A provisional patent application lasts exactly 12 months from its filing date — and that period cannot be extended. Per 35 U.S.C. 111(b)(5) and USPTO guidelines, the application automatically abandons by operation of law on day 365, with no notice from the USPTO and no possibility of revival. What most inventors don’t fully appreciate is that this 12-month window isn’t just a deadline to survive — it’s the period during which the quality of your technical disclosure either locks in or limits the scope of protection you can ultimately obtain.
Having reviewed thousands of provisional applications as USPTO patent examiners, our team at IP Boutique Law knows exactly what separates a provisional that holds up under scrutiny from one that quietly undermines your future claims.
Last updated: March 2026
The 12-month provisional patent clock: what the USPTO says
A provisional patent application has a pendency period of 12 months from its filing date. The USPTO is unambiguous on this: the 12-month period cannot be extended, and the application “shall not be subject to revival” once it lapses (35 U.S.C. 111(b)(5), codified in MPEP § 201.04).
There is one narrow exception — if the 12-month deadline falls on a Saturday, Sunday, or a federal holiday in Washington D.C., the deadline moves to the next succeeding business day.
The USPTO will not send you a reminder as the deadline approaches. The application simply abandons automatically. This is a harder stop than most legal deadlines — there is no grace period, no request for extension, and no petition to revive after the fact. Under 37 CFR 1.78, there is a provision to restore the benefit of a provisional application if the non-provisional is filed within 14 months (rather than 12) and the delay was unintentional, but this is a narrow petition process with its own fees and requirements — not a standard extension.
One technical detail worth knowing: there is no such thing as a “provisional patent.” The USPTO issues no patent from a provisional filing. The application establishes a priority date and grants “patent pending” status, but examination never occurs. A patent can only result from a non-provisional application filed and examined on its merits.
What the 12-month window is actually for
The year a provisional buys you is not passive waiting time. It is the period during which strategic decisions about your invention’s commercial and legal future should be made — and acted on.
- Refine the invention. You can continue developing, testing, and improving your invention during the provisional period. Critically, subject matter you add after the provisional filing date will not be entitled to that earlier priority date. If your invention evolves significantly, you need to carefully evaluate whether to file a continuation of the provisional (a second provisional covering new subject matter) or build the additions directly into your non-provisional.
- Assess commercial viability. The provisional year is when many inventors seriously evaluate whether pursuing a full patent makes financial sense. The cost of a non-provisional patent application is substantially higher than a provisional — both in attorney fees and USPTO filing fees. Using this window to gauge market interest, talk to potential licensees, or test manufacturing feasibility is a legitimate and common strategy.
- Conduct a thorough patent search. A professional patent search during the provisional period — rather than after — lets you identify prior art that may affect claim strategy before you commit to the expense of a full application. Examiners see many non-provisional applications arrive without any prior art analysis having been done. The result is often weak, narrowly-drafted claims that don’t hold up in the field.
- File internationally. The provisional filing date starts the clock under the Paris Convention. You have 12 months from that date to file in foreign countries and claim priority to your U.S. provisional. Miss that window and you lose the ability to claim your original filing date in those jurisdictions. For inventors targeting markets in Europe, Asia, or Latin America, this deadline runs parallel to the U.S. non-provisional deadline and demands equal attention. See the USPTO’s international patent cooperation guidance for country-specific requirements.
Your provisional patent timeline: month by month
The 12 months tend to disappear faster than inventors expect. Here is a realistic breakdown of how the year should be used.
| Period | Priority actions |
|---|---|
| Months 1–3 | Complete invention testing; begin prior art research; evaluate international filing strategy |
| Months 4–8 | Commission professional patent search; decide on claim strategy; engage attorney to draft non-provisional |
| Months 9–11 | Non-provisional drafting and inventor review; finalize claims and drawings; prepare filing |
| Month 12 | Target filing by day 335-345 at the latest — not day 365 |
That last point matters more than it sounds. Filing at the very end of the 12-month window leaves no room for technical problems with USPTO’s electronic filing system, unexpected questions from your attorney requiring inventor input, or business disruptions. Our team targets month 11 as the practical deadline for non-provisional filing — not month 12. The statutory deadline is absolute.
A separate milestone runs in parallel for international filers: the Paris Convention deadline for foreign national filings is also 12 months from the provisional filing date — the same day as the U.S. non-provisional deadline. If you plan to file a PCT (Patent Cooperation Treaty) application, that 12-month deadline governs as well. These are not sequential deadlines — they converge on the same date.
What happens when a provisional patent application expires
There are three distinct scenarios depending on what happened during the 12-month period.
Scenario 1: You filed a non-provisional on time.
The provisional fulfills its purpose. Your non-provisional claims the benefit of the provisional’s filing date under 35 U.S.C. 119(e), and examination proceeds. The provisional itself is abandoned — that is expected and correct. The priority date it established travels with your non-provisional throughout prosecution.
Scenario 2: The provisional expired after public disclosure.
This is the scenario with the most severe consequences. If you publicly disclosed, sold, offered for sale, or otherwise made your invention available to the public during the provisional period — and then let the provisional lapse without filing a non-provisional — you may have permanently forfeited your right to patent the invention. The USPTO is explicit: under 35 U.S.C. §§ 102(a)(1) and (b)(1), a public disclosure combined with a missed deadline can eliminate patentability entirely, not just delay it. This is not a recoverable situation.
Scenario 3: The provisional expired with no prior public disclosure.
If you never publicly disclosed the invention and your provisional lapsed, you may be able to re-file a new provisional application. However, you can only claim priority to the new filing date — not the original one. Any patent issued from the re-filed application will be measured against prior art up to the new filing date, not your original date. If competitors filed during the gap between your original provisional and re-filing, their applications could anticipate your claims.
Abandoned provisionals are not published by the USPTO. The content remains confidential. If you decide not to pursue the patent at all, competitors will not learn what you disclosed — which is a meaningful protection in some trade secret contexts.
When the 12 months don’t protect you as much as you think
There is a less-discussed risk inside the 12-month window that trips up many inventors: the assumption that converting to a non-provisional automatically preserves full priority for everything you want to claim.
It does not.
Under 35 U.S.C. 112(a), a non-provisional application is only entitled to the benefit of its provisional’s filing date for subject matter that was adequately disclosed in the provisional — not for new subject matter added during drafting of the non-provisional. Examiners evaluate this directly during examination.
If your non-provisional claims an embodiment, feature, or technical element that was not present in the provisional, the examiner will assign a later effective date to those claims — potentially making them vulnerable to intervening prior art.
We see this play out regularly. An inventor files a reasonable provisional, spends the year improving the product, and arrives at the non-provisional stage wanting to claim the improved version. If the improvements weren’t in the provisional, they don’t get the earlier priority date. The original filing date protected only what was originally disclosed.
This is why the quality of your provisional matters as much as whether you filed on time. A provisional that describes your invention at the idea stage but not with the technical depth required to support claims leaves you exposed even if you convert within 12 months. At IP Boutique Law, we draft provisionals with the non-provisional in mind — because examiners look at the provisional’s disclosure when determining whether claims in the non-provisional are entitled to priority. We’ve seen both sides of that evaluation.
FAQs
The application automatically abandons 12 months after its filing date by operation of law — the USPTO sends no notice. If you publicly disclosed the invention during the provisional period and miss the deadline, you may permanently lose the right to patent that invention under 35 U.S.C. § 102. If there was no public disclosure, re-filing a new provisional is possible, but priority resets to the new filing date, not the original.
No. The 12-month pendency period is statutory and cannot be extended. There is a narrow provision under 37 CFR 1.78 to restore the benefit of a provisional if a non-provisional is filed within 14 months and the delay was unintentional, but this requires a petition with associated fees and is not a guaranteed remedy. It is not a standard extension.
Yes, if you have not made any public disclosure of the invention in the prior 12 months. The re-filed provisional establishes a new priority date — you cannot recover the original filing date. Any prior art that emerged between your original filing and re-filing is now in play against your claims.
Provisional applications are never examined or “approved” by the USPTO. They are administrative placeholders that establish a priority date and grant patent pending status. No action is taken by the USPTO on the provisional itself — examination only begins after you file a non-provisional application claiming the provisional’s benefit.
A U.S. provisional application establishes a filing date that can be used as the basis for international filings under the Paris Convention, but only if those filings are made within 12 months of the provisional filing date. The provisional itself provides no direct protection outside the U.S. You must affirmatively file in each country (or through a PCT application) within that 12-month window to extend the priority date internationally.
A provisional application requires no formal claims, no oath or declaration, and is never examined — it establishes a priority date and expires in 12 months. A non-provisional patent application is a complete application with formal claims that undergoes examination by a USPTO examiner and can result in an issued patent with a 20-year term. The provisional’s filing date does not count toward the 20-year patent term — filing a provisional effectively adds up to one year of patent protection by delaying the start of that term.
Start the provisional process with the right foundation
A provisional patent application is only as valuable as the technical disclosure inside it and the strategy surrounding its conversion. The 12-month window is real, firm, and unforgiving — but the more common failure we see is not a missed deadline, it is a provisional that was drafted too narrowly to support the claims an inventor ultimately wants to pursue.
IP Boutique Law is a patent and intellectual property firm in Washington, D.C. with 25+ years of USPTO examiner experience. Our team handles patent drafting, prosecution, trademark registration, design patents, provisional applications, ex parte reexamination, and patent reissue across chemical, biochemical, electrical, and mechanical fields. We serve inventors and companies in the U.S. and internationally, bringing insider examiner knowledge to every stage of the patent process.
If you have a provisional application pending — or are considering filing one — contact us to discuss how to structure your 12-month window to maximize what your non-provisional can ultimately claim. Reach us at +1 202 773 9579 or contact@ipboutiquelaw.com to schedule a consultation.
Reviewed by Carlos López, patent attorney and former USPTO examiner with 25+ years of IP experience.