In Brazil, the PTO’s decision to grant a patent can be challenged through two pathways. Within six months from grant, any interested third party may file—or the BRPTO may start ex officio—an administrative post-grant opposition. Alternatively, any interested third party or the BRPTO may file an invalidity lawsuit before the Federal Courts.

Upon the filing of a post-grant opposition, the patent office will summon the patent owner, who has a statutory 60-day term to present a written reply. The patent owner can also submit evidence to the BRPTO, such as technical opinions, additional data, decisions from other jurisdictions etc. If more than one post-grant opposition is filed for a same patent, the BRPTO will unify the proceedings by issuing only one summon order for the patent owner. For that reason, the BRPTO will only issue a summon order once the 6-month term has elapsed, even if an opposition has been filed months before this deadline.

The patent remains valid and in effect during the post-grant opposition proceeding. The BRPTO does not have the authority to stay the patent while the proceeding is pending. For that reason, it is common for interested third parties to file a post-grant opposition request only when there is no urgency. Otherwise, an invalidity lawsuit is a better option.

After the patent owner presents their reply to the post-grant opposition request(s), the BRPTO will assign a new body of examiners for the case. The parties can request a meeting with the BRPTO’s technical body to discuss the arguments and evidence submitted. This meeting is usually held ex-parte.

The BRPTO then publishes an intermediate opinion suggesting that the patent be upheld as granted, upheld with amendments, partially invalidated, or totally invalidated. The parties have a 60-day term, counted from the publication of this opinion, to submit petitions in response. However, the BRPTO does not accept the submission of new evidence by either side, nor do they grant meeting requests. If the intermediate opinion contains recommendations of amendments, the patent owner can choose to comply with them and/or rebut the BRPTO’s arguments.

The BRPTO, upon analyzing the merits of the post-grant opposition, is not bound by the arguments contained in the initial request. It is not unusual for the patent office to consider other patentability requirements that had not been cited initially. For instance, there have been cases in which the BRPTO issue an intermediate opinion grounded on addition of matter or lack of clarity and precision of the claims even though such aspects had not been brought in the post-grant opposition request.

The final decision on the post-grant opposition is rendered by the BRPTO’s President. In 93.5% of the cases since the enactment of the 1996 Brazilian Patent Statute, the final decision followed the position stated in the intermediate opinion. This number rises to 95% considering the post-grant oppositions filed since 2013—when most of the BRPTO’s current examination guidelines came into force—and to 97% considering the last 12 months.

Figure 1: Maintenance of the BRPTO’s position of the intermediate opinion on the final decision

Since a final decision by the BRPTO’s President can immediately invalidate the patent, patent owners are advised to prepare and file a validity lawsuit after the issuance of the intermediate opinion with a request to stay the post-grant opposition. This transfers the discussion regarding the patent validity to the Courts, with grounds on the constitutional guarantee of access to justice.

Most post-grant opposition requests fail to follow the proper methodology when presenting the argument of obviousness. For this patentability requirement, the BRPTO applies a test comprising of the following steps: determine the closest prior art; determine the distinctive characteristics and/or the technical problem solved; and determine if the invention would have been obvious for a person skilled in the art. What these interested third parties usually do is, instead, to argue for lack of novelty based on certain prior art documents, then cite additional prior art and generally indicate the missing elements of the invention that are disclosed therein. They rarely present a combination of prior art documents.

In Zodiac v. Eisai, for instance, Zodiac presented its arguments as to why Eisai’s patent for a pharmaceutical composition would not be novel in view of four prior art documents, taken in isolation. Then they cited two additional prior art documents to argue generally they would render the invention obvious. In its reply, Eisai chose to apply the BRPTO’s test for nonobviousness. This strategy was successful, as it helped to better identify and present the distinctive features of the patented invention in relation to the state of the art. The post-grant opposition reached an end with a final decision to uphold the patent.
Data on post-grant opposition proceedings shows that the BRPTO upholds the patents as granted approximately 60% of the time.

Figure 2: BRPTO’s position on the final decision of post-grant oppositions issued since 2013

Considering the decisions issued by the BRPTO in the past year, the average timeframe for the post-grant opposition proceeding is around 2 years, as detailed below:

Figure 3: Average timeframe for post-grant oppositions in Brazil

For an interested third party, the decision to file a post-grant opposition instead of an invalidity lawsuit will rely on the urgency of the matter, since preliminary injunctions to stay the patent are not available. Nonetheless, it is possible to file an invalidity lawsuit whilst the post grant opposition proceeding is still pending, at any time. This will transfer the discussion to the courts.

For the patent owner, it is important to work on the reply to the post-grant opposition request already considering the strategy for a future litigation, and to be prepared to bring a validity lawsuit in the event of an unfavorable intermediate opinion.


The opinions expressed are those of the author(s) and do not necessarily reflect the views of the firm, any other of its practitioners, its clients, or any of its or their respective affiliates. This article is for general information purposes only and is not intended to be and should not be taken as legal advice. Please contact the author(s) if you have any questions about this article.



Rob Rodrigues

Tatiana Machado

Luiza Cotia

Yasmin Kronemberger