World Intellectual Property Organization

Opposition systems and related mechanisms

Many national and regional patent systems provide opposition mechanisms which aim at improving the quality of patents by providing third parties an opportunity to oppose the grant of a patent within a certain period of time. An opposition mechanism may be available either after the publication of a patent application or soon before the grant of a patent (pre-grant opposition) and/or after the grant of a patent (post-grant opposition) depending on the applicable law. While the design of opposition systems may differ from one country/region to another, the common objective is to provide a simple, quick and inexpensive administrative mechanism that increases quality by providing additional input to the process.

Many countries provide other, similar mechanisms, such as third party observations, re-examination and administrative revocation and invalidation. In general, they allow third parties to intervene in the patent examination process before the grant of a patent, or to challenge a patent after its grant, without having to resort to the courts. The following documents provide information on the work of the SCP regarding opposition systems and related mechanisms.

SCP Working documents on the topic

  • Report on the International Patent System (SCP/12/3 Rev.2)
  • Opposition Systems (SCP/14/5)
  • Opposition Systems (SCP/17/9)
  • Opposition Systems and other Administrative Revocation and Invalidation Mechanisms (SCP/18/4)

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