Form 18 in India: request for examination, fees and deadline

Filing a patent application in India does not start examination. The Patent Office examines an application only after someone asks for it by filing Form 18, the request for examination. Miss the deadline and the application is treated as withdrawn, however good the invention is. This guide explains the deadline, fee, process and the faster Form 18A route.

What is Form 18?

Form 18 is the request for examination under Section 11B of the Patents Act, 1970 and Rule 24B of the Patents Rules, 2003. Once it is filed (and the application is published), the Controller sends the application to an examiner, who checks whether the invention is new, inventive, industrially applicable and not excluded by Sections 3 and 4. The result is the First Examination Report (FER).

Form 18 deadline: 31 months

The request must be filed within 31 months from the priority date or the filing date, whichever is earlier. This limit was cut from 48 months by the Patents (Amendment) Rules, 2024, in force from 15 March 2024.

If no request is filed in time, the application is treated as withdrawn (Section 11B(4)). There is no fee to buy back a missed deadline, so docket it the day you file. Our free patent deadline calculator works out the date for you.

Form 18 fees (e-filing)

Physical (paper) filing costs 10% more. For the full cost from filing to grant, see patent filing cost in India or use the patent fee calculator.

Who can file Form 18?

The applicant, or any other interested person (Section 11B(1)). In practice the applicant's registered patent agent files it online with the application or soon after. A competitor can also request examination of your application, for example to get certainty about whether it will be granted.

When should you file it?

• With the complete specification, if you want the fastest possible grant. There is no benefit in waiting unless you are still deciding whether the invention is worth the cost.
• Later, within 31 months, if you want to defer spending while you test the market or raise funds. The trade-off is a later grant, and your 20-year term still runs from the filing date.
• Examination only starts once the application is published (18 months from priority, or about a month after a Form 9 early-publication request).

Form 18A: expedited examination

Form 18A asks for expedited examination under Rule 24C. Applications on this track are taken up much sooner than the normal queue, and many are granted within about a year. It is open to:

• startups recognised by DPIIT;
• small entities (MSMEs under the MSMED Act limits);
• women applicants (at least one applicant who is a natural person is female);
• government departments, government companies and institutions established or substantially financed by the government;
• applicants who chose the Indian Patent Office as their International Searching or Preliminary Examining Authority in a PCT application; and
• applicants covered by an arrangement between the Indian Patent Office and a foreign patent office.

Form 18A must be filed online, and the application must be published, so it is usually filed together with Form 9 (early publication). Expect the examination report and reply deadlines to come quickly; you need a well-drafted specification ready to defend.

What happens after you file Form 18

1. The application waits until it is published and its turn in the examination queue comes.
2. An examiner searches the prior art and reports to the Controller.
3. The Patent Office issues the First Examination Report (FER) listing objections.
4. You file a reply within 6 months of the FER (extendable by 3 months), amending the claims where needed. See patent examination reply.
5. If objections remain, a hearing is scheduled; otherwise the patent is granted.

How long each stage takes is explained in how long a patent takes in India.

Common mistakes

• Counting 31 months from the complete specification instead of the provisional (priority) date.
• Assuming the patent agent files Form 18 automatically: confirm it in writing.
• Paying the large-entity fee when you qualify as a startup or small entity (keep your DPIIT or Udyam certificate ready).
• Filing Form 18A without Form 9, which delays expedited examination until normal publication.

This guide is general information, not legal or tax advice. Rules and thresholds change; speak to an expert about your situation.