A PCT application that proceeds smoothly in the United States, Europe or Japan can still run into procedural trouble in India. These PCT mistakes in India cluster at four points: Section 39 clearance before filing, the 31-month entry deadline and, for newer applications, the 31-month examination deadline, the Form 3 duty, and the First Examination Report period.
This guide reflects the Indian Patents Act and Patents Rules as amended to October 2026, and the PCT Regulations in force from 1 January 2026. It is written for foreign counsel and in-house teams managing PCT families that designate India.
Quick answer: Four of the ten mistakes are hard to repair after the event: a PCT filing by an Indian resident without Section 39 clearance, missing the 31-month national phase deadline or the national fee and any required English translation due by it, a request for examination not filed in time, and an unanswered First Examination Report once the extended period has run. The other six raise cost and validity risk and are avoided by getting each decision right at the stage it arises.
PCT mistakes and their deadlines at a glance
Most of the ten turn on a time limit. The table sets out each period and the event that starts it; the sections that follow explain what each one means in practice.
| Step | Period | Counted from |
| Correct or add a PCT priority claim | 16 months (from the changed priority date, if that ends first), or until 4 months after the international filing date if later | Priority date |
| Ask the receiving Office to restore priority (not given effect in India) | 2 months | End of the 12-month priority period |
| Amend claims under Article 19 | 2 months or 16 months, whichever ends later | Search report transmittal; priority date |
| File a Chapter II demand | 3 months or 22 months, whichever ends later | Search report and written opinion transmittal; priority date |
| Enter the Indian national phase | 31 months | Earliest priority date claimed, or international filing date if none |
| File the priority document in India, unless supplied in the international phase, the priority application was filed in India, or the document is available to India from a digital library | Before 31 months, then 3 months on invitation | Priority date; invitation |
| Request examination (applications filed on or after 15 March 2024) | 31 months | Priority date or filing date, whichever is earlier |
| File Form 3 | 6 months | Actual date of filing in India |
| Update Form 3 | 3 months | Issue of the First Examination Report |
| Answer the First Examination Report | 6 months, plus 3 months on a Form 4 request (file it within the 6 months as a docketing precaution) | Issue of the First Examination Report |
Before filing the PCT application
Two decisions are fixed before filing: whether an Indian resident needs Section 39 clearance, and which International Searching Authority to choose. Both shape national phase entry in India and are hard to change later.
Mistake 1: Section 39 not cleared before filing
A person resident in India may not file, or cause to be filed, a patent application outside India without a written permit from the Controller, unless an Indian application for the same invention was filed at least six weeks earlier and no secrecy direction is in force. The restriction does not apply where the invention was first filed outside India by a person resident outside India. The Act does not define “resident”, so the safer course is to check every inventor and applicant with an Indian connection before the filing date.
Filing the PCT application at the Indian Patent Office as receiving Office does not avoid Section 39. In Puneet Kaushik v Union of India, a Division Bench of the Delhi High Court held that a PCT application filed at the Indian Patent Office has the legal consequences of an application filed outside India, and that the international filing date could be accorded only once the permit was granted, not when the papers were handed in.
There are two compliant routes: file in India and wait six weeks with no secrecy direction in force, or obtain a permit on Form 25. The official fee for Form 25 on e-filing is ₹1,600 for a natural person, startup, small entity or educational institution and ₹8,000 for others. The Controller decides the request within 21 days of its filing; for inventions relevant to defence or atomic energy, the 21 days run from receipt of the Central Government’s consent. Our foreign filing licence guide explains the Form 25 route.
The consequences of filing without clearance are serious. The Indian application is deemed abandoned, any patent granted is liable to be revoked, and the contravention is itself a ground of revocation. It is also an offence punishable with imprisonment of up to two years, a fine, or both. Since 1 June 2026, the criminal penalty does not apply where the Central Government is of the opinion that the invention was not relevant for defence purpose or atomic energy at the time of the contravention; abandonment and revocation are unaffected.
Mistake 2: ISA chosen without Indian prosecution in view
Naming the Indian Patent Office as International Searching Authority, or electing it as International Preliminary Examining Authority, is one ground for expedited examination in India on Form 18A. An applicant who names another searching authority can keep this ground by electing India as examining authority in a Chapter II demand filed in time, where India is competent for the receiving Office used; otherwise it must rely on another ground. India is available as searching authority only for filings at the receiving Offices of India, Japan (English filings only) or Iran, or at the International Bureau by an applicant entitled to one of them; the same offices open India as examining authority, without the English condition, whichever authority searched. Designating India does not make it available as either authority.
Other grounds for expedited examination do not depend on the authority chosen: the applicant is a startup or a small entity; the applicant is a natural person, or all joint applicants are natural persons, and at least one is female; the applicant is a government department, a government-owned or controlled statutory institution, a government company, or an institution wholly or substantially financed by the government; the application is in a sector notified by the Central Government; or the applicant is eligible under an arrangement between the Indian Patent Office and a foreign patent office. A university or institution set up by a Central, Provincial or State Act qualifies on this ground only if the Government owns or controls it; a private university does not, even though it pays the lower fee. Form 18A can be filed only electronically, within the ordinary period for requesting examination.
The Form 18A fee on e-filing is ₹60,000 for other applicants, against ₹8,000 for a natural person, startup, small entity or educational institution. The lower fee is not itself a ground: an educational institution, for example, still needs one of the grounds above. The search fee comparison and the full decision on authorities are in our guides to choosing an International Searching Authority from India and designating India as ISA.
During the international phase
The international phase is where a priority or claims defect can be dealt with once for the whole family, but only within fixed periods under the PCT. Once those periods pass, the same defect can resurface in each designated office, including India.
Mistake 3: priority claim errors left uncorrected
A priority claim can be corrected or added within 16 months from the priority date (or from a changed priority date, whichever 16-month period ends first), and in any case until four months from the international filing date. If the correction moves the priority date, deadlines not yet expired, including the 31 months for India, run from the new date. A defective claim not corrected in time (or within one more month, if the correction arrives before the Office declares it void) is treated as void for the PCT procedure, though not merely because the earlier application number is missing, a detail does not match the priority document, or the international application was filed within two months after the priority year ended. After that window, an obvious mistake can still be rectified on a request made within 26 months from the priority date, but not if the rectification would change the priority date.
Where the international application is filed after the 12-month priority year but within two months of its end, a receiving Office can restore the right of priority on a request made within those two months, applying a “due care” or an “unintentional” test; each receiving Office applies at least one test and may apply both. India has told WIPO that restoration of priority is incompatible with its law, both when it acts as receiving Office and when it acts as designated Office, according to WIPO’s incompatibilities table (status 3 September 2026).
The practical consequence for a family that will enter India is that a priority restored by another receiving Office should not be relied on to carry into the Indian application. Our guide to the missed 12-month PCT deadline covers the restoration options.
Mistake 4: written opinion not reviewed before the international deadlines
An objection in the written opinion that is not dealt with during the international phase can resurface in each designated office, including India. Amending under Article 19 or demanding Chapter II examination is optional, and answering the objections in Indian prosecution instead is a legitimate choice; the mistake is letting the periods pass without reviewing the opinion. Both periods normally close before national phase entry, unless the applicant asks an office to start national processing early.
Article 19 amendments to the claims must reach the International Bureau within two months from transmittal of the search report or 16 months from the priority date, whichever is later; a late amendment still counts if it arrives before the technical preparations for international publication are complete. A Chapter II demand, which allows amendments to the claims, description and drawings, must be filed within three months from transmittal of the search report and written opinion or 22 months from the priority date, whichever is later.
Both routes carry into India: the Indian application includes Article 19 amendments communicated to India and amendments made in Chapter II. The tools are compared in our guides to Article 19 and Article 34 amendments and Chapter II demand strategy.
At national phase entry in India
The essential entry requirements are Form 1, the national fee and, where needed, a verified English translation, all before 31 months. The examination request and Form 3 have their own deadlines, each needing its own docket entry; the priority document, where required, is due by the same 31-month limit, with a further three months only after an invitation. A missed entry or examination deadline means the application is deemed or treated as withdrawn.
Mistake 5: entry papers and translation not prepared in time
Before 31 months, the applicant must file the national phase application, made on Form 1, pay the national fee and, where the international application was not filed or not published in English, file an English translation verified by the applicant or an authorised person as correct and complete. An international application that does not meet these requirements is deemed withdrawn in India.
The translation covers the description, the claims as filed, any text in the drawings and the abstract, plus the Article 19 amended claims and statement where India is not elected, or the annexes to the international preliminary examination report where it is. If a translation of the amended claims or annexes is not filed even after an invitation, those amendments are disregarded. Translation time should therefore be built into the docket well before month 31.
The priority document is normally submitted to the International Bureau or receiving Office within 16 months from the priority date (a copy reaching the International Bureau later but before international publication counts as on time), or, where the receiving Office issued it, the applicant asks that Office within the same 16 months to send it to the International Bureau, or asks the International Bureau before publication to obtain it from a digital library. If none of these was done, it must be filed in India before 31 months, and if it is still missing three months after the Patent Office’s invitation, the priority claim is disregarded. This filing duty does not apply where the priority application was filed with the Indian Patent Office, or where the document is available to the Indian Patent Office from a digital library.
A verified English translation of the priority document is needed by the same deadline only in two cases: where the validity of the priority claim matters to patentability, or where the international filing date depends on incorporating an element or part of the priority document by reference. It is not required for every non-English priority document, and the digital-library exception does not excuse it. The Controller’s general power to correct procedural irregularities does not reach the 31-month limit, the disregard of untranslated amendments or the priority-document rule. The entry checklist is in our guide to PCT national phase entry in India.
Mistake 6: treating the 31-month deadline as flexible
The time limit for national phase entry in India is 31 months from the priority date, meaning the earliest priority date claimed, or the international filing date where no priority is claimed. The Controller’s general power to correct procedural irregularities expressly excludes this deadline. A separate general power, Rule 138, allows the Controller to extend time or condone delay by up to six months on a Form 4 request made within those six months, and it lists no exclusions.
India has also told WIPO that the PCT’s reinstatement procedure is incompatible with its law. That procedure requires designated offices to restore rights where a timely request shows the delay in national phase entry was unintentional or, at the office’s option, occurred despite due care. So the PCT’s own reinstatement route is not available in India.
Our analysis of late PCT national phase entry in India covers how the Indian courts have treated late entry. The safe docketing rule is to treat 31 months as absolute and fix an internal deadline weeks earlier.
Mistake 7: the 2024 request-for-examination change not applied
The Patents (Amendment) Rules 2024, in force from 15 March 2024, cut the period for requesting examination from 48 months to 31 months. A request for examination on Form 18 must now be made within 31 months from the priority date or the filing date, whichever is earlier.
Applications filed before 15 March 2024 keep the earlier 48-month period. For a PCT national phase application, the relevant filing date is the international filing date. If no request for examination is made in time, the application is treated as withdrawn. Separately, the Patent Office does not begin processing a national phase application before 31 months, unless the applicant files the request for examination on Form 18 as an express request, at a higher fee; the Office may then process or examine the application earlier.
Two worked examples show the difference. For a PCT application with a priority date of 1 June 2023 and an international filing date of 31 May 2024, the national phase deadline and the examination deadline both fall 31 months after 1 June 2023, on 1 January 2026, so Form 1 and Form 18 should be filed together. For a PCT application with a priority date of 1 March 2023 and an international filing date of 1 March 2024, the national phase deadline is still 31 months (1 October 2025), but the examination request remains governed by the earlier 48-month period, counted from the priority date as the earlier date, so it falls on 1 March 2027 and the docket must carry a separate date.
The Controller’s general correction power expressly excludes the examination deadline. Rule 138 lists no exclusions, but an extension of this period should not be relied on. The three-month extension on Form 4 for answering the First Examination Report (Mistake 10) does not extend this period. Our PCT national phase entry guide covers the examination request in detail.
Mistake 8: wrong applicant category at entry
Indian official fees are set in two columns: one for a natural person, startup, small entity or educational institution, and a higher one for every other applicant, alone or jointly with those categories. The lower column applies only where the applicant qualifies, and the category claimed at entry has to be supported.
| Form and step (e-filing) | Natural person, startup, small entity or educational institution (₹) | Others (₹) |
| Form 1, national phase application (base fee) | 1,600 | 8,000 |
| Form 3, statement and undertaking | No fee | No fee |
| Form 18, request for examination | 4,000 | 20,000 |
| Form 18, express request for early processing | 5,600 | 28,000 |
| Form 18A, expedited examination | 8,000 | 60,000 |
| Form 4, extension of the examination report period, per month | 1,000 | 4,000 |
Source: First Schedule to the Patents Rules, verified as of October 2026. Physical filing carries an additional fee of 10 per cent, with the exact amounts set in the Schedule, and Form 18A cannot be filed physically.
A small entity, startup or educational institution claims its status on Form 28, with evidence: MSME registration for an Indian small entity, a document showing eligibility for an Indian startup or educational institution, and any other supporting document for a foreign applicant. Form 28 must accompany every fee-bearing document, and if the application is transferred, fully or partly, to anyone other than a natural person, startup, small entity or educational institution, the new applicant pays the fee difference with the transfer request. The full fee picture, including excess claim and page fees, is in our guide to PCT fees in India.
Mistake 9: Form 3 and Section 8 not kept current
Section 8 requires an applicant who is prosecuting an application outside India for the same or substantially the same invention, or who knows that a predecessor or successor in title is prosecuting one, to file a statement of those applications and an undertaking to keep the Controller informed of later ones up to grant. The Controller may also require details of how the application is being processed abroad at any time until grant or refusal, and the applicant must then supply them.
The statement and undertaking are filed on Form 3. For a PCT national phase application, Form 3 is due within six months from the actual date of filing in India. An update is due within three months from the issue of the First Examination Report, but the undertaking continues until grant and no rule fixes a time for filings made after that update, so as a precaution they should be reviewed and reported before grant. A fresh Form 3 directed by the Controller is due within two months of the direction, and the Controller may condone delay or extend the time for filing Form 3 by up to three months on a Form 4 request, at ₹2,000 per month for a natural person, startup, small entity or educational institution and ₹10,000 for others on e-filing.
Failing to disclose the required information, or giving information the applicant knew to be false in a material particular, is a ground of pre-grant opposition, of post-grant opposition within one year from publication of the grant, and of revocation. In Chemtura Corporation v Union of India, the Delhi High Court found at the interim stage that the patentee’s non-compliance with its Section 8 duties prima facie exposed the patent to revocation on this ground. Relying also on the government’s supply arrangements and the balance of convenience, the court did not continue the interim injunction and instead required three of the defendants to keep and file accounts; it stressed that its view was prima facie only. The national phase detail is in our guide to Section 8 and Form 3 for PCT applications.
After entry: the examination report
The final risk comes after a successful entry. The First Examination Report starts a fixed period to put the application in order for grant, and an application not in order within that period, as extended, is deemed abandoned. The period is counted from the date the report is issued, not the date it is received.
Mistake 10: examination report answered late
The applicant has six months from the date the First Examination Report is issued to put the application in order for grant. This can be extended by three months on a Form 4 request with the fee, made “before expiry of the period specified herein”. Before the 2024 amendments, the rule tied the request expressly to the six-month period; the new words may still be read as the six months, and the rule does not settle whether a later request will be accepted. An application not put in order within the period is deemed abandoned.
The same six months and three-month extension apply where expedited examination was requested. The Controller’s general correction power does not reach either period.
Where the report passes from the Indian agent to foreign counsel and then to the client, a deadline counted from the date of receipt rather than the date of issue can lose weeks; docketing from the issue date and, as a precaution, filing any Form 4 within the six months avoids relying on the amended wording. The Form 4 fee is charged per month: a three-month extension costs ₹3,000 on e-filing for a natural person, startup, small entity or educational institution and ₹12,000 for others, or ₹6,000 and ₹30,000 where expedited examination was requested. A Rule 138 extension, by contrast, costs ₹10,000 and ₹50,000 per month. Strategy for answering a report that follows a negative written opinion is covered in our guide to the negative PCT written opinion and the Indian FER.
Frequently Asked Questions
Yes, for a person resident in India, unless the invention was first filed outside India by a non-resident. A Division Bench of the Delhi High Court held that a PCT application filed at the Indian Patent Office counts as an application filed outside India. A resident must file in India six weeks earlier with no secrecy direction in force, or obtain a Form 25 permit first.
No. The 31-month period applies to applications filed on or after 15 March 2024, when the 2024 Rules took effect. For a national phase application, the filing date is the international filing date. Applications filed before that date keep the earlier 48-month period under a transitional provision.
Form 3 is due within six months of the actual date of filing in India. Later foreign filings are reported within three months of the First Examination Report, and any made after that, as a precaution, before grant. A fresh Form 3 directed by the Controller is due within two months; delay in filing Form 3 can be condoned by up to three months on Form 4.
Treat it as fixed. The Controller’s general correction power excludes the 31-month limit, and India has told WIPO that the PCT’s reinstatement procedure is incompatible with its law. Rule 138 lists no exclusions, but relying on it for national phase entry is a risk no docket should take.
Yes, where the international application was not filed or not published in English. A verified English translation of the description, claims, drawing text and abstract must be filed before the 31-month limit, with amended claims or annexes as applicable. Untranslated amendments are disregarded after an unanswered invitation.
Not under the Controller’s general correction power, which excludes it, and not by the three-month extension for answering the First Examination Report, which does not apply to it. Rule 138 lists no exclusions, but a missed request means the application is treated as withdrawn, so file Form 18 with Form 1 where both deadlines coincide.
Six months from the date the First Examination Report is issued, extendable once by three months on a Form 4 request, including where expedited examination was requested. Filing Form 4 within the six months is the safe course. An application not put in order within that period is deemed abandoned, so docket the date of issue, not receipt.
This article explains the law on PCT filing and national phase mistakes in India as at October 2026 and is for general information only. It is not legal advice. Government fees, forms, and procedures change; confirm current figures with the Indian Patent Office before you file. For advice on your specific invention, consult a registered patent agent.
Sources
- The Patents Act 1970, as amended (Sections 8, 21, 39, 40, 64, 118), IP India; Section 118 proviso inserted by the Jan Vishwas (Amendment of Provisions) Act 2026 and in force from 1 June 2026 under S.O. 2846(E).
- The Patents Rules 2003, consolidated (Rules 12, 20, 24B, 24C, 71, 137, 138), IP India, as amended by G.S.R. 211(E) of 15 March 2024.
- Patent Cooperation Treaty and Regulations under the PCT, in force from 1 January 2026, WIPO.
- PCT Reservations, Declarations, Notifications and Incompatibilities, status 3 September 2026, WIPO.
- Puneet Kaushik v Union of India, LPA 884/2013, 2014:DHC:7260-DB, 19 December 2014, Delhi High Court.