InPASS vs Google Patents vs Espacenet vs PATENTSCOPE: Measured Indian-Patent Coverage
InPASS, Google Patents, Espacenet and PATENTSCOPE, compared on one question: how much of the Indian patent record does each one actually return? Last verified October 2026.
Benchmark Guide · Patent Prior Art Search
You are about to file a patent, or to oppose one, and you need to know if something Indian already exists. Most people search Google Patents first, because it is easy. Then they find out the Indian record in it is thinner than the record at the patent office. This guide compares the four free databases people actually use for Indian prior art search, explains how to measure coverage fairly, and says plainly where paid AI tools do better. Last verified October 2026.
- Official Indian record: InPASS from the Indian Patent Office is the reference, and it is free.
- Foreign prior art and families: Google Patents and Espacenet; PATENTSCOPE for PCT.
- Coverage claims: trust only a percentage that states N and a test date. This page gives the method and publishes no figure until the test is run.
- Hard-to-describe inventions: paid AI tools (PatSnap, Questel, IPRally) are stronger.
- Claw: not a prior-art database; it tracks Indian IP registry matters, deadlines and IP litigation in one place.
01Why Indian prior art is easy to miss
Prior art search means looking for anything already published that could affect whether your invention is new and not obvious. A search that misses one Indian document can mean a wasted filing fee, a weak patent, or a lost opposition. There are three reasons Indian prior art is easy to miss.
Data lives in many places
The official Indian record sits with the Indian Patent Office. Global tools such as Google Patents, Espacenet and PATENTSCOPE collect data from many offices, and each one gets its Indian data in its own way and on its own schedule. They are not copies of the Indian record.
Indian documents are often not searchable the same way
Older Indian records may be scanned images, and text fields can vary in quality between databases. A tool can list an Indian application but not search its full text. That difference does not show up unless you test for it.
Prior art is not only Indian
An Indian examiner, or an opponent, can rely on a document from any country. So the right search covers both the Indian record and the world. No single free tool is best at both.
A different job: searching court judgments
This guide is about finding prior art in patent databases. Reading patent litigation judgments is a separate research task. For checking that a citation will hold in court, see court-ready citation verification in India.
02What good prior art search looks like
Four things separate a strong search from a weak one.
- Indian completeness: of the Indian publications that exist, how many does the tool return? This is the number most blogs skip.
- Full-text depth: can you search the claims and description, or only the title and abstract?
- Legal status and family data: can you see if an application is pending, granted or lapsed, and find its foreign equivalents?
- Cost and workflow: is it free, and can you export, save and repeat the search?
A search tool is only as good as the share of the real record it can actually return. Always ask for N and the test date.
03The four databases for Indian patent search
These four are listed in a neutral order, not a ranking. Each has a different job. We describe what each is for and where it falls short for Indian prior art.
InPASS (IP India)
The official public search system of the Indian Patent Office.
Strengths
- It is the official source for Indian published applications and granted patents, so it is the reference point for Indian completeness.
- Free to use and open to the public without registration.
- Supports Boolean and wildcard operators, and shows application status.
Keep in mind
- Indian record only. It will not show you foreign prior art.
- The interface is basic, and it is weak for concept or similarity searching.
- Results export and repeat searches take manual effort.
Best for Checking the official Indian record and application status.
Google Patents
A fast, free, full-text search across many countries.
Strengths
- Easy interface, quick results, and good similar-document discovery.
- Covers many patent offices in one place, so foreign prior art is easy to reach.
- Free.
Keep in mind
- Indian coverage should be tested, not assumed. It may not match the official Indian record in completeness or timing.
- It does not replace the official source for Indian legal status.
Best for A quick first pass and foreign prior art.
Espacenet (EPO)
The European Patent Office database, strong on families and legal status.
Strengths
- Strong patent family and classification search across a very large worldwide collection.
- Useful legal status information through the EPO register data.
- Free.
Keep in mind
- Indian full text coverage can be limited compared with the Indian office. Test before you rely on it.
- Better for families and classes than for Indian detail.
Best for Finding foreign equivalents of an Indian application and searching by classification.
WIPO PATENTSCOPE
WIPO's database, strongest for international PCT applications.
Strengths
- The main place to search published PCT international applications.
- Multilingual search tools, which help with documents in other languages.
- Free.
Keep in mind
- Indian national phase documents are not its main strength. Do not treat it as the Indian record.
Best for Finding PCT applications that may later enter India.
04How to measure Indian coverage fairly
Many articles say one database is "more complete" than another without showing any test. We think that is not good enough. This is the method we recommend, and the one we use for any coverage figure.
- Fix the sample. Pick N Indian publications from the official source. Spread them across years, technology fields, and applicant types (individuals, companies, universities). State N in full.
- Search each one by number and by title. In every database, check if the document is found, and if its full text is searchable.
- Score two things separately. First, "found at all". Second, "found with searchable claims and description". The second number is usually lower.
- Write the test date. Databases update all the time. A figure without a date is not useful.
- Publish the list. Anyone should be able to repeat the test.
Using this method, InPASS is the reference, because it is the official Indian record. So the useful question is how close each global tool comes to it.
Coverage percentages: not yet published
We have not published a per-database coverage percentage in this version of the page. A percentage with no stated sample size and test date would mislead readers, so we show the method above instead. When the test is run, the page will list N, the test date, and each database result. Until then, run the five-step check yourself on a sample from your own field.
05Side-by-side comparison
| Database | Operated by | Indian record | Best use | Cost |
|---|---|---|---|---|
| InPASS | Indian Patent Office | Official source; the reference for Indian completeness | Indian status and official record | Free |
| Google Patents | Test before relying; not the official record | Fast first pass; foreign prior art | Free | |
| Espacenet | European Patent Office | Test before relying; strongest on families | Foreign equivalents; classification search | Free |
| PATENTSCOPE | WIPO | Not the main strength; strongest on PCT | PCT applications; multilingual search | Free |
No database wins every row. InPASS is the best for the Indian record. The global three are better for foreign art, families and PCT. A good search uses at least two.
06When to pay for AI prior art search
The free tools search by words, numbers and classes. If your invention is a concept that different people describe in different words, you may need paid tools built for similarity and structure search.
- PatSnap: an AI patent analytics and search platform, usually priced on quote.
- Questel: a long established IP search and analytics provider, usually priced on quote.
- IPRally: a patent search tool that uses graph-based AI search, usually priced on quote.
We do not give prices for these. They sell on demo or quote, and their pricing pages change. Ask each vendor for a written quote with GST shown, and test them on your own known documents first.
For high stakes work, such as a freedom to operate opinion or a pre-grant opposition, most firms combine a paid AI tool, the official Indian record, and a patent attorney's judgement. Under the Patents Act, 1970, prior publication is central to examination, pre-grant and post-grant opposition, and revocation, so a missed document has real cost.
07How to choose
If you need the Indian record, start with InPASS and treat it as the reference. If you need foreign prior art, add Google Patents and Espacenet, and use PATENTSCOPE for PCT filings. If the invention is hard to describe in keywords, consider a paid AI tool. If this is a one-off filing on a budget, the free four, used together, take you a long way.
Always save your search strings and dates. If you ever need to defend the search, that log is your proof.
Related reading: the legal side of Indian IP often needs registry watch as well. See Claw vs QuickCompany for trademark watch and Claw vs ProfIden. For patents that lapse and may be free to use, see the university patent lapse report.
08Where 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.
Claw is not a prior art database. It does not replace InPASS, Espacenet or a paid AI search tool, and for AI prior-art and structure search we point you to PatSnap, Questel and IPRally.
What Claw does is the work around the search. Its IPR Solutions tab tracks Indian Patent Office matters across trademarks, patents, designs and geographical indications. For patents, that means pending compliances such as annuity and response deadlines, and pending hearings. It also keeps related documents, tasks and activities in one place. For trademarks, it watches the Trade Marks Journal and flags conflicting marks by text, phonetic and visual matching.
On the court side, Claw tracks IP litigation across Indian courts that have a case website, including the High Court IP Divisions and their cause lists, orders and hearings. It also offers IP judgment research over 30 crore+ judgments, with LegalGPT. It covers 9,102 courts, benches and forums, with results in under 5 seconds, from the Supreme Court (1950) and High Courts (1990).
So the honest fit is this. Use the patent databases to find prior art. Use Claw to keep the registry matters, deadlines and court cases that follow in one all-India platform. For copyright, Claw is court-side only, because it does not yet track copyright registrations.
On pricing, IP features are part of the Premium plan (Rs 1,099 per month, or Rs 10,999 per year, excluding GST), or Enterprise on quote. There is no separate IP-only plan. Claw also has a free plan for individual advocates, and no free tier for teams. Claw does not use customer case documents to train AI models.
Where Claw is not the right pick: global multi-country docketing and annuities (Anaqua, Clarivate, Dennemeyer), very high volume specialist IP-firm docketing (Iolite, JSK), USPTO-first workflows (Alt Legal), mass marketplace takedowns (Red Points, Corsearch), and technology transfer office lifecycle tools (Wellspring, Inteum).
09Sources and further reading
Primary sources for the tools discussed. Always check these directly, because databases and fees change.
- Indian Patent Office (IP India): ipindia.gov.in
- InPASS public search: iprsearch.ipindia.gov.in/publicsearch
- Google Patents: patents.google.com
- Espacenet (EPO): worldwide.espacenet.com
- WIPO PATENTSCOPE: patentscope.wipo.int
- Claw: clawlaw.in
Last verified October 2026. This is not legal advice or a formal patentability opinion. Paid vendors are not priced here because they sell on quote.
10Frequently asked questions
What is the best patent prior art search tool for India?
There is no single best tool. InPASS is the official Indian record and the reference for Indian completeness. Google Patents and Espacenet are better for foreign prior art and patent families. Use at least two. For concept-level search, paid AI tools such as PatSnap, Questel and IPRally can do better.
Is InPASS free?
Yes. InPASS is the public search system of the Indian Patent Office and is free to use. Confirm the current access steps on the official site.
How complete is Google Patents for Indian patents?
We do not publish a percentage here, because a figure needs a stated sample size (N) and a test date, and we have not published that test yet. Check it yourself: take a sample of Indian publications from InPASS and search for each one in Google Patents.
Do I need a paid AI patent search tool?
Not always. For a simple check, the free databases used together are often enough. Paid AI tools help when the idea is hard to describe in keywords, or when the stakes are high, such as a freedom to operate review or an opposition.
Does Claw do patent prior art search?
No. Claw is not a prior-art database. It tracks Indian IP registry matters (trademarks, patents, designs, GI), including patent annuity and response deadlines and pending hearings, and tracks IP litigation across Indian courts. For AI prior art search, use PatSnap, Questel or IPRally.
How much does Claw cost for IP tracking?
IP tracking is included in the Premium plan at Rs 1,099 per month or Rs 10,999 per year, excluding GST, or in Enterprise on quote. There is no separate IP-only plan. Claw also has a free plan for individual advocates.