A patent is granted for an invention — a product or a process — that is new, involves an inventive step, and is capable of industrial application. It gives the patentee the right to prevent others from making, using, selling, offering for sale or importing the invention in India without authorisation, for twenty years from the date of filing.
Patent work is unusually front-loaded. What the specification says on the day it is filed sets the outer limit of what can ever be claimed, because no amendment may extend the scope of the claims beyond what was originally disclosed. For an applicant in Kolkata, this page sets out which office will handle the application, what the application has to survive, and which court hears an infringement action.
Which patent office handles a Kolkata application
- Appropriate office
- Patent Office (Head Office), Kolkata
- Territorial jurisdiction
- the rest of India — Bihar, Jharkhand, Odisha, West Bengal, Sikkim and the north-eastern states, and the Andaman and Nicobar Islands
- Determined by
- Residence, domicile or place of business of the applicant, or where the invention originated
- Statutory basis
- Rule 4, Patents Rules, 2003
- Office address
- Boudhik Sampada Bhawan, CP-2, Sector V, Salt Lake City, Kolkata 700 091
Under Rule 4 of the Patents Rules, 2003, the appropriate office is the head office or the branch office within whose territorial limits the applicant — or the first-named applicant where there are joint applicants — normally resides, is domiciled, or has a place of business. It may alternatively be the place from which the invention actually originated. Where the applicant has no domicile or place of business in India, it is the address for service given in the application.
An applicant based in Kolkata therefore files at the Patent Office (Head Office), Kolkata, which is both the office with jurisdiction and the head office of the Patent Office for the whole of India.
Two points catch applicants out. First, the patent split is not the same as the trade marks split — the two registries divide the country differently, so a business may deal with one city's office for its marks and another's for its patents. Second, once the appropriate office is fixed for a proceeding, it is not ordinarily changed afterwards.
How the firm acts for a client in Kolkata
Patent drafting, filing and prosecution are conducted electronically and hearings before the Controller are ordinarily held by video conference. The points below set out how the firm conducts a patent matter for a client based in Kolkata.
A specification is built from the inventor’s disclosure, the prior art, and the commercial objective. That is document and discussion work, conducted by call and email, and it does not depend on the drafter being in the same city as the inventor.
Applications, requests for examination, responses to the First Examination Report and pre-grant oppositions are filed through the CGPDTM portal at the Patent Office (Head Office), Kolkata.
Hearings on outstanding objections, and in opposition proceedings, are ordinarily listed and heard online.
Where an infringement or revocation action requires appearance before a court in West Bengal, the firm associates local counsel who appears on the record, and continues to conduct the matter itself.
What the firm handles in patent matters
- Patentability and prior-art searches
- Freedom to Operate (FTO) analysis — clearance searches before product launch or commercialisation
- Drafting of patent specifications and claims
- Prosecution of Indian and PCT national-phase applications
- Pre-grant and post-grant opposition
- Compulsory licensing and revocation matters
- Patent infringement, declaratory and groundless-threat actions
What can and cannot be patented
An invention must clear a positive test and avoid a list of statutory exclusions. In India the exclusions do a great deal of the work, particularly for software and for pharmaceutical inventions.
The three requirements
Sections 2(1)(j), 2(1)(ja) and 2(1)(ac)
- Novelty — the invention must not have been anticipated by publication or use anywhere in the world before the priority date
- Inventive step — a feature involving technical advance compared to existing knowledge, or having economic significance, and not obvious to a person skilled in the art
- Industrial application — capable of being made or used in an industry
- Sufficiency of disclosure — the specification must describe the invention fully enough for a skilled person to perform it, under Section 10
Statutory exclusions
Sections 3 and 4, Patents Act, 1970
- A mere discovery of a new form of a known substance that does not result in enhanced efficacy — Section 3(d), the provision applied in Novartis AG v Union of India, (2013) 6 SCC 1
- A mere discovery of a scientific principle, or the formulation of an abstract theory
- A computer programme per se, or an algorithm — Section 3(k)
- A mathematical or business method
- A method of agriculture or horticulture
- Methods of treatment of humans or animals — Section 3(i)
- Plants and animals in whole or any part thereof, other than micro-organisms
- Inventions relating to atomic energy — Section 4
Section 3(d) and Section 3(k) are the two exclusions that most often decide an Indian application. A software-implemented invention is not automatically excluded: what matters is whether the claim is to a computer programme as such, or to a technical effect achieved by it, and the specification has to be drafted with that distinction in view from the outset.
Provisional and complete specifications
An application may be filed with a provisional specification, which describes the invention but need not contain claims. It secures a priority date. A complete specification must then be filed within twelve months, failing which the application is deemed abandoned under Section 9(1).
The provisional route is useful where the invention is still developing, or where a disclosure is imminent — a conference paper, an investor presentation, a product launch. It is not a way of deferring the hard thinking. The complete specification may not travel beyond what the provisional disclosed; matter not fairly based on the provisional does not get the earlier date.
Publication is automatic. Under Section 11A the application is published after eighteen months from the priority date, unless early publication is requested. Examination is not automatic: a request for examination must be filed under Section 11B, and if it is not filed within the prescribed period the application is treated as withdrawn. This is the most common way a good Indian patent application is lost.
Documents required to file
- Provisional or complete specification, with claims, abstract and drawings where applicable
- Form 1 — application for grant of a patent, naming the applicant and the inventors
- Form 2 — the specification itself
- Form 3 — statement and undertaking regarding corresponding foreign applications, which must be kept updated during prosecution
- Form 5 — declaration as to inventorship, filed with a complete specification
- Form 26 — power of attorney, where a patent agent or advocate is appointed
- Proof of right to apply, where the applicant is not the inventor — typically an assignment from the inventors
- DPIIT startup recognition or Udyam registration, where the concessional fee is claimed
Form 3 is a continuing obligation, not a one-off filing. Failure to keep the Controller informed of corresponding foreign applications is a ground of revocation under Section 64(1)(m), and it has been litigated.
How an application proceeds
- 01 Patentability and prior-art search
A search of patent and non-patent literature to assess novelty and inventive step, and to shape the claims around what is actually available. A freedom-to-operate search answers a different question — whether making the product would infringe someone else’s rights — and is run separately where a launch is planned.
- 02 Drafting the specification
The specification describes the invention, the problem it solves and the best method of performing it, and sets out the claims that define the monopoly. Under Section 59, no amendment may extend the scope of the claims beyond what was disclosed as filed, which is why the drafting stage carries disproportionate weight.
- 03 Filing
The application is filed with a provisional or complete specification at the appropriate office. Where priority is claimed from an earlier application, or the application enters the national phase from a PCT application, the prescribed period runs from the priority date.
- 04 Publication
The application is published after eighteen months from the priority date under Section 11A. Early publication may be requested. From publication, the applicant has the privileges of a patentee, though no infringement action may be brought until grant.
- 05 Request for examination
Examination happens only on request, under Section 11B. If the request is not filed within the prescribed period, the application is treated as withdrawn. Expedited examination is available on specified grounds, including where the applicant is a startup or a small entity.
- 06 First Examination Report and reply
The Controller issues a First Examination Report setting out objections on patentability, sufficiency, clarity and form. All objections must be met and the application put in order for grant within the period prescribed by Rule 24B, which runs from the date of the report and is not open-ended.
- 07 Hearing, pre-grant opposition and grant
Where objections remain, the Controller may fix a hearing. Any person may file a pre-grant opposition under Section 25(1) after publication and before grant. If the application is in order, the patent is granted and published.
- 08 Post-grant obligations
A post-grant opposition may be filed by an interested person within twelve months of publication of grant, under Section 25(2). Renewal fees are payable annually from the third year. A statement of working must be filed in Form 27.
The deadlines that decide a patent application
Unlike trade marks, most patent deadlines are statutory and unforgiving. Missing any of the first four below usually ends the application.
| Step | Period | Basis |
|---|---|---|
| Complete specification after a provisional | Within twelve months | Section 9(1) |
| PCT national phase entry in India | Thirty-one months from the priority date | Rule 20(4)(i) |
| Publication of the application | Eighteen months from the priority date | Section 11A |
| Request for examination | Within the period prescribed by the Rules, failing which the application is treated as withdrawn | Section 11B |
| Putting the application in order for grant | Within the period prescribed, running from the First Examination Report | Rule 24B |
| Pre-grant opposition | After publication and before grant | Section 25(1) |
| Post-grant opposition | Within twelve months of publication of grant | Section 25(2) |
| Renewal fees | Annually, from the third year | Section 53 |
| Statement of working (Form 27) | As prescribed | Section 146 |
| Term of the patent | Twenty years from the date of filing | Section 53 |
The term runs from the date of filing, not the date of grant. Because examination and opposition consume years of that term, the commercial life of an Indian patent is generally materially shorter than twenty years.
Government fees for a patent application
| Matter | Natural person, startup or small entity | Others |
|---|---|---|
| Application for a patent (Form 1), e-filing | ₹1,600 | ₹8,000 |
| Request for examination (Form 18), e-filing | ₹4,000 | ₹20,000 |
| Request for expedited examination (Form 18A), e-filing | ₹8,000 | ₹60,000 |
| Pre-grant opposition (Form 7A) | No fee | No fee |
| Post-grant opposition (Form 7) | ₹2,400 | ₹12,000 |
| Renewal fees | Payable annually from the third year, on a rising scale | Payable annually from the third year, on a rising scale |
These are the statutory fees payable to the Patent Office under the First Schedule to the Patents Rules, 2003, as amended. Additional fees apply for specifications above thirty pages and for claims above ten, and renewal fees are payable annually from the third year. They are not the firm’s fees. Riva Legal Associates does not disclose its professional fees on this website; the fee for a particular matter is set out in the engagement letter before work begins. Figures are given for general information and are subject to amendment of the Rules.
After grant — keeping the patent alive and enforceable
An Indian patent carries continuing obligations that have no equivalent in most other jurisdictions. Two of them are grounds of revocation.
- Pay renewal fees annually from the third year under Section 53. A patent that lapses for non-payment may be restored on application within eighteen months, under Section 60.
- File the statement of working in Form 27 under Section 146. The requirement is statutory and applies to every granted patent.
- Keep Form 3 updated. Failure to disclose information about corresponding foreign applications is a ground of revocation under Section 64(1)(m).
- Be aware of compulsory licensing. Under Section 84, any interested person may apply after three years from grant where the reasonable requirements of the public have not been satisfied, the invention is not available at a reasonably affordable price, or it is not worked in India.
- Record assignments and licences. An assignment is not valid unless it is in writing and the agreement is reduced to a document embodying all the terms, and it is entered in the register under Section 68.
Where a patent dispute from Kolkata is heard
The Calcutta High Court exercises ordinary original civil jurisdiction. A suit for patent infringement arising in Kolkata may therefore be instituted before the High Court itself where the valuation of the suit exceeds the pecuniary limit fixed for the courts below. Below that limit it is filed before the Commercial Courts at Kolkata.
There is an important qualification. Where the defendant counterclaims for revocation of the patent, Section 104 of the Patents Act, 1970 requires the suit and the counterclaim to be transferred to the High Court for decision. In patent litigation a counterclaim for revocation is the norm rather than the exception, so a substantial proportion of infringement suits end up before the High Court whatever their valuation.
Revocation may also be sought independently under Section 64, by petition to the High Court, and appeals from the Controller lie to the High Court under Section 117A following the abolition of the Intellectual Property Appellate Board by the Tribunals Reforms Act, 2021. A patent suit of a specified value is a commercial dispute under the Commercial Courts Act, 2015.
One further provision is worth knowing before sending any letter. Under Section 106, a person threatened with proceedings for infringement may sue for a declaration that the threats are unjustifiable, and for an injunction and damages. A cease-and-desist letter written carelessly can therefore create the litigation it was meant to avoid.
The Calcutta High Court has constituted an Intellectual Property Rights Division, its Rules having been notified by gazette notification dated 20 September 2024. It is the third High Court in India to adopt dedicated IPD rules, after Delhi and Madras, and it hears IP suits alongside appeals and rectification matters transferred from the former Intellectual Property Appellate Board.
Where patent questions commonly arise in Kolkata
Kolkata is eastern India’s commercial centre, with a long-established engineering and heavy industry base, the national tea trade, leather and jute, and a substantial publishing and cultural economy. That shapes the patent work that comes out of the city.
- Heavy engineering and capital goods — mechanical and process inventions from an established industrial base, usually requiring both apparatus and method claims.
- Chemicals and pharmaceuticals — process and formulation claims, with a significant regional industry.
- Metallurgy and materials — processing technology serving the eastern mineral and steel belt.
- Agricultural and food-processing technology — machinery and processes for tea, jute and food industries.
- Leather processing technology — tanning and finishing processes and effluent treatment.
- Information technology — software-implemented inventions subject to Section 3(k).
Sector context is set out here to describe the local economy and to indicate where questions of this kind arise. It is not a statement about the firm’s clients or engagements.
Relevant statutory framework
- Patents Act, 1970
- Patents Rules, 2003
- Patent Cooperation Treaty (PCT)
- Commercial Courts Act, 2015
- Tribunals Reforms Act, 2021
- Code of Civil Procedure, 1908
Frequently asked questions
Which patent office has jurisdiction over a Kolkata applicant?
The Patent Office (Head Office), Kolkata. Under Rule 4 of the Patents Rules, 2003, the appropriate office is fixed by where the applicant resides, is domiciled or has a place of business, or by where the invention originated. That office has territorial jurisdiction over the rest of India — Bihar, Jharkhand, Odisha, West Bengal, Sikkim and the north-eastern states, and the Andaman and Nicobar Islands.
Is the patent office the same as the trade marks office?
No, and they divide the country differently. For trade marks a Kolkata applicant deals with the Trade Marks Registry, Kolkata; for patents, the Patent Office (Head Office), Kolkata. The same business can therefore have its marks and its patents handled by offices in two different cities. Both are under the Controller General of Patents, Designs and Trade Marks.
How long does it take to get a patent granted in Kolkata?
It varies widely with the technology, the objections raised, and whether expedited examination is available. Publication alone is at eighteen months from the priority date, and examination follows a request. Ordinary grant timelines are measured in years rather than months, and no timeline can be assured. The twenty-year term runs from the date of filing, not from grant.
Can software be patented in India?
A computer programme per se is excluded by Section 3(k) of the Patents Act, 1970. That is not a blanket bar on software-implemented inventions. Where the claimed invention produces a technical effect going beyond the normal interaction between the program and the computer, it may be patentable. Whether it does is decided on the claims and the specification, which is why drafting matters more here than almost anywhere else.
What is the difference between a provisional and a complete specification?
A provisional specification describes the invention and secures a priority date without requiring claims. A complete specification must follow within twelve months under Section 9(1), and it must define the claims. The complete specification cannot travel beyond what the provisional disclosed, so a thin provisional buys a date but not much protection.
What happens if the request for examination is not filed?
The application is treated as withdrawn. Examination is not automatic in India — it happens only on a request under Section 11B, filed within the prescribed period. This is one of the most common ways an otherwise sound application is lost, and it is not curable.
Does an Indian patent give protection abroad?
No. A patent is territorial. Protection outside India requires filing in each country or region of interest, commonly through the Patent Cooperation Treaty, which preserves a priority date across member states while national-phase decisions are made. The firm handles Indian filings and national-phase entries directly, and coordinates foreign filings through associate agents abroad.
Should a patentability search be done before filing?
It is generally sensible. A search will not guarantee grant, because the Controller may find art the search did not, but it informs two commercial decisions: whether to spend on the application at all, and how the claims should be framed to sit clear of what is already published.
Can the firm act in a Kolkata patent matter from Jaipur?
Drafting, filing and prosecution are conducted electronically at the Patent Office (Head Office), Kolkata, and hearings before the Controller are ordinarily held by video conference, so this work does not depend on the location of the advocate. Where an infringement or revocation action requires appearance before a court in West Bengal, the firm associates local counsel who appears on the record. The firm’s chambers are in Jaipur.
Riva Legal Associates works from a single chambers in Jaipur, Rajasthan and does not maintain an office in Kolkata. Matters requiring appearance before a court in West Bengal are handled in association with local counsel.
This page is published for general information about the law and procedure that applies to a business in Kolkata. It is not legal advice, an advertisement, or a solicitation, and it should not be relied upon as a statement of the law applicable to any particular matter. For advice on a specific matter, please contact the firm or consult a qualified advocate.
Other intellectual property matters in Kolkata
Patents in other cities
The firm accepts matters from clients across India, in association with local counsel where appearance in another state is required.
Discuss a matter in this area
Phone, WhatsApp, email, or the form. An initial consultation is arranged on request.