Form 27 Working Statement: The 3-Year Block Table

How-To · Patent Compliance

Updated for 2026 · Claw Editorial

Missing a Form 27 deadline is easy to do and costly to fix, because the due date is not printed on the patent certificate. It depends on the year of grant and on a three-year block that started only after the 2024 rule change. This guide shows how to work out the right block for each patent, gives a grant-year to due-date table, and explains how to keep the whole portfolio on one calendar. Last verified October 2026.

01Why Form 27 is easy to miss

Form 27 is the statement in which a patentee, and every licensee, tells the Controller whether the patented invention has been worked in India. It is a legal duty under Section 146 of the Patents Act, 1970, and it sits quietly in the background of every granted patent.

The due date is not on any certificate

Nothing in the grant papers says when your first statement is due. You have to work it out from the grant date. A portfolio of thirty patents granted in different years therefore has thirty different starting points.

The rule changed in 2024

Until early 2024 the statement was filed every year. It is now filed once for every block of three financial years. Many teams still carry the old yearly habit in their diaries, and some do not know that the new rule applies from 15 March 2024.

Both patentee and licensee have a duty

A licensee must file too. One party filing does not remove the duty of the other. In a portfolio with many licences, that means more names to track, not fewer.

02The rule in one minute

Form 27 is filed once in every three financial years, under Section 146(2) read with Rule 131(2) of the Patents Rules.

Form 27 is now due once per block of three financial years, by 30 September after the block ends. The grant year itself is never part of a block.

• Block start: the first day of the financial year after the year in which the patent was granted.
• Block length: three consecutive financial years.
• Due date: within six months of the block ending, which means 30 September.
• Next due dates: 30 September 2026 and 30 September 2027, depending on the grant year.
• What you report: whether the invention was worked in India during the block, the reasons if it was not, and whether licences are available. The revenue detail asked for under the old form is no longer the focus.

The IPO FAQ dated 26 August 2024 also clarifies the switch from yearly to three-yearly filing. It says, in particular, that Form 27 cannot be filed for a due date that had already expired before 15 March 2024.

03The 3-year block table

Use this table to find your first block and due date from the financial year of grant. Financial years run from 1 April to 31 March.

After the first block, the next block simply follows it. A patent whose first block ends in March 2026 has its second block running April 2026 to March 2029, with the next due date on 30 September 2029.

The first row needs care. Patents granted before FY 2022-23 are widely reported to fall into the FY 2023-24 to FY 2025-26 block, with the filing due on 30 September 2026. Check each such patent against the IPO FAQ before you rely on this row.

The grant year itself is never reported. A patent granted on 10 May 2023 is a FY 2023-24 grant, so its first block starts on 1 April 2024.

04How to track Form 27, step by step

Follow these steps once for the whole portfolio, then keep the calendar alive.

1. List every granted patent. Note the patent number, grant date, patentee, and every licensee, exclusive or non-exclusive.
2. Convert each grant date to a financial year. Grants from 1 April to 31 March belong to one year. A grant on 2 April 2024 is FY 2024-25.
3. Find the first block in the table above. Start from the next financial year and count three years.
4. Set the due date as 30 September after the block ends. Add the date to your calendar, with reminders at 90, 30 and 7 days.
5. Collect working facts early. Ask the business team and licensees whether the invention was worked in India in each year of the block, and keep the evidence.
6. File for the patentee and, separately, check each licensee. A licensee statement is the licensee’s own duty.
7. Record the filing and set the next block. The moment you file, add the next three-year block and its 30 September date.

For the other patent deadlines that sit beside this one, see our Indian patent deadline master calendar.

05Mistakes to avoid

Counting the grant year

The block starts the year after grant. Counting the grant year pulls every date one year early or leaves the wrong years in the statement.

Using the old yearly habit

Filing every year is no longer needed, but dropping the habit without a replacement calendar is the real danger. Replace it, do not just delete it.

Forgetting licensees

Keep a licensee column in your register. If a licensee is silent, follow up in writing.

Ignoring the cost of getting it wrong

The Patents Act provides a penalty for failing to furnish the statement and a separate penalty for furnishing false information, in Section 122. The amounts and the extension of time routes under Rules 131 and 138, with Form 4 and extension fees, are reported differently across secondary sources, so read the rule text and the current fee schedule before you plan around any figure.

If your next problem is lenders or counterparties checking patent and litigation exposure, see pre-sanction borrower litigation screening.

06Where Claw fits

Claw is an all-in-one legaltech platform for Indian advocates, law firms, and corporate legal teams, combining AI-based case search, an AI legal assistant (Legal GPT), case management, and compliance automation across all Indian courts and tribunals.

A working dispute, a revocation or a compulsory licensing request can turn a Form 27 gap into litigation, where you need to see how the point has been argued before. Claw lets you search and track cases, orders and hearings across 9,102 courts, benches and forums, with 30 crore+ judgments and results in under 5 seconds, so you can research patent judgments and follow a live matter by party or advocate name, with Supreme Court judgments from 1950 and High Court judgments from 1990.

Claw does not use customer documents to train AI models. Create a FREE Claw account to research patent decisions and track live matters by party or advocate name. To search the wider body of law, see case search across Indian courts.

07Sources and further reading

Check every date and rule against the primary source before you file:

• Indian Patent Office (IP India), rules, forms and the FAQ dated 26 August 2024: ipindia.gov.in
• Patents Act, 1970 (Section 146) and Patents Rules, 2003 (Rule 131): official text on ipindia.gov.in
• Claw: clawlaw.in

This guide is general information and not legal advice. Last verified October 2026.

08Frequently asked questions