Scope and ownership of patents

Types of protectable inventions

Can a patent be obtained to cover any type of invention, including software, business methods and medical procedures?

A patent may be granted for computer software as either an invention of a product or an invention of a process, providing that it involves hardware control or process-using hardware. The mathematical algorithm itself is not patentable. Business methods themselves are not patentable; however, a patent may be granted for business methods that are combined with computer systems or other devices. Methods of medical treatment and methods of diagnosis for humans are not patentable, although Swiss-style claims are allowable. With respect to biotechnology, the mere discovery of micro-organisms that occur naturally or their components, such as a DNA sequence or protein, is not treated as a patentable invention that is industrially applicable, but if it is artificially isolated from its natural source or has mutated, and, further, if its utility is found and disclosed, it will be recognised as a patentable invention. Thus, genetically altered cells, plants and animals, and methods of producing them can be patented.

Patent ownership

Who owns the patent on an invention made by a company employee, an independent contractor, multiple inventors or a joint venture? How is patent ownership officially recorded and transferred?

Only a natural person can be the inventor. For an invention created by an employee, the right to obtain a patent may be assigned to an employer or even originally acquired in accordance with rules established by the employer, and the said employer may file the patent application as the applicant. The employer who acquired or is assigned the invention made by its employee shall compensate its employee in accordance with the rules of the employer; provided, however, that if said rules are found to be unreasonable in terms of the process for establishment, disclosure or application of the rules, the court may decide the compensation in light of the profits arising from the exclusive right to the invention and the employer’s own contribution to the invention (article 35 of the Patent Act). The right to file a patent application on an invention made by an independent contractor is held by the contractor, but is automatically transferred to other companies if the agreement between the parties provides for such a transfer. In the case of multiple inventors, the right to file a patent application is jointly held by all of them, and a patent application for such invention needs to be filed by all of them. The transfer of ownership of a registered patent becomes effective when such a transfer is recorded in the Japan patent office (JPO).

Patent office proceedings

Patenting timetable and costs

How long does it typically take, and how much does it typically cost, to obtain a patent?

To initiate the substantive examination, a request for examination must be filed with the Japan patent office (JPO) within three years from the filing date, including the international filing date, of the application. In 2019, a first office action (OA) was, on average, issued within 9-and-a-half months of a request for examination. A response to the OA has to be filed within three months of the mailing date of the OA (for foreign applicants, this is extendable up to six months by filing a petition prior to the initial due date). The subsequent OA (non-final rejection, final rejection, or notice of allowance) is usually issued within six to 12 months of the response. The final rejection may be appealed to the board of patent appeals (BPA) at the JPO, which usually takes around two years before reaching conclusion.

The official filing fee is ¥14,000, a fee for request for examination is ¥138,000 plus ¥4,000 multiplied by the ‘actual’ number of claims and the issue fee (including first to third annuities) is ¥2,100 plus ¥200 for each ‘actual’ claim.

On top of the above fees paid to the government, a patent applicant must pay fees to attorneys, if he or she hires them. It typically costs some thousands of US dollars per application, which varies greatly depending on the contents of applications and the attorneys. There is no standard for attorney fees for patent prosecution.

Expedited patent prosecution

Are there any procedures to expedite patent prosecution?

Accelerated examination

A patent applicant may request an accelerated examination under certain circumstances, such as if an applicant has filed a corresponding application with a foreign patent office, is undertaking marketing in Japan or is a university or small entity. In each of these cases, the fact must be established in writing. No official fee is required. The applicant may be asked to submit materials to help the examination, for example, cited references in a corresponding foreign application and brief comments thereon.


Patent Prosecution Highway

The Patent Prosecution Highway (PPH) programme is available for a Japanese patent application for which the first application was filed in Argentina, Austria, Australia, Brazil, Canada, Chile, China, Colombia, the Czech Republic, Denmark, Egypt, the European Patent Office, Estonia, Finland, Germany, Hungary, Iceland, Indonesia, Israel, Korea, Malaysia, Mexico, New Zealand, the Nordic Patent Institute, Norway, the Philippines, Peru, Poland, Portugal, Romania, Russia, Singapore, Spain, Sweden, Taiwan, Thailand, Turkey, the UK, the US, Vietnam and the Visegrad group. No official fee is required.


Patent Prosecution Highway-Mottainai

The enhanced PPH programme (PPH-Mottainai) is available for a patent application for which the first application was filed in Argentina, Austria, Australia, Brazil, Canada, Chile, China, Colombia, the Czech Republic, Denmark, the European Patent Office, Estonia, Finland, Germany, Hungary, Iceland, Israel, Korea, Malaysia, Mexico, New Zealand, the Philippines, Norway, Peru, Poland, Portugal, Romania, Russia, Singapore, Spain, Sweden, Taiwan, Turkey, the UK and the US. Prosecution history of an application filed with any of these patent offices may serve as the basis for PPH regardless of first filed or not. No official fee is required.

In all of the above cases, a first OA would be expected to be issued within one to four months of such a request (the average time in 2015 was 2.3 months).

Patent application contents

What must be disclosed or described about the invention in a patent application? Are there any particular guidelines that should be followed or pitfalls to avoid in deciding what to include in the application?

A patent specification must sufficiently describe ‘how to make’ and ‘how to use’ the claimed invention in such a manner that those skilled in the relevant art can easily carry it out. Also, the specification must describe the claimed invention in such a way as to reasonably convey to one skilled in the relevant art that the inventors, at the time of the application was filed, had possession of the claimed invention.

Regarding the inventions of which the effects are not predictable from their structures, for example, chemical compounds, working examples showing the effect of the invention must be disclosed in the specification as filed. Working examples should be commensurate with the scope of the claims.

Especially, with respect to patent applications directed to therapeutic uses (ie, pharmaceutical composition claims or Swiss-style claims), the JPO strictly requires that the ‘specification as filed’ discloses the results of the relevant in vitro or in vivo tests that demonstrate feasibility in the treatment. In this regard, the JPO will not accept any late submission after the filing of the application if the specification as filed does not disclose any test results and only describes prophetic examples.

Prior art disclosure obligations

Must an inventor disclose prior art to the patent office examiner?

Patent applicants are required to disclose any prior art references known to the applicants before the priority date. This requirement will be met if the applicant lists the prior art references in the specification. In the case of insufficient disclosure, however, the examiner may issue an OA and ask the applicant to submit additional prior art references. Failing to respond to the OA may result in a final rejection. However, once a patent is issued, the violation cannot be grounds for invalidity.

Pursuit of additional claims

May a patent applicant file one or more later applications to pursue additional claims to an invention disclosed in its earlier filed application? If so, what are the applicable requirements or limitations?

It is possible to file later applications before the earlier filed application is laid open to the public, namely, the issuance of patent application publication, which is usually 18 months after the priority date, provided that the applicant or the inventor has not disclosed the invention elsewhere.

That is, even though the Patent Act has a similar provision to the European Patent Convention, article 54 (3), the Japanese provision will not apply to the later applications filed by the same applicant or in the name of the same inventors as the earlier filed application. However, the applicant (or all the applicants in the case of joint applicants) of the later applications must be exactly the same entity as those of the earlier filed application at the time of filing the later applications, or the inventor (or all the inventors in the case of joint inventors) must be exactly the same as those of the earlier filed application.

Additionally, within one year from the filing date of the earlier application, domestic priority in later applications can be claimed. One or more divisional applications can be filed within certain periods, namely, before the issuance of a first OA, the due period for responding to OA, within 30 days from receiving notice of allowance from the examination division or the due period for filing notice of appeal from final rejection by examination division.

Patent office appeals

Is it possible to appeal an adverse decision by the patent office in a court of law?

Final rejection by the examination division may be appealed before the BPA at the JPO. Where the BPA renders a decision to reject an application, the applicant can appeal the decision to the IP High Court, which is the relevant court of law. Regarding the JPO’s decision for an invalidity action or correction of claims, which are made after the issuance of the patent, the party who received an adverse decision from the JPO can appeal to the IP High Court.

Oppositions or protests to patents

Does the patent office provide any mechanism for opposing the grant of a patent?

Any party may file an opposition within six months after issuance of an Official Gazette for the patent. The grounds for opposition include:

  • lack of novelty or inventive step;
  • interference with another patent application having earlier priority date;
  • violation of claim clarity, enablement or written description requirements; and
  • violation of conditions for an amendment made during prosecution, etc.


The grounds for opposition are the same as the grounds for invalidation trial, with the exception that false inventorship is not a ground for opposition. The proceedings for multiple oppositions to the same patent are usually consolidated. There are no oral hearings in opposition proceedings, and all arguments and evidence need to be filed in writing.

A third party, who has interest in validity of the patent, may file a nullity action (trial for invalidation) at any time. Usually, a single oral hearing will be held. The patentee may have a chance to amend the claims during the trial procedure.

Priority of invention

Does the patent office provide any mechanism for resolving priority disputes between different applicants for the same invention? What factors determine who has priority?

Japan adopts the first-to-file system. A patent application with an earlier filing date defeats a later application concerning the same invention. The priority among applications with the same filing date is decided by an agreement among the applicants through mutual consultation. If no agreement is reached, none of the applicants will obtain a patent for the invention.

Modification and re-examination of patents

Does the patent office provide procedures for modifying, re-examining or revoking a patent? May a court amend the patent claims during a lawsuit?

After issuance of a patent, the patentee can amend the claims by filing a trial for correction before the BPA at the JPO. The trial for correction can be filed at any time unless a trial for invalidation is pending before the BPA at the JPO or an appeal therefrom is pending before the IP High Court. While a trial for invalidation is pending, however, the patentee can make a request for correction within a very limited period during the procedure of trial for invalidation as above.

Patent duration

How is the duration of patent protection determined?

A patent expires 20 years after the filing date of the patent application. For pharmaceutical and agrochemical patents, a patent term extension is available for up to five years upon request by the patentee if the patentee or a licensee thereof receives marketing approval for the patented drug or pesticide from the Japanese authority.

Law stated date

Correct on

Give the date on which the information above is accurate.

19 February 2021.