JPO Patent Search: Find Japanese Patents with J-PlatPat

For Japanese patent searching, the Japan Patent Office's search FAQ directs users to J-PlatPat. The service is operated by INPIT, the National Center for Industrial Property Information and Training, and includes patent, utility-model, design and trademark publication databases.

CNIPA.AI is an independent research and drafting service, not JPO or INPIT. This guide explains where to begin and what to verify; it does not replace the official database or its current help pages.

Choose number search or keyword search

When you already have an identifier, the JPO FAQ describes Patent/Utility Model Number Search/OPD. Select the number type that matches your source and enter the identifier in the corresponding field. An application number, a publication identifier and a grant-related identifier should not be treated as interchangeable.

When you have only a technical topic, use Patent/Utility Model Search, choose the search item and enter the relevant keywords. The official FAQ directs users to each database's Help list for details. The interface may evolve, so use the current labels and help rather than assuming a screenshot from an old tutorial is unchanged.

Can you read Japanese patents in English?

The JPO FAQ states that machine-translated publications are available through J-PlatPat. It also notes that the covered years differ by publication type. Availability of translated material does not establish that every publication, field or procedural document has an English version.

Use translation to understand candidates, then return to the original where the wording affects your conclusion. Keep the original document identifier and the relevant claim, paragraph or figure reference with any translated excerpt.

Develop a search beyond one English phrase

Separate the technical object, operation and distinguishing features. Read useful candidate documents to identify the terminology they use, including Japanese terms where appropriate, and consult the service's classification functions and help.

For example, searching for a temperature-monitoring device involves more than the phrase “temperature monitor”: the relevant mechanism may concern measurement intervals, thresholds or notification conditions. This is a conceptual example, not a completed patent search. Do not claim the invention is new merely because one phrase returns nothing.

Check status separately from technical similarity

The JPO FAQ explains that legal-status information is available through J-PlatPat and describes opening the relevant document details. Confirm that you are looking at the right application or publication before interpreting a status or procedural event.

Record the date and the source of the status check. A similar title or translated abstract does not establish that a right is active, that claims match another family member, or that a proposed product may be used without further analysis.

Continue your research or prepare documents

Open Japan-scope search in CNIPA.AI to explore the records available to our product. Coverage depends on connected sources and is not identical to J-PlatPat. Use the official database to verify important source information and retain unsearched areas in the research log.

If your next task is preparing an application, move to the Japanese drafting and document guide. Finding prior art, drafting documents and submitting an application are separate activities.

Is J-PlatPat the same organization as JPO?

No. JPO is the patent office; J-PlatPat is an information service operated by INPIT and linked from the JPO website.

Can the search tell me in advance that a patent will be granted?

No. The JPO FAQ explains that the office does not provide a pre-filing guarantee of patentability. Search results are evidence for further evaluation, not a grant decision.

Does a zero-result search mean no relevant Japanese document exists?

No. Revisit identifiers, terminology, fields, dates and publication coverage. Record the conditions used and the information you could not check.

Official reference

The JPO English search FAQ was read on September 26, 2026. For a wider choice of official sources, see the global patent-office guide.