Patent Priority and International Filing Checklist: Provisionals, PCT Deadlines, and Foreign Filing Licenses

By Casey Scott McKay · 2025-09-11

Priority is a chain of filings and deadlines, and almost every loss in this area is a calendar failure rather than a legal one. This checklist runs the chain in fourteen phases: screen the disclosures, verify the foreign filing license, draft a provisional that actually preserves something, build the priority map, hit the twelve-month decision, file and prosecute the international application, select countries at month twenty-four, enter the national phase, and then manage translations, divisionals, and annuities for twenty years. Each box gives the reason, the authority, and the trap. It marks the deadlines that cannot be extended and separates the losses that can be recovered from the ones that cannot. A worked matter runs throughout, and the companion article and guide supply the doctrine and the strategy.

IP and Technology > Patent Counseling Transactions | Checklist | Published 11 September 2025 - Updated 14 June 2026 | Casey Scott McKay - marksy.us

Summary. Priority is a chain of filings and deadlines, and almost every loss in this area is a calendar failure rather than a legal one. This checklist runs the chain in fourteen phases: screen the disclosures, verify the foreign filing license, draft a provisional that actually preserves something, build the priority map, hit the twelve-month decision, file and prosecute the international application, select countries at month twenty-four, enter the national phase, and then manage translations, divisionals, and annuities for twenty years. Each box gives the reason, the authority, and the trap. It marks the deadlines that cannot be extended and separates the losses that can be recovered from the ones that cannot. A worked matter runs throughout, and the companion article and guide supply the doctrine and the strategy.

Keywords: priority checklist, provisional application, foreign filing license, absolute novelty, twelve month deadline, thirty month deadline, PCT national phase, priority map, benefit claim, cross-reference, written description support, country selection, translation review, annuities, divisional abroad, disclosure log, restoration of priority, co-pendency, effective filing date, portfolio budget

How to use this checklist

| Phase | What it covers | When | |---|---|---| | 1 | Screen the disclosures | Before anything | | 2 | Verify the foreign filing license | Before filing abroad | | 3 | Draft a provisional that preserves something | Before any external event | | 4 | Build the priority map | At the second filing | | 5 | Hit the twelve-month decision | Month 12 | | 6 | File the international application | Month 12 | | 7 | Work the search report | Months 16–24 | | 8 | Select countries | Month 24 | | 9 | Prepare for entry | Months 27–29 | | 10 | Enter the national phase | Month 30 | | 11 | Prosecute abroad | Years 3–6 | | 12 | Handle grant and validation | On allowance | | 13 | Manage annuities | Years 2–20 | | 14 | Review annually | Ongoing |

The deadlines that cannot be extended appear in Phases 5, 10, and 14, and are marked [Gate]. The two that can never be recovered — continuation co-pendency and a pre-filing foreign disclosure — appear in Phases 1 and 14.

The matter. Brightwater Sensing filed a provisional in March, demonstrated at a trade show in June, and engaged counsel in the following January to "file internationally." The first two phases of this checklist determined what was still possible, and the answer was not what the founders expected.

Phase 1. Screen the disclosures

[ ] [Gate] Ask what has been published, demonstrated, offered, or sold, and on what dates.
- Why. It determines whether foreign rights exist before any money is spent.
- Authority. 35 U.S.C. § 102(a)(1).
- Trap. Asking only the inventors. Sales, marketing, and business development hold dates engineers do not know.
[ ] Apply the absolute-novelty rule to each event.
- Why. Most jurisdictions have no general grace period, so a public disclosure before the priority date destroys patentability there.
- Authority. The U.S. grace period at 35 U.S.C. § 102(b)(1) is domestic and does not travel.
- Trap. "You have a year," said without the geographic qualification. The most expensive sentence in this practice.
[ ] Check the narrow exceptions.
- Why. Some offices excuse disclosure at an officially recognized international exhibition, or disclosure resulting from an evident abuse in relation to the applicant. Formal, narrow, and usually requiring a declaration with the application.
- Trap. Relying on an exhibition exception without the official designation.
[ ] Record every event with a date and the artifact.
- Why. Establishing grace-period protection is evidentiary, and the proof is far easier now than in a declaration three years on.
- Trap. A link to a page that has since changed.
[ ] Tell the client plainly what survives, before quoting the work.
- Trap. Filing abroad on an invention already disclosed, which is spending money on rights that do not exist.

Brightwater, Phase 1. The June trade show demonstration was the first public disclosure. The March provisional predated it — which preserved everything, but only for subject matter the provisional described. Phase 3 became the critical question.

Phase 2. Verify the foreign filing license

[ ] Determine where the invention was made.
- Why. An invention made in the United States generally requires authorization before an application is filed abroad.
- Authority. 35 U.S.C. § 184.
- Trap. A distributed engineering team where part of the conception happened domestically.
[ ] Confirm the license was granted, usually on the U.S. filing receipt.
- Trap. Filing abroad first through a foreign parent's counsel without checking.
[ ] Where no U.S. application exists, obtain a petition for a license before filing abroad.
- Authority. Consequences of unlicensed foreign filing at 35 U.S.C. § 185, which can include invalidity of a later U.S. patent.
[ ] Record the license status in the file.

Phase 3. Draft a provisional that preserves something

[ ] [Gate] Describe the mechanism, not the benefit.
- Why. A provisional preserves what it describes, judged under the written description and enablement standards.
- Authority. 35 U.S.C. § 111(b); support judged under 35 U.S.C. § 112(a); benefit under 35 U.S.C. § 119(e).
- Trap. A pitch deck converted to PDF, which buys a date for a document rather than for an invention.
[ ] Describe alternatives for every element.
- Why. Unwritten alternatives are unclaimable forever, and this is the cheapest place to capture them.
[ ] Recite ranges at broad, intermediate, and specific levels.
- Trap. One value and no range, which forecloses every later claim to a different one.
[ ] Include a figure and a flowchart for any process.
[ ] Include draft claims even though none are required.
- Why. Claims force the drafter to identify what is being protected and immediately reveal whether the specification supports it.
- Trap. Skipping them because they are optional.
[ ] File a series as development proceeds.
- Why. Each captures what exists at its date, and a single non-provisional can claim benefit of all of them.
- Trap. One early provisional relied on for a year of subsequent work.
[ ] Diary the twelve-month conversion the day it is filed.

Brightwater, Phase 3. The March provisional was a six-page description of the sensing element with two figures and no claims. It supported claims to the element and the calibration approach. It did not describe the enclosure geometry the company later considered its commercial differentiator, and no filing before June did — so that feature was foreclosed abroad.

Phase 4. Build the priority map

[ ] One row per application: filing date, benefit claims, resulting effective filing date.
- Authority. 35 U.S.C. § 100(i).
- Trap. Building it at the fifth filing rather than the second.
[ ] Add a claim-level column.
- Why. Within one application, different claims can carry different effective filing dates depending on what the earliest disclosure supported. Partial entitlement is normal.
- Trap. A family where nobody can say what date any given claim gets.
[ ] Verify every cross-reference against the filed papers.
- Authority. 35 U.S.C. § 120 requires a specific reference.
- Trap. A defective or omitted benefit claim, which breaks the chain silently.
[ ] Record which regime governs each member.
- Why. Applications with an effective filing date before 16 March 2013 run under the prior statute, with the antedating route under 37 C.F.R. § 1.131 available.
- Trap. Applying the current analysis to a pre-AIA family member.
[ ] Track foreign counterparts on the same map.

Phase 5. Hit the twelve-month decision

[ ] [Gate] Compute the twelve-month deadline from the first filing anywhere.
- Authority. 35 U.S.C. § 119(a) for Paris priority; 35 U.S.C. § 119(e) for provisional conversion.
- Trap. Computing from the U.S. non-provisional rather than from the provisional.
[ ] Choose the route deliberately.
- Why. Direct Paris filings, a PCT application, a PCT plus one direct filing, a regional route, or domestic only.
- Trap. Defaulting to the PCT without considering whether the countries are already known, or defaulting to domestic-only by inaction.
[ ] Where the route is domestic only, decide about non-publication deliberately.
- Authority. 35 U.S.C. § 122(b). It keeps the application secret until grant and permanently forfeits foreign rights if certified and foreign filing later occurs.
[ ] Confirm the priority document supports the claims being pursued.
- Trap. Filing abroad on claims the priority document never described.

Phase 6. File the international application

[ ] File with the appropriate receiving office, claiming priority.
- Authority. 35 U.S.C. § 351; 35 U.S.C. § 363; priority right at 35 U.S.C. § 365.
[ ] Choose the International Searching Authority deliberately.
- Why. More than one may be available, and they differ in search quality, cost, timing, and reception by particular national offices.
- Trap. Accepting the default.
[ ] Designate all states.
- Why. It costs nothing incremental and the selection happens at national phase.
[ ] Get the claims right at filing, since the search responds to them.

Phase 7. Work the search report

[ ] Read the international search report and written opinion as a filing decision input.
- Why. A poor opinion is a reason to reconsider the country list before spending on national phases.
[ ] Amend the claims where the report warrants it.
- Why. Amendment of claims is available once after the search report, and further amendment during preliminary examination.
[ ] Decide about international preliminary examination.
- Trap. Ordering it reflexively where it will not change any national-phase decision.
[ ] [Gate] Feed the cited art into every co-pending domestic application.
- Authority. 37 C.F.R. § 1.56; mechanics at 37 C.F.R. § 1.97.
- Trap. A search report that never crosses the desk of U.S. counsel. See Prior Art and Patentability Checklist.

Phase 8. Select countries at month twenty-four

[ ] Score each candidate on revenue, manufacturing, enforceability, competitive presence, licensing, and cost.
- Why. This is the decision the PCT bought, and it is the one with the largest effect on total spend.
- Trap. Making it at month twelve, which pays for the option and does not use it.
[ ] Weigh manufacturing jurisdictions properly.
- Why. A patent at the point of manufacture stops goods before they scatter into distribution.
- Trap. Ranking by revenue alone because revenue is visible.
[ ] Cut the tail.
- Why. Portfolios filed in eight or more countries typically abandon half within five years, having paid entry, translation, and early annuities for nothing.
- Trap. Covering the map.
[ ] Build the one-page per-country sheet: entry cost and twenty-year cost.
- Why. The ranking usually changes when the second column appears.
- Trap. Budgeting entry only, which produces abandonment by lapse.
[ ] Record the countries not entered, and why.
- Why. The question is asked in diligence years later.

Phase 9. Prepare for entry

[ ] Appoint local counsel a month early, not on the deadline.
[ ] Trim claims to each office's fee thresholds.
- Trap. Excess claim and multiple-dependency fees paid unnecessarily.
[ ] Adapt claim format to local practice.
- Why. Two-part form, method-of-treatment restrictions, and software claim formats all differ.
[ ] [Gate] Commission translations with review time.
- Why. A translation error in the claims is a permanent scope error discovered by an opponent years later.
- Trap. A translation delivered and filed the same day.
[ ] Consider unity of invention per office.
- Trap. A claim set that survives unity review in one office and is split in another, generating divisional costs nobody budgeted.

Phase 10. Enter the national phase

[ ] [Gate] Diary the deadline per office.
- Why. Thirty months from the earliest priority date in most offices, thirty-one in some, and a few differ.
- Authority. 35 U.S.C. § 371 for U.S. national stage entry.
- Trap. Treating it as uniform.
[ ] Treat it as unforgiving.
- Why. Some offices permit late entry on a showing and a fee; many do not, and the answer is jurisdiction-specific and time-sensitive.
[ ] Confirm the priority claim is properly made in each office.
[ ] Record assignments where the office requires it for the applicant to be recognized.
- Authority. 35 U.S.C. § 261 domestically; local requirements vary.

Phase 11. Prosecute abroad

[ ] Expect divergent claim scope and plan for it.
- Why. Inventive-step standards, added-matter practice, and subject-matter exclusions all differ.
[ ] Check added-matter practice before every amendment.
- Trap. An amendment routine domestically and refused abroad, occasionally trapping the applicant between an unremovable amendment and an invalid claim.
[ ] Use allowances elsewhere to accelerate.
- Why. Prosecution highway mechanisms advance counterparts out of turn.
[ ] Route every foreign office action to domestic counsel.
- Authority. 37 C.F.R. § 1.56.
[ ] Coordinate arguments across offices.
- Trap. Inconsistent characterizations of the same reference in different jurisdictions, which arise because each is handled separately.
[ ] Keep one person accountable for the family.

Phase 12. Handle grant and validation

[ ] Budget grant fees and final translations, which are substantial.
[ ] Make validation decisions in regional systems deliberately.
- Why. Per-state cost makes this another country-selection moment rather than a formality.
[ ] Evaluate unitary effect options where available.
- Why. They change the cost structure and the enforcement forum for the life of the right.
[ ] Diary post-grant opposition windows.
- Why. They are short, they exist in several systems, and they are a risk to the patentee and an opportunity against a competitor.

Phase 13. Manage annuities

[ ] Build the schedule per country to expiry, at entry.
- Why. Annuities are the largest lifetime cost, they escalate, and they begin during prosecution in several jurisdictions.
- Trap. Seeing only the first payment.
[ ] Assign responsibility explicitly — service, agent, or client.
- Trap. Everyone assuming someone else pays.
[ ] Review annually against the business.
[ ] Abandon deliberately rather than by non-payment.
- Why. A portfolio pruned on purpose keeps the right patents; one pruned by lapse loses whichever happened to fall due during a distracted quarter.

Phase 14. Review annually, and know what cannot be recovered

[ ] [Gate] Confirm continuation co-pendency in every domestic family.
- Authority. 35 U.S.C. § 120.
- Trap. Not recoverable. This is not an abandonment to be revived; the family simply closed.
[ ] Confirm divisional windows abroad.
- Why. Foreign systems have no general equivalent of the U.S. continuation, and the windows are shorter and stricter.
- Trap. Also generally not recoverable.
[ ] Distinguish recoverable losses from permanent ones.
- Why. A missed office action response or issue fee is revivable on a petition and a fee. A missed provisional conversion or Paris deadline may have narrow restoration routes. A closed family and a pre-filing foreign disclosure have none.
- Authority. 35 U.S.C. § 133 for reply deadlines.
[ ] Re-verify country list against the current business.
[ ] Report one page per family: countries, cost last year, cost next year, recommendation.
- Why. It is what keeps an international portfolio funded.

Brightwater, outcome. The March provisional preserved the sensing element and calibration claims worldwide. The enclosure geometry, first disclosed at the June trade show with nothing on file describing it, was foreclosed in absolute-novelty jurisdictions and remained available in the United States within the grace period. The company filed a PCT at month twelve, cut its country list from nine to three at month twenty-four, and now files a provisional before every external event as a standing rule.

Phase 15. The deadline reference

| Deadline | Runs from | Length | Extendable? | What is lost if missed | |---|---|---|---|---| | Provisional conversion | Provisional filing | 12 months | Narrow restoration only | The priority date | | Paris Convention priority | First filing anywhere | 12 months | Narrow restoration only | Foreign priority | | PCT filing | Earliest priority | 12 months | No | The PCT route entirely | | Article 19 claim amendment | Search report transmittal | Short | No | One amendment opportunity | | Preliminary examination demand | Per the rules | Short | No | The second written opinion | | National phase entry | Earliest priority | ~30 months, varies | Per office, often not | Rights in that country | | Office action reply, U.S. | Action mailing | 3 months, to 6 max | To 6 months only | Abandonment, revivable | | Issue fee, U.S. | Notice of allowance | 3 months | No | Abandonment of an allowed case | | Continuation co-pendency | — | Until parent issues | No | The entire family, permanently | | Divisional, U.S. | — | Until parent issues | No | Non-elected claims, permanently | | Divisional, foreign | Per office | Shorter, varies | Usually not | The divisional, permanently | | Post-grant opposition | Grant publication | Short, varies | No | The central challenge route | | Annuities | Per office schedule | Varies | Surcharge window | The patent lapses |

[ ] Mark the rows with "No" differently in the docket.
- Trap. A docketing system with one reminder profile for every deadline.
[ ] Docket the deadlines with no incoming paper separately.
- Why. Co-pendency and divisional windows are not on any document, so nothing arrives to prompt them.
- Authority. 35 U.S.C. § 120; 35 U.S.C. § 121.
[ ] Run a monthly review independent of incoming correspondence.
- Why. It is the only way to catch the promptless deadlines.

Phase 16. Cost, and where it accumulates

| Item | Relative cost | When | |---|---|---| | Disclosure screen and priority verification | Negligible | Before anything | | Provisional, drafted properly | Low | Before any external event | | U.S. non-provisional | Substantial | Month 12 | | PCT filing and search | Moderate | Month 12 | | Article 19 or 34 amendments | Low | Months 18–24 | | National phase entry, per country | Moderate to high | Month 30 | | Translation, per country | Often the largest entry item | Month 30 | | Prosecution abroad, per country | Moderate to high | Years 3–6 | | Grant, publication, validation | Moderate | On allowance | | Annuities, per country, to expiry | Largest lifetime cost | Years 2–20 |

Three observations.

Entry is a fraction of lifetime. Clients who budget only for entry abandon by lapse, and lapse loses whichever patents happened to fall due during a distracted quarter rather than the ones worth losing.

Translation and annuities dominate, and both scale with the number of countries. Which makes country selection at Phase 8 the single largest cost lever in the entire chain — larger than drafting, larger than prosecution, larger than anything a practitioner does at the desk.

The cheapest phases are the first three. A disclosure screen costs nothing, a foreign filing license check costs nothing, and a properly drafted provisional costs a small fraction of the rights it preserves. Every failure they prevent is a failure that cannot be repaired at any later price.

Phase 17. Special situations

Four postures that change the sequence.

University and research filings

[ ] Tie a provisional to every manuscript submission as a standing rule.
- Why. Publication is the institutional purpose and will not yield; filing first does not delay it at all.
- Trap. A review process researchers route around by posting preprints.
[ ] Diary preprint postings, abstract publication, and thesis deposits separately from journal dates.
- Trap. Treating publication as the trigger when a preprint went up months earlier.
[ ] Confirm inventorship against conception rather than authorship.
- Authority. 35 U.S.C. § 115; 35 U.S.C. § 116.
[ ] Paper multi-institution collaborations before the work.
- Authority. 35 U.S.C. § 102(c) requires the agreement to be in effect on or before the effective filing date.

Acquired or in-licensed families

[ ] Read the provisionals, not the schedule.
- Why. The represented priority date and the supported priority date are frequently different.
[ ] Verify every cross-reference in the chain.
- Trap. A defective benefit claim inherited with the portfolio.
[ ] Confirm co-pendency status of every family before closing.
- Trap. Buying a portfolio with every family already closed.
[ ] Ask for the disclosure log, and treat its absence as a finding.
- Authority. See IP Due Diligence Toolkit.

Fast-moving product development

[ ] File a series of provisionals rather than one.
- Why. Each captures what exists at its date; a single early filing supports none of the year's subsequent work.
[ ] Convert all of them in one non-provisional at twelve months from the earliest.
[ ] Track which claims depend on which provisional.

Domestic-only strategies

[ ] Make it a decision, recorded, not an omission.
[ ] Consider the non-publication request deliberately.
- Authority. 35 U.S.C. § 122(b). It preserves secrecy until grant and permanently forfeits foreign rights if certified and foreign filing later occurs.
- Trap. Certifying non-publication and then filing abroad, which has consequences beyond losing the foreign right.

Phase 18. The disclosure log

Phase 1 is only reliable if the information is captured as it happens rather than reconstructed at intake, and the log is the artifact that makes that possible. It belongs to the business rather than to counsel.

[ ] One row per external event, across the whole company.
- Why. Patent deadlines are created by marketing, sales, and engineering activity, and no single function sees all of it.
- Trap. A log maintained by R&D alone, which misses every sales event.
[ ] Record the event type.
- Why. Publication, demonstration, offer, sale, deployment, or posting — the category determines which bar applies.
- Authority. 35 U.S.C. § 102(a)(1).
[ ] Record the date the material became publicly accessible, not the date it was created.
- Trap. The date on the document rather than the date it went out.
[ ] Record whether a confidentiality obligation applied, and attach it.
- Why. It is the difference between a public use and a private one, and it turns on the agreement's terms and whether it was honored.
- Trap. A verbal understanding, or an agreement signed after the disclosure.
[ ] Attach the artifact itself, archived.
- Why. Establishing what was disclosed matters as much as when.
[ ] Review the log monthly against pending and contemplated filings.
- Trap. A log that exists and is never read, which creates a record of knowledge without action.
[ ] Add one line to the product launch checklist: has a filing decision been made for anything disclosed at this event?
- Why. It reaches the people who create the deadlines, and it is the highest-return process change available.

Phase 19. Who owns which phase

The chain fails at the handoffs, so ownership should be explicit.

[ ] Phases 1 and 18 belong to the business.
- Why. The disclosure log and the launch-checklist question sit with product operations, because counsel is not in the room when a trade show is planned or an abstract submitted.
[ ] Phases 2 through 7 belong to patent counsel.
[ ] Phase 8 belongs jointly to counsel and the business.
- Why. Country selection is a commercial judgment informed by legal input, and counsel deciding it alone produces the map-covering pattern.
[ ] Phases 9 through 12 belong to counsel with foreign associates.
[ ] Phase 13 belongs to whoever owns the annuity budget.
- Why. That is the only person who can act on a recommendation to abandon.
[ ] Phase 14 belongs to a named individual, reviewed with the client annually.
- Trap. An annual review that is nobody's job and therefore does not happen, which is how portfolios drift out of alignment with the business.
[ ] One person is accountable for the family across all jurisdictions.
- Why. Without it, a family becomes a set of unrelated prosecutions that happen to share a specification, with inconsistent scope and inconsistent statements about the same art.

A closing note. Almost everything in this checklist is cheap, and almost everything it prevents is expensive or permanent. The disclosure screen costs nothing and determines whether foreign rights exist. The provisional drafting standard costs a small multiple of a bad provisional and preserves the invention rather than a document. The country-selection discipline at month twenty-four costs an hour and moves the largest number in the portfolio. And the two failures that cannot be repaired at any price — a closed family and a pre-filing foreign disclosure — are both prevented by a single line item in a docket and a single line item in a launch checklist.

Both lines take a minute to add and neither will ever appear as a billable achievement, which is precisely why they are the ones most often missing.

Key Authorities at a Glance

| Authority | Proposition | Phase | |---|---|---| | 35 U.S.C. § 100(i) | Effective filing date defined | 4 | | 35 U.S.C. § 102(a)(1) | Prior art before the effective filing date | 1 | | 35 U.S.C. § 102(b)(1) | The U.S. grace period, which does not travel | 1 | | 35 U.S.C. § 111(b) | Provisional applications | 3 | | 35 U.S.C. § 112(a) | Support; what the provisional preserves | 3, 5 | | 35 U.S.C. § 119(a) | Paris Convention priority | 5 | | 35 U.S.C. § 119(e) | Benefit of a provisional | 3, 5 | | 35 U.S.C. § 120 | Domestic continuity; co-pendency | 4, 14 | | 35 U.S.C. § 122(b) | Publication and non-publication requests | 5 | | 35 U.S.C. § 133 | Reply deadlines and abandonment | 14 | | 35 U.S.C. § 184 | Foreign filing license | 2 | | 35 U.S.C. § 185 | Consequences of unlicensed foreign filing | 2 | | 35 U.S.C. § 261 | Assignment | 10 | | 35 U.S.C. § 351 | PCT implementation | 6 | | 35 U.S.C. § 363 | International application as a U.S. filing | 6 | | 35 U.S.C. § 365 | Right of priority from an international application | 6 | | 35 U.S.C. § 371 | National stage entry | 10 | | 37 C.F.R. § 1.56 | Duty to disclose art cited abroad | 7, 11 | | 37 C.F.R. § 1.131 | Antedating a reference, pre-AIA only | 4 |

The five things people get wrong

One: they tell clients "you have a year" without saying where. The grace period is a United States rule. Most of the world applies absolute novelty, so a trade-show demonstration before filing forecloses those rights permanently. This omission costs more foreign patent rights than any other advice given in this field.

Two: they file thin provisionals. A provisional preserves what it describes. A converted pitch deck buys a date for a pitch deck, and the claims the business actually needs get the date twelve months later.

Three: they conflate the twelve-month and thirty-month deadlines. Both are called "the PCT deadline." The first determines whether there is a PCT application at all; the second determines whether there are rights in any particular country.

Four: they choose countries at month twelve. The PCT exists to defer that decision by eighteen months. Applicants who decide early pay for the option and do not use it, and they file in markets that turn out not to matter.

Five: they budget entry rather than lifetime. Annuities dominate the cost, they escalate, and they begin during prosecution in several jurisdictions. Portfolios budgeted only for entry get pruned by lapse rather than by choice, which loses the wrong ones. See Filing a Patent Internationally.