Could A Feature Not Readily Apparent On Reading A Prior Art Document Only Once Count As Having Been Disclosed?

In a recent EPO Board of Appeal decision, T 2517/11, the Board has reaffirmed that for a feature to be deemed disclosed in a document, it is not necessary for the feature to be readily apparent on reading the document only once. Furthermore, the skilled person does not need to have specific motivation to investigate the existence of a "hidden" technical feature in the prior art.

In the case in question, Orange had applied for a patent for a method of transform-based coding/decoding of digital signals. The Examining Division had refused the application on the ground of lack of inventive step under Article 56 EPC.

Orange appealed the decision of the Examining Division, arguing that one of the features of the prior art on which the Examining Division had based their objections could only be determined after mathematical analysis and not solely from reading the text of the disclosure. In particular, the appellant argued that the skilled person would not be motivated to