Navigating International Patent Filing: The Advantages of the PCT Route

For any inventor or business looking to protect an innovation across multiple countries, the first instinct might be to file separate patent applications in each target market. That approach is not only expensive but logistically complex – different languages, different deadlines, different procedural rules. The Patent Cooperation Treaty (PCT) was designed precisely to solve this problem. Administered by the World Intellectual Property Organization (WIPO), the PCT offers a single, unified filing route that simultaneously covers over 150 countries – and for Indian inventors, it has been a game-changer since India joined the treaty in December 1998.

What the PCT actually does (and what it doesn’t) 🔗

The PCT is an international treaty that lets you file one “international application” to seek patent protection in multiple countries at once, instead of filing separate national applications in each jurisdiction. According to WIPO, once you file this single application with a receiving office in one language and pay one consolidated set of fees, you have effectively initiated the patent process across all PCT contracting states simultaneously.

There’s one critical point to get right upfront: the PCT does not grant an international patent. No such thing exists. The PCT establishes a filing date in all contracting states, but the actual decision to grant or reject a patent always rests with each national or regional patent office. What the PCT does is create a streamlined, predictable international procedure that feeds into those national decisions – essentially buying you time and information before you commit to the expensive national filing stage.

The two phases of a PCT application 🔗

A PCT application moves through two distinct phases: the international phase and the national phase.

The international phase 🔗

The international phase begins the moment you file your PCT application. This phase has several key steps that unfold over roughly 18-30 months:

Filing: The application is submitted to a Receiving Office (RO) – this can be your national patent office or WIPO’s International Bureau directly. Indian applicants typically file through the Indian Patent Office (IPO), which acts as the Receiving Office.

International Search: An International Searching Authority (ISA) – one of the world’s major patent offices such as the European Patent Office, the US Patent and Trademark Office, or the Indian Patent Office – conducts a prior art search. The ISA prepares an International Search Report (ISR) and a Written Opinion (WOISA), which together provide an initial, non-binding assessment of whether your invention appears novel, involves an inventive step, and is industrially applicable. This report is one of the PCT’s most valuable outputs – it tells you where your application stands before you spend money entering national phases.

International Publication: Eighteen months after the priority date, WIPO publishes the PCT application along with the ISR and the ISA’s written opinion. This public record can serve as a deterrent to competitors and signals that you are actively pursuing protection.

Optional International Preliminary Examination (Chapter II): At this stage, an applicant can optionally request an International Preliminary Examining Authority (IPEA) to conduct a further patentability analysis. This is particularly useful if the ISA’s Written Opinion raised objections, because Chapter II allows the applicant to submit amendments and arguments and even interact with the examiner before entering national phases – something that Chapter I (no demand filed) does not allow. The result is an International Preliminary Report on Patentability (IPRP), which, if positive, can significantly ease examination in the national phase and even accelerate prosecution through mechanisms like the Patent Prosecution Highway (PPH).

The national phase 🔗

After the international phase concludes, the applicant enters the national (or regional) phase in whichever countries they choose. In India, this deadline is 31 months from the priority date, and a 2024 amendment even allows for a further 6-month extension upon payment of an additional fee. Once a PCT application enters the Indian national phase, the Indian Patent Office treats it as a regular Indian patent application examined under the Patents Act, 1970. Each country then applies its own national laws to determine whether to grant the patent – the PCT work done internationally simply provides a strong starting foundation.

Why the PCT route is strategically advantageous 🔗

One application, global effect 🔗

A PCT application has the same legal effect as a regular national application in each designated contracting state as of the PCT filing date. Without this system, an inventor would need to prepare and file separate applications – each in a different language, under different procedural rules, within independent deadlines – in every country of interest. The PCT collapses all of that into a single filing event, dramatically reducing administrative complexity.

Extended decision-making window 🔗

Perhaps the most strategically valuable benefit is time. The PCT system allows an applicant to defer the decision of where to seek actual protection for up to 30-31 months from the earliest priority date. This window allows inventors to conduct market research, assess commercial viability, and evaluate the strength of their invention in different regions before committing to the high costs of national phase filings. If, during this time, you determine that a particular market is not worth pursuing, you simply do not enter the national phase there – and you have saved the cost of a full national filing.

Cost efficiency 🔗

Upfront, a PCT application involves the international filing fee, a search fee, and a transmittal fee. These are real costs, but they compare favourably against the cumulative expense of filing independent national applications in multiple jurisdictions simultaneously – especially when you factor in translation costs, local attorney fees, and individual filing charges in each country. WIPO also offers a 90% fee reduction on certain PCT fees for natural persons from developing countries, which makes the route meaningfully more accessible for individual Indian inventors and startups. Additionally, in several national offices, the filing fees for applications coming through the PCT route are actually lower than for direct national applications, in recognition of the examination work already completed during the international phase.

Informed patent strategy through the ISR 🔗

The International Search Report is not just a procedural document – it is a strategic intelligence tool. After receiving the ISR and Written Opinion, the applicant can file claim amendments within 2 months from the ISR date or within 16 months from the priority date, whichever is later. This means you can refine your claims based on actual prior art findings before the application is published and before national offices examine it – giving you a stronger application to take into the national phase.

Avoiding duplication of effort 🔗

Without the PCT, each national office would independently search and examine the same invention from scratch. The PCT’s international search and examination results are shared across all designated offices, allowing many national offices to rely on or take guidance from the IPRP. This reduces redundant work, can accelerate grant timelines, and creates a more consistent global patenting experience.

How Indian inventors use the PCT route 🔗

India joined the PCT in December 1998, and by 2024, India ranked 6th globally in the number of patent filings, with over 100,000 grants in a single year – a remarkable milestone for a country that entered the international patent system through the PCT route relatively recently. Indian residents who wish to file abroad must first obtain a Foreign Filing Licence (FFL) from the Indian Patent Office before submitting a PCT application, as required under Section 39 of the Patents Act, 1970.

Once the FFL is obtained, an Indian applicant can file a PCT application either directly with the Indian Patent Office as the Receiving Office or with WIPO’s International Bureau. If a patent application was first filed in India, a PCT application can be filed within the same 12-month priority period to gain a further 18 months of international phase time, effectively extending the window before national phase costs begin.

It is equally important to note that when foreign applicants want to protect their inventions in India through the PCT route, they can designate India in their PCT application. Once the 31-month national phase deadline approaches, they enter the Indian national phase, and the application is examined under the Patents Act, 1970, just like any domestic application.

PCT vs. direct national filing: a practical comparison 🔗

Filing directly in each country under the Paris Convention route means you must commit to each jurisdiction within 12 months of your priority date – with separate attorneys, translations, and fees for each. The PCT route extends this commitment window to 30-31 months, gives you a centralised search report, and allows you to make global decisions from a single point of control. For inventors who are uncertain about which markets will matter most commercially, the PCT’s deferral mechanism alone justifies the route. For large portfolios or high-value inventions, the consolidated procedural work and shared ISR results translate into significant long-term savings.

Limitations to keep in mind 🔗

The PCT is not without limitations. The international phase does not guarantee a patent – every national office retains full authority to reject your application under its own law. During the national phase in India, the application must comply with the Indian Patent Act in full, including its specific exclusions under Sections 3 and 4, which cover subject matters like methods of treatment, mathematical methods, and inventions contrary to public order. A positive IPRP is helpful but not binding on national offices. Also, the initial PCT costs, combined with eventual national phase fees across multiple countries, can still amount to a significant investment – the PCT delays costs, it does not eliminate them.

What do you think? If you were an early-stage startup with a novel technology but limited funding, how would you decide which countries to enter at the national phase after receiving a PCT search report? And given that the IPRP is non-binding, do you think national patent offices should give it more weight to create greater consistency in international patent outcomes?

References

1. https://www.wipo.int/en/web/pct-system
2. https://www.wipo.int/pct/en/faqs/faqs.html
3. https://en.wikipedia.org/wiki/Patent_Cooperation_Treaty
4. https://www.mewburn.com/law-practice-library/international-pct-patent-applications-the-basics
5. https://patentpc.com/blog/understanding-the-patent-cooperation-treaty-pct-process
6. https://www.wilsongunn.com/resource/ip-insights/deciding-whether-or-not-to-request-a-chapter-ii-demand-for-international-preliminary-examination
7. https://www.rkdewan.com/blogs/pct-national-phase-india-filing/
8. https://www.mondaq.com/india/patent/1527056/the-patent-cooperation-treaty-pct-and-global-patent-filing-strategy-for-indian-inventors
9. https://www.globalpatentfiling.com/blog/patent-proceedings-international-stage-pct-chapter-i-and-pct-chapter-ii
10. https://www.lexology.com/library/detail.aspx?g=55338093-cd8d-4789-a826-1e9a8d2177d7
11. https://www.taxtmi.com/article/detailed?id=13476