Section 137 of the Patents Act, 1970
Multiple priorities
Explains how claims in one Indian convention application take their dates when several earlier foreign applications are relied on.
Official legal text
The verbatim statutory text of this provision is reproduced from the official source and checked by our legal reviewer before it is published here. Until that check is complete for this page, read the exact wording directly from the official source linked below — it is the only version that governs.
Read this as a plain-language summary. If it and the official text, or a relevant Gazette notification, say different things, the official text and the notification are what count.
What this section says, in plain language
Inventions rarely arrive fully formed. A company may file abroad in January for a core mechanism, in May for an improved control method, and in September for a manufacturing variant, and then want a single Indian application covering all of it. Section 137 makes that possible and explains the consequences. Where a single convention application in India is based on two or more basic applications, each claim takes the date of the earliest basic application that discloses the subject matter of that claim.
The result is an application in which different claims carry different priority dates. That is normal and perfectly proper. Claim 1 may sit on the January date, a dependent claim on the May date, and another independent claim on the September date. What a claim cannot do is take an earlier date than the filing that actually disclosed it, and matter that appears in none of the basic applications takes the Indian filing date.
This has direct consequences for how prior art is assessed. An examiner or an opponent will not test the whole document against a single date. Each claim is measured against what was publicly available before its own priority date. A publication from June may destroy a claim entitled only to the September date while leaving the January claims untouched. Careful applicants keep a table mapping every claim to the basic application that supports it, and update it whenever claims are amended.
The section works with section 135, which permits cognate inventions filed abroad to be combined into one Indian convention application, and with section 11, which performs the same dating exercise for claims in domestic cases. Section 136 supplies the formal requirement to identify each basic application, which is what makes multiple priority workable in the first place.
The drafting lesson is simple. Combining filings saves cost and produces a tidier portfolio, but it demands discipline. If the specification blurs the boundaries between what came from which filing, the applicant will struggle to defend the earlier dates when they are challenged, and the benefit of the earliest filing may quietly be lost.
Why this section matters
Applicants consolidating several foreign filings into one Indian application, and anyone attacking or defending a priority claim.
At drafting and filing of the Indian convention application, and again whenever claims are amended during examination or opposition.
A claim by claim dating rule that lets a single application carry more than one priority date.
Claims may be assumed to enjoy the earliest date and then fall to intervening prior art that the applicant never expected to face.
How it works in practice
Three foreign filings, one Indian application, three dates
Aravali Instruments, a fictional company with a research unit abroad, files in a convention country in February for a soil moisture probe, in June for a wireless calibration routine used with the probe, and in October for a low cost housing that suits humid conditions. In January of the following year it files a single Indian convention application covering all three, identifying each basic application with its country and date. The Indian examiner cites a Brazilian article published in August describing a similar calibration routine. Because the calibration claims are entitled to the June date, the August article does not count against them. A separate claim to the housing, disclosed only in the October filing, faces a September conference paper and is narrowed to a feature that the earlier probe disclosure supports. The company's claim to priority table, prepared at drafting stage, lets its agent answer the objections in one reply rather than three, and it survives the examination with most of its scope intact.
Simplified illustration only. Actual legal outcomes depend on the facts.
Key points to remember
- One Indian convention application may rest on several basic applications filed in convention countries.
- Each claim takes the date of the earliest basic application that disclosed its subject matter.
- Different claims in the same application can therefore have different priority dates.
- Matter not disclosed in any basic application takes the Indian filing date.
- Prior art is assessed claim by claim against each claim's own priority date.
- A claim to priority mapping table is the practical tool that keeps this manageable.
Common mistakes and misunderstandings
- Assuming the earliest priority date covers the whole specification. Support has to exist in the basic application relied on.
- Amending claims during examination without rechecking which basic application supports the amended wording.
- Merging several filings into one Indian application without recording which disclosure came from which filing.
- Believing that adding a feature during drafting is harmless. Anything new is judged from the Indian filing date.
Connected provisions
- ActSection 135Convention applications
- ActSection 136Special provisions relating to convention applications
- ActSection 138Supplementary provisions as to convention applications
- ActSection 11Priority dates of claims of a complete specification
- ActSection 13Search for anticipation by previous publication and by prior claim
A section of the Act states what the law requires. The detail of complying with it, including forms, periods and office procedure, sits in the Patents Rules, 2003. The Rules are a separate instrument and change far more often, so they are shown alongside rather than folded into the section.
Forms, deadlines and fees
The Second Schedule to the Patents Rules contains the prescribed forms. A form that has been amended will not match an older saved copy, so take a fresh download from the official site before you fill anything in.
- Where several basic applications are relied on, the Indian application must still be filed within twelve months of the earliest of them.
Open the deadline calculator — and have every date confirmed against the current Rules before you rely on it.
Any official fee connected with this provision is fixed by the First Schedule to the Patents Rules, not by the provision itself. The amount depends on who the applicant is and on whether the filing is made online or on paper, so no figures are reproduced here. How Indian patent fees work.
Related judgments
No judgment summaries appear here yet. Our process requires a legal review of each case note before publication, covering the citation, the court and the point actually decided. Until a note for this provision has passed that check, the section stays empty rather than carrying unverified material. How case notes are prepared.
Questions people ask about Section 137
Can one Indian patent application claim priority from several foreign applications?
Yes. Where a person has filed in one or more convention countries for inventions that belong together, a single Indian convention application can be based on all of them, provided it is filed within twelve months of the earliest. Each basic application must be identified with its country and date. The effect is described in section 137: each claim takes the date of the earliest basic application that actually disclosed what that claim covers.
Can different claims in the same patent have different priority dates?
Yes, and this is common in multi priority cases. A claim entitled to an early basic application keeps that date, while a claim whose subject matter first appeared in a later filing gets the later date. Claims resting on material found in no basic application take the Indian filing date. Prior art is then assessed against each claim's own date, so a publication may knock out one claim of a patent while leaving others perfectly valid.
How do I prove which basic application supports a claim?
By pointing to the disclosure. The test is whether the earlier application disclosed the subject matter of that claim, so you compare the claim wording against the description, drawings and claims of the basic application. This is why a claim to priority table prepared at drafting stage is worth the effort. In examination and in opposition, the applicant who can show the supporting passage in one page usually keeps the earlier date; the one who cannot usually loses it.
What happens to features added only in the Indian specification?
They take the Indian filing date. That is not fatal, but it changes the prior art landscape for the claims that depend on those features, because anything published between the foreign filing and the Indian filing becomes citable against them. Where the added feature is commercially important, consider whether it deserves its own application rather than being buried in a document whose other claims enjoy an earlier date.
Combining several foreign filings into one Indian application?
MYCrave Consultancy builds the claim to priority mapping that keeps each of your earlier dates defensible.
You will be speaking with MYCrave Consultancy & Services, the firm that operates this platform. General questions are answered free; matter‑specific work is quoted before anything is done.