Disclosure of the invention under the European Patent Convention

Article 83 of the European Patent Convention (EPC) relates to the disclosure of the invention under the European Patent Convention. This legal provision prescribes that a European patent application must disclose the invention (which is the subject of the European patent application) in a manner sufficiently clear and complete for it to be carried out by a person skilled in the art.

In order to meet the requirements of Article 83 EPC, a European patent application must contain sufficient information to allow a person skilled in the art, using his common general knowledge, to perceive the technical teaching inherent in the claimed invention and to put it into effect accordingly. In other words, the disclosure of the invention must be reproducible without undue burden, and this must be true over the whole scope of the claim. This requirement must be complied with as from the date of filing because a deficiency in a European patent application as filed, consisting in an insufficient identification of the subject-matter claimed, cannot subsequently be cured without offending against Article 123(2) EPC which provides that the subject-matter content of a European patent application as filed may not be extended.

An insufficiently clear and complete disclosure of the invention is a ground of opposition, and revocation.

Although the European Patent Convention does not exclude the patenting of "revolutionary" inventions,

The burden of proof generally lies upon an opponent to establish insufficiency of disclosure. However, "when the patent does not give any information of how a feature of the invention can be put into practice" and if the opponent plausibly argues that "common general knowledge would not enable the skilled person to put this feature into practice", the burden of proof can be shifted to the patentee to show that "common general knowledge would indeed enable the skilled person to carry out the invention."

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Wikipedia