Patent Term Checklist: PTA Audit, PTE Eligibility, Double Patenting Screening, and Terminal Disclaimer Consequences

By Casey Scott McKay · 2026-03-27

This checklist treats patent term as a portfolio discipline with hard, unrecoverable deadlines rather than as a prosecution detail. It starts by building the family expiration map that most owners have never seen, then reconstructs adjustment from the file wrapper, applies the overlap rule correctly, audits applicant-delay deductions, and diaries the reconsideration window that closes weeks after issuance. It installs a sign-off gate on terminal disclaimers requiring the surrendered term to be computed first, and it preserves the Section 121 safe harbor by capturing restriction groups and checking consonance at every amendment. It screens for double patenting exposure after Cellect and Allergan, prepares the extension election before approval because sixty days is not enough, and closes with transaction planning, docketing configuration, and the annual refresh.

IP and Technology > Patent Counseling Transactions | Checklist | Published 27 March 2026 - Updated 12 May 2026 | Casey Scott McKay - marksy.us

Summary. This checklist treats patent term as a portfolio discipline with hard, unrecoverable deadlines rather than as a prosecution detail. It starts by building the family expiration map that most owners have never seen, then reconstructs adjustment from the file wrapper, applies the overlap rule correctly, audits applicant-delay deductions, and diaries the reconsideration window that closes weeks after issuance. It installs a sign-off gate on terminal disclaimers requiring the surrendered term to be computed first, and it preserves the Section 121 safe harbor by capturing restriction groups and checking consonance at every amendment. It screens for double patenting exposure after Cellect and Allergan, prepares the extension election before approval because sixty days is not enough, and closes with transaction planning, docketing configuration, and the annual refresh.

Keywords: family expiration map · base term measure · adjustment reconstruction · overlap rule · applicant delay audit · reconsideration deadline · terminal disclaimer gate · surrendered term arithmetic · common ownership constraint · divisional styling · restriction group capture · consonance check · safe harbor preservation · double patenting screen · Cellect exposure · extension eligibility · fourteen year cap · sixty day election · maintenance fee interaction · annual refresh

How to use this checklist

| Phase | What it covers | |---|---| | 1 | The family expiration map | | 2 | The base term measure | | 3 | Reconstructing A delay | | 4 | Reconstructing B and C delay | | 5 | The overlap rule | | 6 | Applicant delay audit | | 7 | The reconsideration decision | | 8 | The terminal disclaimer gate | | 9 | Surrendered term arithmetic | | 10 | Alternatives to disclaiming | | 11 | Divisional styling | | 12 | Consonance maintenance | | 13 | Double patenting screen | | 14 | Cellect and Allergan exposure | | 15 | Extension eligibility | | 16 | The extension election | | 17 | Continuation sequencing | | 18 | Maintenance fee interaction | | 19 | Transaction planning | | 20 | Docketing configuration | | 21 | Diligence | | 22 | Annual refresh |

Boxes marked [Gate] must clear before a disclaimer is filed, a divisional is styled, or an extension election is made.

The matter. A specialty pharmaceutical company mapped two families for the first time and found just under five patent-years surrendered by three terminal disclaimers, an adjustment figure five months understated with the reconsideration window long closed, and a pending continuation whose adjustment would be vulnerable after Cellect.

Phase 1. The family expiration map

[ ] [Gate] Build it before deciding anything else. One row per patent and pending application.
[ ] Record per row: relationship to the parent; earliest non-provisional filing date; provisional date if any; issue date; base twenty-year date; adjustment granted; adjustment recalculated; discrepancy; extension; every terminal disclaimer and its reference; term surrendered; effective expiration; claim type; next maintenance fee; common-ownership constraint; double patenting exposure.
[ ] Add a one-line claim type — composition, method of use, method of manufacture, apparatus.
- Why. Term without claim scope is a date without a meaning.
[ ] Sort by effective expiration, not by number. The sorted view is what makes the profile legible.
[ ] Highlight rows with adjustment above six months. Those are the patents worth defending, and they are frequently not the ones the business considers important.
[ ] Produce a second sheet listing every disclaimer pair, for corporate development.
[ ] Refresh annually and before any transaction, assertion, or licensing negotiation.

Phase 2. The base term measure

[ ] Twenty years from the earliest United States non-provisional filing to which the patent claims priority, under 35 U.S.C. § 154(a).
[ ] Confirm provisionals are excluded. A provisional under 35 U.S.C. § 111(b) gives priority without starting the clock — a full year of effective term.
[ ] Confirm continuations inherit the parent's date under 35 U.S.C. § 120.
- Trap. A continuation filed in year eight lives twelve years. Later filings add claim coverage within the family's life; they do not extend it.
[ ] Check continuation-in-part chains. New-matter claims are measured from the earliest application in the chain.
[ ] Confirm foreign priority under 35 U.S.C. § 119 does not start the clock.

Phase 3. Reconstructing A delay

[ ] Fourteen months from filing to the first office action on the merits.
[ ] Four months from a complete reply to the next office action.
[ ] Four months from a decision on appeal to further action.
[ ] Four months from issue fee payment to issuance.
[ ] Count each overrun in days. All the dates are in the file wrapper; this is mechanical.
[ ] Reference: 35 U.S.C. § 154(b) and 37 C.F.R. § 1.702.

Phase 4. Reconstructing B and C delay

[ ] B delay: pendency beyond three years from filing.
[ ] Exclude time consumed by continued examination, which is where most disputes live — Novartis v. Lee.
[ ] Exclude interference or derivation, appellate review, and applicant-requested delay.
[ ] C delay: interference, secrecy orders, and successful appellate review. Usually zero.
[ ] Record each exclusion with its date range, because the reconsideration request will need it.

Phase 5. The overlap rule

[ ] [Gate] Deduct only periods that actually overlap in calendar time.
- Why. Wyeth v. Kappos corrected the office's practice of treating A and B delay as categorically overlapping. This is the systematic error in older calculations and the most common source of understated adjustment.
[ ] Lay the periods on a calendar rather than working from totals.
[ ] Compute the union, not the sum.
[ ] Compare against the office's stated figure on the issue notification.

Phase 6. Applicant delay audit

[ ] Apply the three-month response benchmark, the largest single deduction under 37 C.F.R. § 1.704.
[ ] Check the other listed conduct — supplemental replies, papers after allowance, extensions of time.
[ ] [Gate] Test each deduction against whether the applicant could have acted earlier.
- Why. Supernus Pharmaceuticals v. Iancu holds delay cannot be assessed for a period in which no action was available.
[ ] Total the accumulated applicant delay across the portfolio as a separate figure.
- Why. A portfolio routinely taking full extensions is buying convenience with term, and the aggregate number makes that visible.

Phase 7. The reconsideration decision

[ ] [Gate] Diary the deadline at issuance. The window from issuance is measured in weeks; after that only a civil action, with its own deadline.
[ ] Set a materiality threshold once, as policy. Days are not worth pursuing; weeks or months on a commercially significant patent are.
[ ] Draft the request around the computation — a table of dates, delay categories, and the resulting figure.
[ ] Cite sparingly: Wyeth for overlap, Novartis v. Lee for continued examination, Supernus for unavailable action.
[ ] Keep it to a few pages, and diary the response.

Phase 8. The terminal disclaimer gate

[ ] [Gate] No terminal disclaimer is filed without recorded sign-off from the named holder of the family map.
[ ] [Gate] The sign-off request must include the months surrendered.
- Trap. A practitioner who cannot compute that number should not be filing the document.
[ ] Understand the common-ownership commitment. 37 C.F.R. § 1.321 makes the patent enforceable only while commonly owned with the reference patent — foreclosing separate assignment, spin-outs needing one patent, and exclusive licences structured as assignments.
[ ] Note irrevocability. Once recorded, generally not withdrawable under 35 U.S.C. § 253.
[ ] Record the decision and the arithmetic in the file, whichever way it goes.

Phase 9. Surrendered term arithmetic

[ ] Project the application's expiration including the adjustment it is likely to receive.
[ ] Identify the reference patent's expiration.
[ ] Subtract. That is the cost, in months.
[ ] Multiply by what the claims are worth in their final protected years, which is the only figure the business will engage with.
[ ] Present both numbers — months and value — in the sign-off request.

Phase 10. Alternatives to disclaiming

[ ] Argue patentable distinctness, where the claims genuinely are. Obviousness-type double patenting compares claims to claims, not claims to specification — a rejection relying on the reference disclosure is answerable on that ground.
[ ] Amend to distinguish, where narrowing costs less than the term.
[ ] Invoke the 35 U.S.C. § 121 safe harbor where a restriction supports it. Raise it explicitly; examiners do not apply it unprompted.
[ ] Abandon the application where the claims add little and the disclaimer would be costly. Occasionally correct.
[ ] File the disclaimer where the rejection is right, the term surrendered is small, and the family will never be split.
[ ] Consider the exposure position. Where the application will issue as a later-filed, later-issued member claiming a variant of an earlier-expiring relative, its adjustment is vulnerable anyway after In re Cellect — which is an argument for accepting the disclaimer.

Phase 11. Divisional styling

[ ] [Gate] Where a restriction requirement issues and the non-elected subject matter will be pursued, style the filing as a divisional.
- Why. G.D. Searle v. Lupin Pharmaceuticals holds the § 121 safe harbor does not extend to continuations, and a divisional-of-a-continuation chain can lose it.
[ ] Confirm there was an actual restriction requirement, not an election of species and not a voluntary decision to file separately.
[ ] Capture the restriction groups in the docket at the moment the requirement issues.
[ ] Link the divisional to those groups and flag it as safe-harbor eligible.
[ ] Do not default to "continuation" because it is the firm's usual label. The loss surfaces years later.

Phase 12. Consonance maintenance

[ ] [Gate] Check every amendment in a safe-harbor divisional against the recorded restriction groups.
- Why. Consonance is lost by ordinary claim drafting rather than by any deliberate act — Boehringer Ingelheim v. Barr Laboratories.
[ ] Confirm the claims stay on their side of the line of demarcation.
[ ] Flag any amendment that crosses back, and decide deliberately whether the claim scope is worth the safe harbor.
[ ] Re-check at allowance.

Phase 13. Double patenting screen

[ ] Run it off the map, not off a rejection.
[ ] Identify every commonly-owned pair claiming arguably obvious variants.
[ ] Compare expiration dates including adjustment.
[ ] Apply Gilead Sciences v. Natco Pharma: a later-issued but earlier-expiring patent can be a reference against an earlier-issued, later-expiring one. Expiration order controls, not issuance order.
[ ] Note AbbVie v. Mathilda & Terence Kennedy Institute for commonly owned patents with differing expiration dates.
[ ] Record the exposure on the map so it is visible at every subsequent decision.

Phase 14. Cellect and Allergan exposure

[ ] [Gate] Treat adjustment as contingent rather than vested.
- Why. In re Cellect assesses obviousness-type double patenting against the expiration date including adjustment, so the doctrine can take back what § 154(b) gave.
[ ] Confirm the parent is protected. Allergan USA v. MSN Laboratories holds a first-filed, first-issued claim cannot be invalidated by a later-filed, later-issued claim in the same family expiring earlier.
[ ] Locate the exposure in continuations with substantial adjustment claiming variants of earlier-expiring relatives.
[ ] Note the extension asymmetry. Novartis AG v. Ezra Ventures holds a § 156 extension is not cut back by the doctrine. Extension is more durable than adjustment.
[ ] Sequence filings accordingly. Obtain core claims first and earliest.

Phase 15. Extension eligibility

[ ] Confirm the patent claims the product, a method of using it, or a method of manufacturing it.
[ ] Confirm there was a regulatory review period before commercial marketing.
[ ] Confirm this approval is the first permitted commercial marketing of the product.
[ ] Confirm the patent has not previously been extended.
[ ] Reference: 35 U.S.C. § 156.

Phase 16. The extension election

[ ] [Gate] Prepare the comparison before approval is expected. Sixty days is not enough to start from scratch, and the decision cannot be revisited.
[ ] Compute per candidate: half the testing phase plus all of the approval phase; less any due diligence reduction; capped at five years; with total remaining term capped at fourteen years from approval.
[ ] Identify which cap binds. For patents issued late in development the fourteen-year cap usually controls and compresses the differences between candidates.
[ ] Default to the composition claim, hardest to design around — but do the arithmetic, since a longer-lived composition patent may make extending the method patent produce more total exclusivity.
[ ] Tell the regulatory team their diligence affects term.
[ ] Note extension survives a terminal disclaimer — Merck v. Hi-Tech Pharmacal.
[ ] [Gate] Diary the sixty-day deadline the day approval is received.

Phase 17. Continuation sequencing

[ ] Obtain core claims first and earliest, since first-filed first-issued claims are the protected position.
[ ] Use provisionals deliberately under 35 U.S.C. § 111(b).
[ ] Treat continuation-in-part practice as a term decision, not only a disclosure decision.
[ ] Respond within three months wherever possible.
[ ] Avoid unnecessary continued examination, which suspends B-delay accrual.
[ ] Record the term consequence of each of these choices at the time it is made.

Phase 18. Maintenance fee interaction

[ ] Put the map in front of whoever makes fee decisions under 35 U.S.C. § 41.
- Why. A patent with four years remaining is a different proposition from a sibling with seven, and pruning on claim scope alone prunes the wrong patents.
[ ] Check fee status across the family, since an unpaid fee ends the patent regardless of adjustment or extension.
[ ] Flag patents whose remaining term no longer justifies the fee.
[ ] Flag patents whose adjustment makes them the family's longest-lived, which are usually worth paying for regardless of claim scope.

Phase 19. Transaction planning

[ ] [Gate] Produce the disclaimer pair list before any perimeter is drawn.
[ ] Model expiration into valuation, since a patent schedule listing numbers and titles says nothing about protection period.
[ ] Check adjustment figures a seller has relied on.
[ ] Screen the target for Cellect exposure.
[ ] Confirm the extension election and whether it was optimal, because it cannot be changed.
[ ] Check maintenance fee status. See the IP Due Diligence Toolkit for Mergers, Financings, and Asset Sales.

Phase 20. Docketing configuration

[ ] [Gate] An adjustment check task on every issue notification, with the reconsideration deadline computed and diaried simultaneously.
[ ] [Gate] A terminal disclaimer approval gate that will not permit filing without a recorded approval including the months surrendered.
[ ] Restriction group capture when a requirement issues, linked to any divisional filed.
[ ] A three-month response benchmark alert.
[ ] A continued examination flag noting suspended B-delay accrual.
[ ] An extension watch on families covering products in regulatory review.
[ ] A monthly exception report: patents issued without an adjustment check, and disclaimers filed without approval.

Phase 21. Diligence

[ ] Ask for the map, and build a rough one from patent face data if none exists.
[ ] Recalculate adjustment on the three most valuable patents.
[ ] Ask for every terminal disclaimer and its reference patent.
- Trap. Sellers omit disclaimers from schedules because nobody thinks of one as an encumbrance.
[ ] Check safe-harbor divisionals for consonance.
[ ] Screen for Cellect exposure.
[ ] Confirm the extension election.
[ ] Check maintenance fee status.
[ ] Price rather than warrant. Term shortfalls are quantifiable and permanent, and a representation that patents are in force says nothing about when they expire or whether they can be separated.

Phase 22. Annual refresh

[ ] Rebuild the map with new issuances, disclaimers, adjustment figures, and fee status.
[ ] Re-run the double patenting screen, since new issuances create new pairs.
[ ] Check consonance in every safe-harbor divisional.
[ ] Confirm every disclaimer filed in the year had recorded approval with arithmetic attached.
[ ] Total applicant delay accumulated across the portfolio.
[ ] Re-send the disclaimer pair list to corporate development.
[ ] Refresh the extension memo for products approaching approval.
[ ] Report four numbers: total adjustment granted; total term surrendered by disclaimers in the year; adjustment discrepancies found and pursued; and the family's true end date for each significant product.

Outcome. The map, built for the first time, showed three terminal disclaimers on Family A continuations that had surrendered adjustment of fourteen, twenty-two, and twenty-nine months — just under five patent-years in total, of which two of the three underlying rejections had been arguable on distinctness grounds. The disclaimers also tied four patents to permanent common ownership, which mattered because an exclusive licence of the formulation technology structured as an assignment was under discussion. The composition patent's adjustment had been calculated under the office's older overlap methodology and was five months understated, but the reconsideration window had closed years earlier and the term was unrecoverable. The extension election had been taken on the composition patent, which was correct, though the decision had been made in a hurry. A pending Family B continuation would, if granted claiming an obvious variant of the earlier-expiring formulation patent, have vulnerable adjustment after Cellect with no Allergan protection — so the decision was taken to argue distinctness rather than disclaim, accepting one further office action cycle. Going forward: sign-off on every disclaimer, an adjustment check docketed on every issuance, restriction groups captured, and the map refreshed annually.

Phase 23. The map, as a template

Use this column set for Phase 1. Each column earns its place.

| Column | Why it is there | |---|---| | Patent or application number | The identifier everything keys to | | Relationship | Parent, continuation, divisional, or continuation-in-part — and whether a divisional followed a restriction, which decides safe harbor availability | | Earliest non-provisional filing | The base measure under 35 U.S.C. § 154(a) | | Provisional date, if any | Records the year of term preserved; flags families where provisionals were not used | | Issue date | Needed for adjustment reconstruction and extension caps | | Base twenty-year date | Filing plus twenty | | Adjustment granted | The office's figure | | Adjustment recalculated | Yours, from Phases 3 to 6 | | Discrepancy | The number that triggers Phase 7 | | Extension | Zero for all but one patent per approved product | | Terminal disclaimer, and to what | The two most consequential facts on the row | | Term surrendered | Computed, in months — frequently for the first time | | Effective expiration | The date the business should plan around | | Claim type | Composition, method of use, method of manufacture, apparatus | | Next maintenance fee | An unpaid fee under 35 U.S.C. § 41 ends everything | | Common-ownership constraint | Which patent this one cannot be separated from | | Double patenting exposure | Which commonly-owned relative claims a variant and expires earlier |

[ ] Sort by effective expiration. The sorted view is what makes the flattening caused by disclaimers visible immediately.
[ ] Highlight adjustment above six months.
[ ] Produce the disclaimer pair sheet separately, for corporate development.

Phase 24. Reconsideration request outline

[ ] 1. Confirm the deadline is open. Weeks from issuance for reconsideration; a separate window for a civil action; nothing afterwards.
[ ] 2. Identify the specific computational error the office can verify from its own record — an overlap deduction applied to non-overlapping periods, a B-delay exclusion applied to time not consumed by continued examination, or an applicant-delay deduction for a period in which no action was available.
[ ] 3. Show the arithmetic as a table of dates, delay categories, and the resulting figure. The office is checking its calculation against yours; a request that argues without computing is not useful.
[ ] 4. Cite three authorities, not thirty — Wyeth v. Kappos, Novartis v. Lee, Supernus Pharmaceuticals v. Iancu.
[ ] 5. Keep it to a few pages.
[ ] 6. Diary the response and be ready to escalate within the civil action window if the point is worth pursuing.

Phase 25. Evidence and data request

Assemble once per family; reuse for diligence, licensing, and litigation.

[ ] Complete file wrappers for every family member, with all dates.
[ ] Issue notifications showing the office's adjustment calculation.
[ ] Every terminal disclaimer filed, with its reference patent and the approval record if one exists.
[ ] Restriction requirements and the groups they defined.
[ ] Every divisional's claims as filed and as amended, for the consonance check.
[ ] Maintenance fee payment records across the family.
[ ] Any extension application and its grant, with the regulatory review period calculation.
[ ] Regulatory approval dates and correspondence bearing on due diligence during review.
[ ] Assignment and recordation records, which interact with the common-ownership constraint.
[ ] Prior reconsideration requests or civil actions concerning adjustment.
[ ] Licence agreements referencing expiration dates, which may reference a date a disclaimer has since changed.

Why this belongs here. Several items exist only in the file wrapper and are never extracted, and the disclaimer approval records usually do not exist at all — which is itself the finding that justifies installing the Phase 8 gate.

Phase 26. Portfolio-type boxes

Run the base checklist, then the boxes for the portfolio in play.

Life sciences with an approved product.

[ ] Build the map per product, not per family — the commercial question is how long the product is protected.
[ ] Prepare the extension memo before approval; the sixty-day window under 35 U.S.C. § 156 does not accommodate starting late.
[ ] Screen dense continuation families for In re Cellect exposure, which concentrates here.
[ ] Coordinate with regulatory affairs on due diligence during the review period, which reduces the extension.
[ ] Reconcile the map against any abbreviated-approval litigation timetable.

Software and electronics.

[ ] The largest aggregate term loss and the least noticed, because no single disclaimer looks significant and there are dozens.
[ ] The Phase 8 sign-off gate matters more here than anywhere.
[ ] Extension is irrelevant, which sometimes leads to the whole subject being ignored.
[ ] Long continuation chains make Phase 13 screening a recurring rather than occasional task.

Medical devices.

[ ] Extension eligibility varies by product classification; do the analysis early rather than assuming either way.
[ ] Utility and design families may cover the same product with different term profiles; map both.

Acquired portfolios.

[ ] Adjustment was computed by someone else and reconsideration windows are closed.
[ ] Disclaimers were filed by counsel no longer available to explain them.
[ ] Build the map during diligence, price what it shows, and accept that nothing lost is recoverable.

University and institutional portfolios.

[ ] Long pendency produces substantial adjustment, which makes Phase 5 and Phase 7 unusually valuable.
[ ] Licence royalty terms referencing expiration may reference a date a disclaimer has since aligned downward — check every agreement against the map.
[ ] Federal funding obligations sit alongside term and should be recorded on the same sheet.

Companies with no regulated products.

[ ] Skip Phases 15 and 16 entirely.
[ ] Everything else applies unchanged, and the absence of the extension question is not a reason to skip the map.

Phase 27. The ninety-day installation

[ ] Days 1-15. Build the map for the two or three most commercially significant families.
[ ] Days 5-20. Install the terminal disclaimer sign-off gate and the issuance adjustment check. These are the forward-looking controls and should run before the audit finishes.
[ ] Days 15-40. Recalculate adjustment on every patent still within its reconsideration window; file where the discrepancy is material.
[ ] Days 30-50. Capture restriction groups for pending divisionals; check consonance on each.
[ ] Days 40-60. Run the double patenting screen across the mapped families; record exposure.
[ ] Days 50-70. Prepare the extension memo for any product approaching approval.
[ ] Days 60-80. Produce the disclaimer pair list and deliver it to corporate development. Put the map in front of whoever makes maintenance fee decisions.
[ ] Days 80-90. Configure the docket per Phase 20. Name the map holder. Calendar the annual refresh. Report the baseline four numbers.

What is deliberately deferred. Recalculating adjustment on patents whose reconsideration windows have closed. The exercise has diagnostic value — it reveals whether the office's methodology was applied correctly and therefore whether newer patents are likely understated — but the term is unrecoverable, and effort belongs where something can still be done.

Phase 28. Answering a double patenting rejection

The decision tree, run with the arithmetic in front of you rather than from instinct.

[ ] [Gate] First, compute the cost of disclaiming. Projected expiration of the application including likely adjustment, minus the reference patent's expiration. Two months and two years are entirely different problems.
[ ] Test the rejection's basis. The doctrine compares claims to claims, not claims to specification. A rejection relying on the reference patent's disclosure is answerable on that ground alone.
[ ] Test distinctness on the merits. Where the later claims recite a limitation absent from the reference claims and not suggested by them, the rejection is arguable.
[ ] Check the safe harbor. Was there a restriction requirement, is this a divisional filed as a consequence, and has consonance been maintained? All three true means 35 U.S.C. § 121 removes the pair entirely — and examiners do not apply it unprompted.
[ ] Consider amending to a limitation the reference claims do not reach, where narrowing costs less than the term.
[ ] Consider the exposure position. Where the application will issue as a later-filed, later-issued member claiming a variant of an earlier-expiring relative, its adjustment is vulnerable under In re Cellect with no protection from Allergan USA v. MSN Laboratories — which is an argument for accepting the disclaimer, since the adjustment may not survive regardless.
[ ] [Gate] Record the analysis in the file whichever way it goes, with the arithmetic. The next practitioner on the matter and any later diligence exercise both need it.

Phase 29. Quarterly metrics

Six numbers, reported with the portfolio.

[ ] Patents issued in the quarter with an adjustment check completed, as a proportion. Target: all of them, because the window closes in weeks.
[ ] Adjustment discrepancies found, and total months at stake.
[ ] Terminal disclaimers filed, and total months surrendered. The second figure is the one nobody has ever seen, and it changes behaviour the first time it appears.
[ ] Disclaimers filed without a recorded approval. Target: zero. Any non-zero value means the Phase 8 gate is not working.
[ ] Divisionals filed following a restriction, and how many were styled as divisionals. The gap is forfeited safe harbor.
[ ] Applicant delay accumulated in the quarter, in days, across the portfolio. A portfolio routinely taking full extensions of time is buying convenience with term, and this number makes the trade visible.

And one annual figure: the family's true end date for each significant product, alongside the date the business currently plans around. Where those differ, that difference is the whole reason this checklist exists.

Phase 30. Four sentences worth saying

[ ] To prosecution counsel. "No terminal disclaimer without sign-off, and the request has to include the months surrendered. If you cannot compute that number, you cannot file the document." This closes the largest source of quiet term loss in an ordinary portfolio and costs about ten minutes per matter.
[ ] To the docketing team. "Every issue notification generates two tasks: check the adjustment, and diary the reconsideration deadline." The window closes in weeks, nothing recovers the term afterwards, and this is the highest-value configuration change available.
[ ] To the client, at the first portfolio review. "Claim scope can be fixed by a continuation. Term cannot be fixed by anything. A missed reconsideration window, a disclaimer nobody computed, a divisional styled as a continuation — all permanent, and all of them happened without anyone deciding they should."
[ ] To corporate development, unprompted. "Here is the list of patents that cannot be separated from each other. It exists because of documents filed to clear routine rejections, and it constrains how this portfolio can be divided. You should have it before you draw a perimeter, not during the diligence call where a buyer's counsel finds it."

Why these four. Every mechanism in this checklist is computable from documents already in the file, and almost none of it is ever computed — not because it is difficult, but because it sits between prosecution, portfolio management, corporate development, and regulatory affairs, and each function assumes another is watching. Naming one person to hold the map, approve disclaimers, and run the annual refresh solves more of this than any amount of doctrinal sophistication.

Phase 31. Where term is lost, ranked

Run this list against any portfolio being examined for the first time. It is ordered by how often each appears, not by how much each costs.

[ ] Terminal disclaimers filed without computing the cost. Most common, most avoidable, and entirely preventable by a sign-off gate.
[ ] Adjustment miscalculated and never checked, with the reconsideration window closing silently a few weeks after issuance.
[ ] Divisionals styled as continuations, forfeiting the 35 U.S.C. § 121 safe harbor and surfacing years later as a rejection against a patent that should have been protected.
[ ] Consonance lost by ordinary amendment in a divisional that was properly styled at filing.
[ ] Provisionals not used, giving away a year of effective term at the end of the patent's most valuable period to save a modest filing cost at the beginning.
[ ] Continuation-in-part claims pulled back to an early priority date where the priority was not actually needed.
[ ] Applicant delay accumulated casually through routine extensions of time, each a day-for-day deduction under 37 C.F.R. § 1.704.
[ ] Unnecessary continued examination, which suspends B-delay accrual.
[ ] The extension elected on the wrong patent, or missed entirely at the sixty-day deadline under 35 U.S.C. § 156.
[ ] Maintenance fees missed, which ends the patent regardless of everything else.
[ ] And the one nobody counts: a family whose expiration profile has never been mapped, so the business plans around a date that is wrong in one direction or the other — and nobody discovers it until a licensing negotiation, a launch decision, or a diligence call.

Key Authorities at a Glance

| Authority | Proposition | |---|---| | 35 U.S.C. § 154(a) | Twenty years from earliest non-provisional filing | | 35 U.S.C. § 154(b) | Adjustment; A, B, and C delay | | 35 U.S.C. § 156 | Extension for regulatory review | | 35 U.S.C. § 253 | Terminal disclaimer | | 35 U.S.C. § 121 | Restriction; safe harbor | | 35 U.S.C. § 111 | Provisionals do not start the clock | | 35 U.S.C. § 119 | Foreign priority does not start the clock | | 35 U.S.C. § 120 | Continuations inherit the parent's date | | 35 U.S.C. § 41 | Maintenance fees | | 37 C.F.R. § 1.321 | Disclaimer requirements | | 37 C.F.R. § 1.702 | Office delay categories | | 37 C.F.R. § 1.704 | Applicant delay reductions | | Wyeth v. Kappos | The overlap rule | | Novartis v. Lee | Continued examination and B delay | | Supernus Pharmaceuticals v. Iancu | No delay where no action was possible | | Gilead Sciences v. Natco Pharma | Expiration order controls | | In re Cellect | Doctrine assessed against adjusted expiration | | Allergan USA v. MSN Laboratories | First-filed, first-issued claim protected | | AbbVie v. Mathilda & Terence Kennedy Institute | Differing expiration dates | | Merck v. Hi-Tech Pharmacal | Extension survives a disclaimer | | Novartis AG v. Ezra Ventures | Extension not cut back by the doctrine | | Novartis Pharmaceuticals v. Breckenridge | Pre-URAA references | | G.D. Searle v. Lupin Pharmaceuticals | Safe harbor limited to divisionals | | Boehringer Ingelheim v. Barr Laboratories | Consonance | | Eli Lilly v. Barr Laboratories | Double patenting analysis | | In re Longi | Foundational statement |

The five things people get wrong

Filing a terminal disclaimer without computing what it costs. The document is one page and the consequences are permanent: the adjusted tail above the reference patent's expiration is surrendered, and the two patents are tied to common ownership forever under 37 C.F.R. § 1.321. A practitioner who cannot state the months being given up should not be filing it.

Never checking the adjustment calculation. The office's figure is on the patent, it is frequently wrong, and the reconsideration window closes weeks after issuance. A portfolio of a hundred patents with an average error of three months is twenty-five patent-years nobody claimed.

Styling a divisional as a continuation. Where a restriction requirement issues, filing a divisional consonant with the groups invokes the 35 U.S.C. § 121 safe harbor and removes the pair from double patenting analysis entirely. Defaulting to "continuation" because it is the firm's usual label forfeits that, and the loss surfaces years later in a rejection.

Believing a continuation extends the family. It expires twenty years from the parent's filing date under 35 U.S.C. § 154(a). Continuations add claim coverage within the family's life; they never extend it.

Treating adjustment as vested. After In re Cellect, obviousness-type double patenting is assessed against the adjusted expiration date, so the doctrine can take back what the statute granted — and only the first-filed, first-issued claims are protected by Allergan USA v. MSN Laboratories.