Patent Cooperation Treaty in India: Lifecycle Guide

The Patent Cooperation Treaty (PCT) is a 1970 treaty, in force in 158 contracting states as of March 2026, that lets you file one international patent application and defer country-by-country filing decisions. The Patent Cooperation Treaty in India is administered through the Indian Patent Office, which acts as Receiving Office, International Searching Authority, International Preliminary Examining Authority, Designated Office, and Elected Office. India acceded on 7 December 1998.

This guide covers the Patent Cooperation Treaty as it operates for India. The treaty itself applies to all 158 contracting states; the procedural detail in this article reflects the Patents Act 1970, the Patents Rules 2003 as amended through 15 March 2024, and the PCT Regulations in force from 1 January 2026. Where the article describes international-phase mechanics, the framing is jurisdiction-neutral; where it covers India-specific entry, filing, and forms, the framing is India-specific.

For Indian inventors, startups, foreign IP counsel, and in-house teams managing Indian patent portfolios, this article is the practical lifecycle reference for the Patent Cooperation Treaty as it operates for India. For depth on entering India via PCT national phase, see our PCT national phase entry guide. For depth on filing PCT internationally from India, see our PCT international filing guide.

Quick Reference

Verified as of April 2026.

• 158 PCT Contracting States as of March 2026; India acceded 7 December 1998.
• Priority deadline: 12 months from first filing.
• Restoration of priority in the international phase: up to 14 months under PCT Rule 26bis.3.
• India PCT deadline (national phase entry): 31 months from priority date (the PCT 31 month deadline India applies under both Article 22 and Article 39 routes).
• Request for Examination on Form 18: 31 months from priority for applications filed on or after 15 March 2024.
• PCT Rule 49.6 India: no reinstatement of rights at national phase.
• Indian Patent Office is RO/IN, ISA, IPEA, Designated Office, and Elected Office.
• Filing fee anchors: INR 1,600 (electronic, natural person / startup / small entity / educational institution); INR 8,000 (electronic, other applicants).

Lifecycle at a glance

Related PCT guides

Pre-PCT decision: Paris Convention vs PCT comparison, Foreign Filing Licence under Section 39.

International phase strategy: International phase vs national phase, India as ISA, Article 19 vs Article 34 amendments, Chapter II demand strategy.

Filing PCT from India: PCT international filing from India.

Entering India via PCT: PCT national phase entry in India, PCT national phase amendments, Unity of invention and divisionals, Negative PCT Written Opinion at FER.

Deadlines and risk: Missed 12-month priority deadline, Late national phase entry global framework, Late national phase entry in India, Common PCT filing mistakes.

Cost: PCT national phase fees in India. Tool: PCT national phase calculator.

How the PCT works: international phase to national phase

The Patent Cooperation Treaty creates a single procedural track that sits between an applicant’s first filing and the patent granted in each country where protection is finally sought. There is no “international patent” at the end of it; the PCT does not grant a patent. What it does is consolidate the early steps, so that the country-by-country filing decision can be deferred for 18 or 19 months beyond the 12-month Paris Convention priority window. The applicant gets one international search, one international publication, and one optional preliminary examination, and uses that consolidated record to decide which national markets justify separate national prosecution.

The lifecycle has two phases. The international phase begins when an applicant files an international application with a Receiving Office. Under PCT Article 11(3), an international application that has been accorded an international filing date has the effect of a regular national application in each designated state as of that date. An International Searching Authority then conducts a prior-art search and issues an International Search Report (ISR) under PCT Article 18 and a written opinion on patentability under PCT Rule 43bis.1. The application is published by WIPO at 18 months from the priority date under PCT Article 21(2)(a). Once the ISR is transmitted, the applicant has two months from the date of transmittal, or 16 months from the priority date (whichever expires later) to file claim amendments with the International Bureau under PCT Article 19, per PCT Rule 46.1.

A Demand for international preliminary examination may be filed under PCT Article 31. The deadline is set by PCT Rule 54bis.1: whichever is later of three months from ISR transmittal or 22 months from the priority date. A Demand triggers a further round of substantive examination by an International Preliminary Examining Authority and a further opportunity to amend the description, claims, and drawings under PCT Article 34. The IPER (International Preliminary Examination Report) issued by the IPEA travels with the application into the national phase.

There are two routes into the national phase. If no Chapter II Demand is filed, the applicant enters national phase under PCT Article 22 in every designated state. If a Demand is filed and elections are made, entry is governed by PCT Article 39 in every elected state. India’s national-phase deadline is 31 months from the priority date under both routes. Rule 20(4)(i) of the Patents Rules 2003 fixes the deadline by reference to the priority date for any application under Section 7(1A); PCT Article 22(3) and PCT Article 39(1)(b) parallel each other in authorising national law to set time limits later than the 30-month treaty defaults, which India’s 31-month rule does. The operational difference between the two routes is what the applicant carries into national phase: ISR and written opinion under Article 22, or ISR and IPER under Article 39. The deadline arithmetic is identical for India. For the international-vs-national-phase distinction in jurisdiction-neutral terms, see our explainer on the international and national phases.

The PCT operates alongside several regional patent systems, including the European Patent Convention, the African Regional Intellectual Property Organization (ARIPO) Harare Protocol, the Eurasian Patent Convention, and the African Intellectual Property Organization (OAPI) Bangui Agreement. A PCT international application may designate a regional patent system rather than (or in addition to) individual national designations. India is not party to any regional patent system, so designating India in a PCT request is always a national designation processed by the IPO.

The national phase begins when the applicant enters each desired country, supplies the prescribed national fee, files any required translation, and submits the country’s prescribed national-phase forms. From this point onward, examination, prosecution, grant, and post-grant procedures are governed by national law. In India, that means the Patents Act 1970, the Patents Rules 2003, and the prosecution practice followed by the Indian Patent Office. Substantive examination begins only when a Request for Examination has been filed and the Controller refers the application to an examiner. For the broader context of how Indian patent law treats applications generally, see our overview of patent law in India.

India’s five roles in the PCT

The Indian Patent Office’s place in the PCT system is unusual in that the same office acts in five distinct capacities depending on the applicant’s choices and the procedural posture. Foreign counsel coming into India for the first time often encounter the IPO only as the Designated Office at national phase entry, and miss that the same office also serves as the Receiving Office for Indian-resident applicants and as a competent ISA and IPEA for international-phase work.

1. Receiving Office for India (RO/IN). Under PCT Article 10, the IPO acts as the Receiving Office for international applications filed by residents and nationals of India. An Indian-resident applicant has the choice of filing the international application at RO/IN or at the International Bureau in Geneva (RO/IB), subject to the Section 39 foreign-filing-licence requirements covered below. For the depth on RO/IN versus RO/IB selection and Section 39 clearance, see our PCT international filing from India guide.

2. International Searching Authority (ISA). The IPO has been appointed by the PCT Assembly as a competent International Searching Authority. Whether IPO is selected as the ISA in a given international application depends on the Receiving Office’s competent-authority list. For an Indian-resident application filed at RO/IN, the IPO is one of the available ISAs alongside other appointed authorities. For the strategic considerations of choosing IPO as the ISA, see our India as ISA designation guide.

3. International Preliminary Examining Authority (IPEA). Where an applicant files a Chapter II Demand under PCT Article 31, an IPEA conducts the international preliminary examination and issues the IPER. The IPO is an appointed IPEA. The choice of IPEA, like the choice of ISA, depends on the competent-authority list applicable to the case. For the decision-frame on when to file a Chapter II Demand and which IPEA fits a given case, see our Chapter II Demand strategy guide.

4. Designated Office. Where an international application designates India and the applicant enters Indian national phase under PCT Article 22, the IPO acts as Designated Office. Under Section 7(1A) of the Patents Act 1970, every PCT international application designating India is treated as an application under the Patents Act once the applicant completes Indian national phase entry within the prescribed timeline. Under Section 138(4), the title, description, claims, abstract, and drawings of the international application are taken as the complete specification for purposes of Indian law. Under Section 138(5), the international filing date becomes the filing date of the application processed by the IPO as Designated Office.

5. Elected Office. Where the applicant has filed a Chapter II Demand and elected India, the IPO acts as Elected Office at national phase entry under PCT Article 39. The Indian deadline is 31 months from the priority date under both routes; the only operational difference at entry is whether the applicant carries the IPER alongside the ISR and written opinion.

The combined effect of Sections 7(1A), 138(4) and 138(5) is that, once the corresponding national-phase application is on file at the IPO, the application processed in India carries the international filing date as its actual filing date in India, the international application’s contents as the complete specification, and the priority claim made in the international phase. The IPO does not re-examine the formality requirements that were settled internationally under Article 11 and Article 14. What the IPO does examine is the substantive patentability under Indian law, the formality requirements specific to Indian filings (Form 1 application particulars, Form 3 disclosure under Section 8, Form 5 declaration of inventorship), and any divisional or amendment filings made under the Patents Act after entry.

Designating India is not the same as filing in India.

A common misconception among foreign applicants is that designating India in the PCT request, by itself, secures patent rights in India. It does not. The Section 7(1A) deeming provision (the statutory rule treating a designating PCT international application as an application under the Patents Act) activates only when the applicant completes Indian national phase entry before the Controller within the 31-month deadline. Without that entry, the effect of the international application in India ceases by operation of PCT Article 24(1)(iii), which provides that the effect of the international application under Article 11(3) ceases in any designated state if the applicant fails to perform the acts referred to in Article 22 within the applicable time limit.

Practically, this means three things. First, the 31-month deadline is the activation deadline, not a procedural courtesy. Second, the international filing date is preserved in India only where the corresponding national-phase application is filed in time and in proper form. Third, the contents of the international application become the Indian complete specification only after national-phase filing under Section 138(4); before filing, India is merely a designated state on the WIPO record.

For the institutional roles described above, the WIPO PCT Applicant’s Guide India chapter is the authoritative source.

Plan your India entry now.

Use the national phase deadline calculator to compute the 31-month deadline and the IPO fees for a specific case in seconds.

Filing PCT from India

For Indian residents, the PCT route begins with two distinct decisions: where to file the international application, and whether the Section 39 foreign-filing-licence regime requires action before any filing outside India.

Indian-resident PCT filings typically start from a first filing already made in India under Section 7. The PCT international application is then filed within the 12-month Paris Convention priority period under PCT Article 8, claiming priority from the first Indian filing. Where there is no first filing in India and the applicant intends to file PCT directly, Section 39 compliance is engaged at the international filing stage rather than retrospectively.

Section 39 foreign-filing licence. Under Section 39(1) of the Patents Act 1970, no person resident in India shall, except under the authority of a written permit granted by the Controller, make or cause to be made any application outside India for a patent for an invention, unless an application for the same invention has been made in India not less than six weeks before the application outside India and no Section 35 secrecy direction is in force. The “outside India” framing reaches a PCT international application filed at the International Bureau in Geneva (RO/IB), so the Section 39 regime is engaged whenever an Indian resident considers filing PCT directly with WIPO instead of with RO/IN. The permit is requested on Form 25. In practice, Section 39 analysis should be completed before selecting RO/IN or RO/IB, because Indian-resident PCT filing raises foreign-filing compliance questions that are better resolved before the international filing is made. For the depth on Section 39 compliance and the foreign-filing-licence procedure, see our foreign filing licence guide.

Choice of Receiving Office: RO/IN or RO/IB. Once Section 39 is cleared, the applicant chooses where to file. For an Indian-resident applicant, both RO/IN and RO/IB are competent Receiving Offices under PCT Rule 19.1, and the applicant may elect either at the time of filing. The choice has practical consequences: the language of filing, the available ISAs, the fee currency, and the routing of the priority document. For the comparative analysis of RO/IN vs RO/IB and the practical considerations that drive the choice in cross-border practice, see our PCT filing from India guide.

International Searching Authority selection. The Receiving Office’s competent-authority list determines the ISAs available to the applicant. For an Indian-resident filing at RO/IN, the IPO is one of the available ISAs alongside others appointed for India. Each ISA has different fee structures, search practices, and turnaround characteristics. The choice influences both cost and the substantive value of the ISR for downstream prosecution in target jurisdictions. For the practitioner-grade analysis of ISA choice from India, see our India as ISA designation guide.

Article 19 amendments to claims. Once the ISR is transmitted, the applicant has two months from the date of transmittal, or 16 months from priority (whichever expires later), to file claim amendments with the International Bureau under PCT Article 19, per PCT Rule 46.1. Article 19 amendments are limited to the claims and may be accompanied by a brief statement, not exceeding 500 words in English, explaining the amendments. The amendments are published with the international application. For the strategic comparison of Article 19 versus Article 34 amendments, see our PCT amendment guide for Article 19 and Article 34.

Chapter II Demand and Article 34 amendments. Where the written opinion of the ISA raises objections the applicant wishes to address before national phase, a Chapter II Demand may be filed under PCT Article 31. The Demand triggers an international preliminary examination by the chosen IPEA, with the deadline set by PCT Rule 54bis.1 (whichever is later of three months from ISR transmittal or 22 months from priority). The applicant may amend the description, claims, and drawings under PCT Article 34 during the preliminary examination. The IPER is then transmitted to elected offices and travels with the application into national phase. For the decision-frame on when a Chapter II Demand is worth filing and which IPEA fits a given case, see our Chapter II Demand strategy guide.

Strategy in summary. The international phase work an Indian-resident applicant does between filing and national-phase entry shapes the downstream prosecution. A favourable ISR with no Article 34 amendments creates a different prosecution profile from a negative written opinion that is reshaped by Chapter II amendments. The intermediate decisions (where to file, which ISA, whether to amend, whether to Demand Chapter II) are connected and benefit from being made together rather than in sequence. PCT applicants who select India as the ISA or IPEA also become eligible to request expedited examination under Rule 24C at national phase entry, which can compress the wait for the First Examination Report substantially; see our expedited examination in India guide for the Form 18A eligibility framework. The depth on each decision is in the linked guide, with the international filing from India guide as the practical starting point for the full procedural detail.

Entering India via PCT national phase

Foreign applicants enter India via PCT national phase by filing the corresponding national-phase application before the 31-month deadline from the priority date, paying the prescribed national fee, and supplying any required translation. The IPO acts as Designated Office (under Article 22) or Elected Office (under Article 39) and processes the application as if it had been filed nationally on the international filing date.

The entry filing is made on Form 1, supplemented by Form 3 (Section 8 statement and undertaking), Form 5 (declaration as to inventorship), Form 18 (Request for Examination), and where an agent is appointed, Form 26 (authorisation of patent agent). If the international application was not filed in English, an English translation of the description, claims, abstract, and any text matter in drawings is required at entry under Rule 20(3) of the Patents Rules 2003. The translation is verified as correct and complete by the applicant or duly authorised person.

India does not permit Rule 49.6 reinstatement at national phase: the WIPO PCT Applicant’s Guide India chapter answers “No” to the question of whether the office permits reinstatement of rights for failure to perform the acts referred to in PCT Article 22. The Indian late-entry routes depend on Rule 138 of the Patents Rules 2003 (Controller’s discretionary six-month extension on Form 4) and on the case-law developed around Rule 22 and Rule 138.

The depth on entry mechanics, document requirements, fee structure, RFE timing, and prosecution practice is in our PCT national phase entry in India guide, which is written for foreign counsel preparing an Indian national phase entry. Adjacent topics covered in dedicated guides include: amendments at national phase, unity of invention and divisionals, and responding to a negative PCT written opinion at the FER stage.

Practitioner note: link the entry deadline and the RFE deadline.

For India, docketing should treat the 31-month national phase entry deadline and the Form 18 RFE deadline (also 31 months for applications filed on or after 15 March 2024) as linked critical dates. Where both deadlines fall together, the RFE is best prepared alongside the entry documents rather than treated as a later prosecution step.

Choosing your route: PCT or Paris Convention

An applicant with a first filing in one country has two routes to seek patent protection in another. Under the Paris Convention for the Protection of Industrial Property, a separate national application may be filed in any other Paris country within 12 months of the first filing, claiming priority from that first filing. Under the PCT, a single international application is filed within the same 12-month priority period, and the applicant then has up to a further 18 or 19 months to enter national phase in the desired countries.

The decision turns on three considerations: the number of countries under serious consideration, the cash-flow profile the applicant prefers, and the value of the international search and optional preliminary examination as inputs to the eventual national-phase decision. A small number of well-defined target countries can often be served efficiently by direct Paris filings; a broad or undecided set of countries is typically better served by the PCT. The PCT’s deferred-decision feature has cost: an applicant who would otherwise file in only one or two countries adds the international fees and ISA fees on top of the eventual national costs. The default heuristic: direct Paris filings often come out lower-cost where the target list is one or two well-defined countries, while the PCT’s deferred-decision option typically justifies the additional international and ISA fees where the target list is three or more or geography remains undecided. The Paris Convention versus PCT comparison guide sets out the cost arithmetic and the practical considerations in detail.

Missed deadlines and risk in PCT for India

Three deadlines are critical to PCT applications involving India, and each has a distinct restoration regime.

Missed 12-month priority deadline. Where the international application is filed after the 12-month priority window, the applicant may, under PCT Rule 26bis.3, request restoration of the right of priority from the Receiving Office, provided the international application is filed within 14 months from the priority date and the failure to meet the 12-month deadline was unintentional or occurred in spite of due care (the applicable standard varies by Receiving Office). For the depth on the restoration mechanism, the unintentional vs due-care standards, and the procedural requirements at RO/IN and RO/IB, see our missed 12-month PCT deadline guide.

Missed 31-month national phase deadline (India). India does not permit reinstatement under PCT Rule 49.6. Any delayed national phase filing arguments under Indian law are highly fact-specific and have been litigated under Rule 22, Rule 138, and related case law (including Nokia (2010), Tryton (2014), Diebold (2022), and Humanity Life Extension (2023)). Applicants should treat the 31-month deadline as a hard deadline. For the doctrinal analysis and the practical filing path, see our late PCT national phase entry in India guide. For the cross-jurisdictional context covering automatic-extension countries, petition-based reinstatement countries, and no-late-entry countries, see our global late national phase entry guide.

Common procedural mistakes at filing and at national phase. Beyond deadline-driven risk, foreign-applicant national-phase filings often see procedural errors in Form 3 disclosure under Section 8, in the verified-translation requirement under Rule 20(3), and in entity-classification fees under the First Schedule. Each error has a specific cure with a distinct cost. For the catalogue of common errors and their cures, see our PCT filing mistakes in India guide.

How much PCT filing costs in India

The cost of PCT national phase entry in India is determined by the First Schedule of the Patents Rules 2003 and is sensitive to the applicant’s category, the filing mode (electronic versus paper), and the number of claims and specification pages.

For an application up to 30 pages with up to 10 claims, the filing fee anchors are: INR 1,600 for electronic filing by a natural person, startup, small entity, or educational institution; INR 1,750 for paper filing in the same category; INR 8,000 for electronic filing by other applicants; and INR 8,800 for paper filing by other applicants. Each additional sheet beyond 30 and each additional claim beyond 10 carries a separate per-unit charge under the same Schedule, with sequence-listing pages charged differently and capped. The Request for Examination on Form 18 carries a separate prescribed fee.

For the worked scenarios, the entity-classification analysis, and the claim-and-page surcharge tables in detail, see our PCT national phase fees in India guide. For an instant calculation that accounts for entity, claims, and pages in a specific case, use the PCT national phase calculator. For the broader context of patent filing and prosecution costs in India outside the PCT route, see our overview of patent filing and prosecution costs in India.

The official First Schedule of fees is published by the Indian Patent Office. *Verified as of April 2026.* Fees should always be verified against the latest First Schedule and WIPO fee schedules before filing.

Where to start: action paths by reader profile

Different readers approach the PCT lifecycle with different next actions in mind. The action paths below sort by reader profile.

Indian inventor or startup considering PCT for the first time. Begin with the Paris Convention versus PCT comparison to settle the route choice, then read the PCT international filing guide for the procedural detail. The Section 39 foreign filing licence guide covers compliance, which must be cleared before any foreign filing.

Indian corporate or in-house team filing PCT for a cross-border portfolio. The PCT international filing from India guide is the primary reference. Pair it with India as ISA designation, Article 19 vs Article 34 amendment timing, and Chapter II Demand strategy for the international-phase strategy decisions.

Foreign in-house counsel docketing an Indian national phase deadline. The PCT national phase entry in India guide is the primary reference. The national phase calculator computes the 31-month deadline and the IPO fee for a specific case in seconds. For risk on missed deadlines, the Indian late entry guide and the missed 12-month deadline guide are the operational references.

Foreign IP firm managing an Indian portfolio. The same set as in-house counsel, plus the deeper Indian national-phase prosecution articles: national phase amendments, unity of invention and divisionals, negative PCT written opinion at FER, and the common PCT filing mistakes in India guide.

Frequently asked questions about PCT in India

Disclaimer

This article is general practitioner guidance for the Patent Cooperation Treaty as it operates for India. It is not legal advice. Statutory references are correct as of April 2026; the PCT Regulations apply as in force from 1 January 2026. For case-specific advice, consult a registered Indian patent agent.