• Dr. Mohan Dewan

Provisions for third party observations are well established in certain jurisdictions like the UK Intellectual Property Office and the European Patent Office (EPO). From September 2012, the America Invents Act also introduced provisions for third-party submissions on US patent applications. These provisions are based on similar concepts as the pre-grant oppositions in several countries like India, New Zealand, Australia, Peru etc., of assisting the patent office in determining the patentability of the invention before the grant of the patent and to increase the validity and quality of the granted patents. Though post-grant opposition systems do exist in most countries, they are not only cumbersome but also very expensive.

PCT Third Party Observations

In view of this, the World Intellectual Property Organization (WIPO), from July 2012, introduced a system for incorporating third party observations, realizing that the International Searching Authorities (ISA), despite conducting a thorough prior art search might unintentionally miss out on certain publications which may be relevant. The reason being that a system for conducting a “perfect prior art search” does not exist. The sheer volumes of publications in different languages make it virtually impossible for the ISA to track down each and every relevant prior art; however, persons involved in that particular field may be aware of most of the relevant prior art that could challenge the patentability based on lack of novelty and/or inventive step. Third party observations (or reporting relevant prior art) assist the ISA, the International Preliminary Examining Authorities (IPEA) and the patent offices in identifying such prior art in the international phase, before the grant of the patent by any country.

Up till now there was no mechanism for third parties to challenge PCT applications before they entered the national phase of each country. This new system provides an opportunity to persons skilled in the art to make observations on pending PCT applications, during the international phase, if they believe that the claimed invention either lacks novelty or inventive step. It is a simple, centralized and an informal way of publicly questioning the validity of a patent. The objective is somewhat similar to the pre-grant opposition system prevalent in India from January 2005 under sec. 25(1) of the Indian Patents Act.

A Comparison between PCT Third Party Observations and Pre-Grant Oppositions

A comparison between PCT third party observations and pre-grant oppositions u/s 25(1) of the India Patents Act reflects the following similarities and differences:

  • By whom:

Both may be submitted by any person and not necessarily by an interested person. However, in the case of third party observations, the person filing the observations may elect to remain anonymous, though their details would have to be entered via a WIPO account.

  • Manner of filing:

PCT third party observations, along with the cited prior art documents, have to be submitted online through ePCT public services, using a standard WIPO user account; whereas pre-grant oppositions can be submitted either online through the e-filing route or physically by filing hard copies at the appropriate Indian patent office. The Indian patent rules do not specify any particular format for submission, however, among the proposed changes to the Indian patent rules, a specific form for pre-grant opposition, “Form 7A”, is being proposed.

  • Grounds:

Both are restricted to certain specific grounds - third party observations are limited to comments on novelty and inventive steps whereas pre-grant oppositions are limited to the grounds enumerated u/s 25(1), including novelty and inventive step.

  • Rule of Ten:

One major difference is that in third party observations under the PCT, each person making the observation is restricted to making only one observation on one PCT application, with a maximum of 10 observations being submitted by 10 persons for any one PCT application. Each observation can comprise a list of a maximum of 10 citations (referring to accompanying prior published documents) together with an indication of how each one is relevant to the novelty or inventive step; while in pre-grant oppositions there is no such restriction on the number of grounds, number of citations/evidence or the number of persons filing oppositions.

  • Time period:

Both have limitations as to the time of submission - third party observations can be submitted any time from the international publication date to within 28 months of the priority date of the PCT application; whereas pre-grant oppositions can be submitted any time after publication but before the grant of the patent. However, since the grant of a patent may be delayed due to various reasons, the time for submitting pre-grant oppositions also gets extended. Such extension is not possible in the case of third party observations.

  • Cost:

In both the cases no fee is incurred.

  • Review:

Both are reviewed to check for their validity before being published or considered by the examiner. However, in the case of pre-grant oppositions, the review is undertaken only after an application for examination has been filed; while for third party observations there is no such condition.

  • Publication:

If the observations are found to be valid on review, WIPO makes them publicly available on PATENTSCOPE, however, the accompanying prior art documents are not made public. These are available only to the applicant, competent international authorities and designated offices.

  • Consideration by examiner:

In the case of third party observations, the examiner at the national patent office is free to ignore the observations, even if WIPO found it to be valid and published it; whereas in the case of pre-grant oppositions, if the opposition is found to be valid, it cannot be ignored, and statutory procedure has to be followed to evaluate whether a patent can be granted or not.

  • Response by applicant:

Under both the systems there is a limited time for filing a response by the applicant. For third party observations, a response may be filed any time within 30 months of the priority date of the PCT application, but it is not mandatory to file a reply. For pre-grant oppositions, the response is mandatory and must be filed within 3 months of receiving the opposition notice by the applicant.

  • Participation by third party/opponent:

Persons who file third party observations cannot as a matter of right interfere, participate or influence further processing of the application, and therefore no delays are caused because of such observations; whereas, a person who files a pre-grant opposition has a right to be heard, if allowed by the controller, and mandates certain procedural formalities if the pre-grant opposition is found to be valid by the examiner. This in many cases leads to unnecessary delays in the grant of patents, especially in the case of pharmaceutical patents. At the same time, pre-grant opposition hearings burden the patent office working.


The main advantage of the PCT third party observations over the Indian pre-grant opposition system is that it is a centralized system. Each observation, challenging the patentability, will be effective in all the states, without any extra cost or other associated formalities. It would be applicable to even those states which do not have a similar system in place for challenging the validity of a patent. Third parties do not have to wait for the application to enter the national phase in order to file a pre/post-grant opposition in various countries. Although the national patent offices are not bound to follow these observations, they become a part of the official file and are accessible to the public to challenge that patent later on (or even similar patents) on that basis. The observations and the relevant prior art filed may make it more difficult for a competitor to obtain a patent in various countries. Also, it does not cause any delays in the grant of patents in the national phase.

The major disadvantage of the PCT third party observations over the pre-grant opposition system is that the national patent offices, ultimately responsible for granting the patent, are not bound by such observations and are free to ignore them altogether. The observer has no say in the matter. Thus, the main objective of improving the quality of patents or of preventing frivolous and unworthy patents from being granted gets defeated if the national patent offices choose to ignore the comments. In such cases, the third party who filed the observation has to ultimately wait for the national phase prosecution in order to take appropriate further action to challenge the invention and present its arguments.


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