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Is it advantageous to file a TPO?


Yunjin Choi of Shiga International Patent Office evaluates the advantages and disadvantages of filing a third party observation before and after the establishment of a patent right


The system of third party observations (TPOs) allows two actions. Firstly, as a result of this system, information can be provided to the patent office to stop an invention from being patented because a patent application has already been submitted by another party for this invention. Secondly the system means that others can inform the patent office of the possibility that a reason for revocation or invalidation exists in relation to a patented invention. In recent years, the number of TPO cases has exceeded 5,000 annually, and since such TPOs can be submitted almost without restriction and the system offers an opportunity to sufficiently explain the relationship between the content of a publication and an invention in question, it has become an extremely convenient tool.

Overview of the TPO

(1) A TPO is conducted by submitting a document called "Submission of Publication, etc." to the patent office.

As the name implies, this document is for submitting a "publication, etc." as information. When submitting a "Submission of Publication, etc.", unlike during an invalidation trial, it is not necessary to pay any stamp fee to the patent office, i.e. there are no patent office fees for submission of a TPO.

(2) A TPO can be provided with regard to a patent application that has been published or a patent (patent right). One important feature of the TPO system is that information can be provided even after an invention has been patented, i.e. after a patent right has been established.

(3) The only information which can be provided is a document. The submission of information that does not correspond to a document, such as a video tape or a CD-ROM, is not permitted.

(4) Anyone can provide information through the system.

The "Submission of Publication, etc." includes a section for writing the submitter's name, but it can be submitted without any name or address recorded therein. In other words, the Submission of Publication, etc. can be submitted anonymously without any indication of who made the submission, or as a dummy submission. However, it should be noted that the patent applicant or the patent right holder is notified when information has been provided.

(5) In the "Submission of Publication, etc.", a list of documents being submitted must be included and the reasons for submission must be explained. The following are possible reasons for such TPOs:

  • Article 17bis, Paragraph 3 (Addition of New Matter);

  • Article 29, Paragraph 1, Main Paragraph (Non-Statutory Invention or Lack of Industrial Applicability);

  • Article 29, Paragraph 1 (Lack of Novelty);

  • Article 29, Paragraph 2 (Lack of Inventive Step);

  • Article 29bis (Lack of Novelty Due to Secret Prior Art);

  • Article 39, Paragraphs 1 to 4 (Previous Application);

  • Article 36, Paragraph 4, Number 1 (Violation of Description Requirements of Specification);

  • Article 36, Paragraph 4, Number 2 (Violation of Requirement for Disclosure of Prior Art Document Information);

  • Article 36, Paragraph 6, Numbers 1 to 3 (Violation of Description Requirements of Claims);

  • Article 36bis, Paragraph 2 (Addition of New Matter to Original Text).

A TPO is not permitted for any other reason, such as a violation of the unity of invention requirement, a usurped application, a violation of the joint application requirements etc.

If one believes that a claimed invention lacks novelty or inventive step in light of the prior art, such a person can submit a Submission of Publication, etc. and argue that the claimed invention is not patentable. The Submission of Publication, etc. must include the publication which denies the novelty or inventive step as well as the reason(s) for submission. The submission can be made not only by mail addressed to the commissioner of the patent office, but also via an electronic patent application terminal. Documents which already exist at the patent office, such as a published patent or a published patent application, do not need to be attached to the Submission of Publication, etc.

(6) The examiner may take such submitted publications into account when examining a patent application. However, it is at the examiner's discretion whether to consider such submitted materials. Therefore, no complaints can be made even if the examiner decides not to utilise the submitted publications, and even if a party provides information, such a party cannot request an interview with the examiner to explain the information because the party is not involved in the examination but is rather treated as merely a provider of information. However, in practice, more than 70% of submissions are used in a Notice of Reasons for Rejection.

(7) A TPO which has been submitted can be viewed, so patent applicants, patent right holders, as well as third parties may view the content of such a submission.

(8) If requested in the Submission of TPO, etc. an information provider may receive notice (feedback) from the patent office regarding whether the provided information was utilised during the examination. In the case of an anonymous submission, it is not possible to request such feedback, and thus an anonymous submitter must simply watch the examination proceedings on his or her own.

Below, we will discuss the advantages and disadvantages of the TPO system, both before and after a patent right has been established.

TPO before establishment of patent right


(1) Collective attack/prevention of patent right establishment

In an opposition or invalidation trial after a patent right has been established, the patent right holder can fight over each individual claim. However, before a patent right has been established, judgments are made regarding the patent application as a whole, and thus a patent will not be granted if a reason for rejection exists in even a single claim, and if the patentability is rejected for the first claim, which has the broadest scope, then the entire patent application will be rejected. Therefore, a collective attack on an entire patent application can be made during the application stage, and it is to be expected that after such an attack, the patent applicant may be forced to add limitations, which would be favourable to third parties, in order to satisfy the patent requirements for the entire application. In this way, the TPO system allows one party to prevent the establishment of a patent right detailed in another party's patent application, or at least reduce the scope of the granted patent right even if such an application is eventually granted.

(2) Earlier conclusion

When information has been provided, the possibility that such information will be used by the examiner is statistically high, so if one possesses information, submitting it can result in an early conclusion based on the submitted evidence during the examination stage, and this is advantageous in terms of establishing business policy.

(3) Anonymity

Oppositions, invalidation trials etc. cannot be requested anonymously. In contrast, TPO submissions can be made anonymously, and thus it is difficult for a patent applicant to discover who is interested in their application. In many cases, companies tend to avoid revealing themselves as concerned parties except in unavoidable situations, and thus the anonymity of the TPO system is an advantage.

(4) Low cost/low effort

The advantages are considerable in terms of the costs and effort required. Filing a TPO does not require a stamp fee, the examiner will probably act on such information, a submitter need only indicate the important passages so that the information in a TPO can be easily used by the examiner in the reasons for rejection and it is relatively cheap to request assistance from a patent law firm for filing a TPO.

(5) Puts pressure on examiner

Filing a TPO enables a third party to notify the examiner that they will be harmed if the patent application in question is granted. As a result, a TPO can be expected to put some pressure on the examiner when the presence or absence of inventive step is difficult to determine.


(1) Presence is revealed

When a TPO has been submitted, this signals to a patent applicant that there is a third party who may be harmed if the patent application is granted because patent applicants are notified that a TPO has been provided. As a result, filing a TPO may end up igniting the patent applicant's earnestness in seeking a patent grant.

In particular, for cases in the application stage, it is usually preferable to provide a TPO after a request for examination has actually been filed. Since the patent office will inform the patent applicant that a TPO has been provided, receiving notice that a TPO has been provided may spur a patent applicant to request examination of an application for which they previously had no intention of filing an examination request.

Furthermore, patent applicants attempt to investigate the products of other competing companies on the basis of the content of their own patent applications, and as a result of such investigations, they may attempt to cover a competing company's products in their own patent applications when responding to rejections.

(2) Easy to dodge

During the examination stage, there are many measures (including multiple instances of each measure) that can be taken by a patent applicant, such as amendments, divisional applications, requests for appeal against a decision of rejection, interviews etc. Thus, in comparison with taking action after a patent has been granted, the patent applicant may have a greater chance of dodging any attacks from a TPO. If a competing product exists, the chances are higher that the patent applicant will be able to react to a TPO by using various measures.

(3) Leads to stronger patents

If the patent applicant manages to dodge any attacks and receives a patent grant, the patent is likely to be stronger (harder to defeat), and this may lead to greater difficulties after the patent right has been established. In particular, as mentioned above in (2), since the degree of freedom with regard to measures such as amendments and divisional applications is greater during the examination stage, filing a TPO may help the patent applicant to form a better patent.

(4) Sufficient argument is difficult

Since a TPO provider is merely providing information, opportunities to express an opinion are limited. Of course, one may be able to substantially relay their opinion by means of another TPO, but this is not advantageous in that it is by no means equal to the measures which can be taken by a patent applicant.

TPO after establishment of patent right


While the effects of filing a TPO before a patent is granted are indeed significant in that a patent grant can be prevented in the first place, the following advantages also exist in filing a TPO after a patent has been granted.

(1) Careful exercise of rights

If a TPO, which has the potential to invalidate a patent, is submitted, it will certainly become more difficult for the patent right holder to exercise the right. Thus, unnecessary conflict can be avoided. Conversely, if one were to receive a warning regarding patent infringement from a patent right holder, it is helpful to check whether any TPO has been provided, because this might lead to the discovery of a useful countermeasure.

(2) Evidence in invalidation trial

When someone requests an invalidation trial, if a TPO has already been provided, this TPO can be referenced during the trial. In some cases, it may be possible to request a trial using the submitted TPO as evidentiary material. Of course, if you have evidence which can invalidate a patent, it may be better to request an invalidation trial yourself rather than provide the TPO. However, invalidation trials have their own associated costs, and require more effort in that you may receive a counterargument from the patent right holder. Further, an invalidation trial cannot be requested anonymously, and this creates the risk of provoking an attack from the patent right holder. In cases where the information is somewhat valuable but not sufficient to file a request for invalidation trial yourself, you may want to consider using the TPO system.

(3) Stage in which a dispute may arise

If a patent right holder actually sends you an infringement warning, or does not send a warning but instead distributes information to their customers or users that you are involved in an infringing act, you can inform the patent right holder of the existence of invalidation reasons by a TPO, and this may stop any further warnings or escalation of the dispute.

In addition, in an infringement trial, if you mount a defence under Japanese Patent Law, Article 104tris without requesting an invalidation trial, it may be advantageous to submit a TPO serving as evidence for the defence to the patent office whenever necessary. The patent right holder may request a correction trial to the patent office, and if a correction trial is requested, no one other than the patent right holder may participate. Therefore, it is wise to provide, at the necessary moment, information in a TPO which can serve as grounds for invalidation (as well as any other useful information) during an infringement trial (while the provisions under Japanese Patent Law, Article 168, Numbers 3 and 4 do exist, they are not stronger than a TPO).

However, careful decisions are necessary when considering filing a TPO after a patent right has been established because, depending on the case, requesting an invalidation trial or utilising the patent opposition system may actually be more effective. The TPO system should be used effectively upon careful consideration of the above advantages and disadvantages of filing a TPO.

Yunjin CHOI



Ms Choi represents parties in court in IP infringement litigation. She specialises in near-field optics. She has experience in the research and development of polymer organic EL displays, and patent prosecution in the field of semiconductors, optical devices, magnetic devices, industrial machinery, and medical devices.

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