Japanese Patent FAQs

Opposition Procedures

Update 2020.8.17

Q.Who may file an opposition to grant of patent? When may the opposition be filed?

Any person may file an opposition to grant of patent within six months from the publication date of the patent gazette for the granted patent.

Q.Can the patentee identify the person who filed the opposition (i.e., the opponent)?

The copy of the written opposition should stipulate the name of the opponent. However, since an individual is often used as a straw person to hide the true opponent, in most cases, it would be difficult for us to identify the true opponent.

Q.Must the patentee file a response to the opposition written by the opponent?

No. The patentee does not have to file a response to the opposition itself. Instead, the patentee should file a response to the JPO’s opinion in cases where the JPO examines the opposition and decides that the patent should be canceled.

Q.Is an oral hearing required for opposition procedures?

No. The examination is based on filed paper documents and no oral hearing will be required.

Q.When can the patentee respond to the opposition if the JPO decides that the patent should be canceled?

The patentee will have an opportunity to file a response, that is, arguments and amendments (if any), against the JPO’s opinion after the JPO issues a Notice of Grounds for Cancellation. There are two chances to file the response to the opposition, because the JPO issues the Notice of Grounds for Cancellation two times before the JPO finally cancels the patent. You may also consult the flow chart from the following link.
https://www.ondatechno.com/en/procedures-in-japan/flowchart-for-opposition-procedure/

Q.Can the patentee respond to the opposition when the JPO decides that the patent should be maintained?

No. If the JPO decides that the patent will be maintained, the JPO will issue a Decision on Opposition to maintain the patent. In that case, there will be no necessity or opportunity to make a statement on the JPO’s decision.

Q.Can the patentee contest the JPO’s decision when the JPO decides that the patent should be canceled?

Yes. The patentee can contest the JPO’s decision by filing a petition at the Intellectual Property High Court.

Q.Can the opponent contest the JPO’s decision when the JPO decides that the patent should be maintained?

No. The opponent cannot contest the JPO’s decision. Instead, if the opponent is an interested party, the interested party can file a request for an invalidation procedure with the JPO. The invalidation procedure can be requested based on the same grounds as those for the opposition procedure.

Q.Can the opponent also file arguments during the opposition procedure?

Yes, in some circumstances. If the patentee files eligible amendments to the opposed claims in a response to the Notice of Grounds for Cancellation, the opponent will have an opportunity to file arguments except for under special circumstances (e.g., when the amendments are denied, when the amendments are minor, and so on). In contrast, if the patentee only files arguments in the response, or if the special circumstances apply, there are no opportunities to file arguments.

Q.What are downsides when a foreign third party (i.e., a resident outside Japan) uses a Japanese individual as a straw person to file an opposition without revealing their real identity?

The downside of using a Japanese individual as the opponent is that a Japanese opponent can obtain only a 30-day period for responding to arguments while a foreign opponent can obtain a slightly longer period of 50 days. Although a foreign individual can be also used as a straw person to obtain the longer period of 50 days, in this case, it is necessary that a Japanese patent attorney represents the foreign individual.

Q.What are the differences between opposition procedure and invalidation procedure?

This table shows the differences:

	Opposition procedure	Invalidation procedure
Purpose of Law	To provide opportunity to confirm validity of patent early	To solve conflicts between the parties
Requestor	Any party	Interested parties only
Examination method	Written submissions only	Written submission, however, an oral hearing is also possible
Period	Within six months of the issue date of the patent publication	Any time after issuance of a patent (even after expiration of the patent term).
Official fee (Ceiling)	16,500 + 2,400 x Number of claims	49,500 + 5,500 x Number of claims
Reasons	Novelty, Inventive Step, Written Description Requirement	Novelty, Inventive Step, Written Description Requirement, Problems of the Patentee, Rise of Grounds for Invalidation after issuance.
Preliminary notice before decision	When the requestor requests issuance (JPO sends a notice of Grounds for Cancellation.) Notice of reasons for revocation before decision to revoke is made (advance notice of decision)	JPO sends a preliminary notice before decision.
Participation of Requestor	The requestor can file an argument if a correction to claims is filed by the patentee.	The requestor participates in the procedures absolutely.
Interview	Requestor: Not possible Patentee: Possible	Not Possible
Withdrawal	Until notice of grounds for cancellation is issued.	Until completion of Invalidation procedures.
Legal effect of decision of cancellation of patent	Treated as if the patent had never issued	Treated as if the patent had never issued
Filing Lawsuit with the Intellectual High Court	The patentee who received a decision of cancellation can file.	Both the requestor and the patentee can file.

FAQs