that period.

What a provisional actually protects — and why thin filings fail

This is the part to read twice.

Under 35 U.S.C. 119(e)(1), a later application gets the provisional’s filing date only for an invention “disclosed in the manner provided by section 112(a)” in that provisional — and only “as to such invention.”

In plain terms: the provisional has to describe and enable the invention well enough that someone skilled in the field could make and use it. Whatever you didn’t describe adequately doesn’t get the early date.

And it’s tested claim by claim. MPEP 211.05 states it directly: if a claim in the non-provisional isn’t adequately supported by the written description of the provisional, that claim doesn’t get the benefit of the provisional’s filing date.

What that costs in practice. In New Railhead Manufacturing v. Vermeer Manufacturing (Federal Circuit, 2002), the provisional failed to describe an angle limitation that ended up in the claims. The claim lost the provisional’s filing date. With the later date, the inventor’s own prior commercial use became prior art — and the patent was held invalid.

Here’s what makes this genuinely dangerous rather than merely technical: because provisionals are never examined, nobody tells you yours was thin. You file it, you feel protected, and you find out years later during prosecution or litigation when someone challenges your priority date.

So the honest framing is this. A provisional doesn’t give you a date for your invention. It gives you a date for what you wrote down. A two-page provisional does not cover an invention that takes twenty pages to explain.

The 12-month deadline, and the narrow exception nobody explains properly

You have 12 months from the provisional’s filing date to file a non-provisional application. Miss it and the provisional is abandoned by operation of law.

Most articles stop there and say there are no exceptions. That isn’t correct.

Under 35 U.S.C. 119(e)(1) and 37 CFR 1.78(b), if you file the non-provisional after 12 months but within 14 months, you can petition to restore the benefit of the provisional. The petition needs three things:

A reference to the provisional in an Application Data Sheet, identifying it by application number. A statement that the delay in filing within the 12-month period was unintentional. And the petition fee under 37 CFR 1.17(m)(3) — currently $2,260 for a large entity, $904 small entity, $452 micro entity.

But read this before you rely on it. That restoration is US-only. Under PCT Rule 49ter.1(b), a restoration granted on the “unintentional” standard is effective only where national law uses that standard or something more favorable. The European Patent Office applies a stricter “due care” test. So a founder who restores at month 13 in the US can still lose the priority date in Europe entirely.

Treat 12 months as the real deadline. Fourteen months is an expensive US-only emergency exit that may cost you your international position.

One more distinction that gets constantly conflated: the 14-month petition restores a benefit claim in your later application. It does not extend or revive the provisional itself. Those are different things.

What it costs

The USPTO filing fee for a provisional application under 37 CFR 1.16(d) is $325 for a large entity, $130 for a small entity, and $65 for a micro entity, per the fee schedule effective 19 January 2025, last revised 14 August 2026. Fees change, so check the current schedule before filing.

Two cautions about that number.

It’s the filing fee alone. It doesn’t include drawings, attorney time, or the much larger non-provisional fees — basic filing, search and examination — due twelve months later. Anyone presenting $65 as “the cost of protecting your invention” is describing the deposit, not the purchase.

And small and micro entity status have real eligibility conditions, including gross income and prior filing limits for micro entity status under 37 CFR 1.29. Don’t assume you qualify.

The cheapness of a provisional is exactly what makes the thin-filing trap so common. It’s affordable enough to file something rough, and the consequences don’t surface for years.

“Patent Pending”: what you can say, and when you have to stop

Once your provisional is on file, using “Patent Pending” is entirely proper. The USPTO says so directly.

The question nobody answers is what happens afterwards.

Under 35 U.S.C. 292(a), it’s prohibited to use “patent pending” on an article, or in advertising connected to it, when no application has been made or, if made, is not pending — where done for the purpose of deceiving the public. The penalty is up to $500 per offense, and in Forest Group v. Bon Tool the Federal Circuit read “offense” as meaning per falsely marked article.

Three things make this less alarming than it first sounds, and you should know all three:

It requires intent to deceive. Under Pequignot v. Solo Cup, false marking creates only a rebuttable presumption of intent, and good faith rebuts it. Carelessness isn’t enough.

Private bounty suits are gone. The America Invents Act removed the old qui tam provision. Only the United States can sue for the statutory penalty, and a private party needs to show actual competitive injury and recovers only its own damages.

But the expired-patent safe harbor does not help you. Section 292(c) protects marking related to a patent that covered the product and has expired. A lapsed application is not an expired patent. That defense isn’t available.

So: leaving “Patent Pending” on your packaging after your provisional lapses is a technical violation, unlikely to be enforced against you, not covered by the safe harbor, and completely avoidable. When the application stops being pending, remove the marking — from packaging, the website, and the sell sheet you forgot about.

Disclosure, the grace period, and why filing first matters more than you think

This is where founders lose international rights without realizing it.

The US has a grace period, but a narrow one. Under 35 U.S.C. 102(b)(1), a disclosure made one year or less before your effective filing date isn’t prior art against you if the disclosure came from you, or from someone who got it from you.

Note what that doesn’t cover. It’s not a general one-year amnesty. If a third party independently discloses the same subject matter during that year, it’s still prior art against you. The shield only protects against disclosures traceable back to you.

Most of the world has no equivalent. Under Article 54(2) of the European Patent Convention, the state of the art is everything made available to the public before the filing date — with no carve-out for the applicant’s own disclosure. The narrow exceptions in Article 55 cover evident abuse and display at officially recognized international exhibitions, and they run from the filing date rather than the priority date. Publishing a paper, launching a product, running a crowdfunding campaign or demoing at an ordinary trade show is not covered.

So a founder who demos publicly and files a provisional two months later has preserved their US position and destroyed their European one. File before you disclose is the only rule that works everywhere.

And the foreign clock runs from the provisional too. Under Article 4 of the Paris Convention, the 12-month priority period for filing abroad runs from the date of your first filing — which is the provisional. That’s why the 12-month date is simultaneously your US deadline and your international one.

Is a provisional confidential?

Yes, and then eventually no.

Provisionals are exempt from 18-month publication under 35 U.S.C. 122(b)(2)(A)(iii). A provisional is never published as such.

But under 37 CFR 1.14, the file contents of an unpublished application become available on request once its benefit is claimed in an application that has published or issued as a patent. So the moment your non-provisional publishes — typically around 18 months after the provisional’s filing date — your provisional becomes retrievable.

Two practical consequences. A provisional you file and abandon without ever claiming its benefit stays confidential indefinitely. And a provisional whose benefit you do claim will eventually be readable by your competitors, including the parts that were thin. It is not a place to hide anything, and it is not a substitute for a trade secret.

Five things about provisionals that are commonly said and wrong

“I have a provisional patent.” There’s no such thing. Only a provisional application. It’s the clearest signal that a source doesn’t know the subject.

“I’ll file another provisional to extend my date.” You can’t. Under 35 U.S.C. 111(b)(7), a provisional cannot claim priority from or benefit of any earlier application. A second provisional gives new material a new, later date. Your original 12-month clock keeps running regardless.

“I can revive it if I miss the deadline.” Not the provisional itself — 111(b)(5) rules that out explicitly. The 14-month petition restores a benefit claim in a later-filed application, which is a different thing.

“It’s cheap, so I’ll file something rough and improve it later.” You cannot add material later and keep the early date. New matter gets the new date. The USPTO warns specifically that some invention promotion firms misuse the provisional process and leave inventors with no patent at all.

“It protects me at the trade show.” In the US, if it describes what you’re showing. Not in Europe or most of the world, where your public disclosure has already destroyed novelty before you file.

How Inventornest works with founders on this

We’re a product development team, not a law firm. We provide patent services through expert patent attorneys engaged according to the product and relevant jurisdiction. What we do is the part that determines whether a provisional is worth anything: helping you describe your invention well enough to be worth filing.

The enablement requirement in 35 U.S.C. 112(a) asks whether someone skilled in the field could make and use the invention from your description. That’s an engineering documentation problem before it’s a legal one. Detailed drawings, dimensioned assemblies, material choices, tolerances, circuit topology, firmware behavior, the alternatives you considered — that’s what turns a two-page sketch into a filing that holds up.

Which is also why building and patenting aren’t really in competition. A prototype teaches you what your invention actually is, and you can’t describe what you haven’t figured out. The constraint is simply that you shouldn’t publicly disclose before filing.

If you’re working out what to document before talking to a patent attorney, or deciding the order to do things in, book a consultation. Our product prototyping services cover the builds and documentation that support a filing, and it’s worth reading whether a patent or a prototype comes first if you’re deciding where to start.

Provisional patent applications: frequently asked questions

What is a provisional patent application?

A filing under 35 U.S.C. 111(b) that establishes a filing date with the USPTO for the invention it describes and lets you use “Patent Pending” while it’s pending. It’s never examined, never issues as a patent, and gives you no rights to enforce against anyone. It starts a 12-month clock to file a non-provisional application.

How long does a provisional patent application last?

Twelve months from the filing date, after which it’s abandoned by operation of law and cannot be revived. If you file the non-provisional within 14 months you can petition to restore the benefit under 37 CFR 1.78(b), but that restoration is US-only and may not preserve your foreign priority.

How much does a provisional patent application cost?

The USPTO filing fee is $325 large entity, $130 small entity, $65 micro entity, per the fee schedule effective January 2025 and last revised August 2026. That’s the filing fee alone — it excludes drawings, attorney time, and the substantially larger non-provisional fees due twelve months later.

Does a provisional patent application protect my idea?

It gives you a filing date for what the application actually describes and enables, and nothing more. It confers no right to stop anyone from making, using or selling anything. Subject matter you didn’t describe adequately gets no benefit from the filing date.

Can I sue someone with a provisional patent application?

No. Infringement requires an issued patent with claims. A provisional has no claims, is never examined, and never issues, so there is nothing to enforce.

What happens if I miss the 12-month deadline?

The provisional is abandoned and cannot be revived. However, if you file the non-provisional within 14 months of the provisional’s filing date, you can petition to restore the benefit — requiring a reference in an Application Data Sheet, a statement that the delay was unintentional, and a fee of $2,260, $904 or $452 depending on entity size. This restores your US benefit claim only.

Can I keep filing provisionals to extend my protection?

No. Under 35 U.S.C. 111(b)(7) a provisional cannot claim benefit of an earlier application. A second provisional gives new material a later date and does not move your original date forward.

Can I use “Patent Pending” after my provisional expires?

You shouldn’t. Section 292(a) prohibits using the term when an application is not pending, where done to deceive the public, and the safe harbor for expired patents doesn’t apply to a lapsed application. Enforcement requires proof of intent to deceive and either government action or a competitor showing competitive injury — but it’s avoidable, so remove the marking when the application lapses.

Should I file before showing my product publicly?

Yes, if foreign rights matter to you. The US grace period under 35 U.S.C. 102(b)(1) gives you one year after your own disclosure, but Europe and most other jurisdictions apply absolute novelty, so a public disclosure before filing permanently destroys novelty there.

Is my provisional application confidential?

Provisionals are never published themselves. But once you claim the benefit of one in an application that publishes or issues, the provisional becomes publicly available under 37 CFR 1.14 — typically around 18 months after you filed it.

Last reviewed September 2026. Fees and regulations change — verify current figures with the USPTO before filing. This article is general information and not legal advice.