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Magic Disclosure: How to Make Prior Art Disappear

By Thomas Hoolaghan, Associate

In determining whether an invention claimed in a patent application is new and inventive, the European Patent Office (EPO) can reference any information made available to the public prior to the filing date of the patent application. As one would imagine, the pool of information at the EPO’s disposal is vast and includes any information made available through written or oral description.

With the dawn of the Internet age, it has never been easier to make information available to the public. Indeed, the simple publication of information (such as this article) on a publicly accessible website constitutes a further addition to the ever-growing reservoir of information which can be used to assess the novelty and inventiveness of subsequently filed patent applications.

However, is there ever a scenario in which this reservoir of information can be depleted? That is, could information which was previously made “available” to the public be made “unavailable”?

This was the issue contemplated in a recent case (T 3000/19) handled by an EPO Technical Board of Appeal, in which the Board had to determine the availability of information previously disclosed via the Internet.

The Application

European Patent Application EP2537358 was directed to an invention concerning a mobile wireless communications device and a method for searching data on data sources associated with registered applications.

During examination of the application, the examining division of the EPO cited a piece of prior art which related to a disclosure in a video titled “Mac OS X Leopard Overview: Mac OS X Leopard Dictionary”. The video was posted on YouTube in 2008, one year prior to the effective filing date of the application. The examining division objected that the subject-matter of claim 1 of the application lacked an inventive step over the video disclosure when considered in combination with “common general knowledge and notoriously known features”. In other words, the information made available in the video, when combined with common general knowledge, was considered to render the claimed invention obvious to a person skilled in the art. As a result, the examining division refused the application. The applicant appealed this decision.

The Appeal

When considering the appeal against the decision to refuse the application, in T 3000/19, the Board of Appeal found that the URL, cited by the examining division for accessing the YouTube video, was no longer functioning. That is, the video was no longer available on the YouTube website, and thus the Board were not able to fully analyse the disclosure included in the video.

Instead, the electronic file of the case only included some screenshots of the video, and comments about the video’s content by both the examining division and the appellant. The Board found that the screenshots and comments contained in the electronic file were simply insufficient for reviewing the relevance of the video disclosure. Since the video evidence was no longer accessible, the Board was unable to analyse the significance of the disclosure to the inventiveness of the claimed subject-matter, and thus could not assess whether the contested decision was correct. Consequently, the Board concluded that a substantial procedural violation had taken place and the case was remitted to the examining division for further prosecution.


In its decision, the Board noted that EPO Guidelines for Examination B-X, 11.6 specify certain procedures for handling prior art concerned with internet disclosures. In particular, the guidelines state that relevant video and/or audio media fragments available on the internet should be converted into a non-patent literature citation, and that the bibliographic data for such disclosures should contain the URL of the original location on the internet. The Guidelines for Examination also state that fragments of a video disclosure on the internet should be cited as a screenshot of the first page of the internet citation.

Therefore, even though the information recorded by the EPO was insufficient for determining the relevance of the video disclosure, the Board found that the examining division had indeed followed the recommended EPO guidelines for recording the video disclosure as evidence.


Thus, this case exposes a flaw in the EPO’s procedure for handling internet disclosures, specifically when those disclosures provide information which cannot be fully captured by means of a screenshot. In fact, the Board acknowledged this flaw in section 13 of its decision, stating that the procedure set out in the guidelines “is insufficient for preserving video evidence and guaranteeing its accessibility over time as needed for EPO proceedings or for further judicial proceedings before the boards of appeal of the EPO or national courts (Article 131(1) EPC)”.

To add insult to injury, this is not the first time that the loss of the video in question has caused trouble. In T 3071/19, the Board of Appeal were again faced with the issue of the same disappearing YouTube video. In both cases, the objection to inventive step could not be assessed since the relevant prior art was no longer available, leaving the Boards with no option but to remit the cases to the examining division for further prosecution.

At the time of writing, it is not yet clear whether these cases will motivate the EPO to update their procedures for collecting, storing, and preserving relevant internet disclosures. It is noted that the Board did refer to the Council of Europe’s guidelines on using electronic evidence, which explicitly state that a screen printout from a browser is not considered reliable evidence, and instead recommends that electronic data be “retained in its original format”. However, the EPO are not currently bound by these guidelines.

In any case, the decision of the Board of Appeal in these instances highlights the importance of accurately recording evidence in patent proceedings. Indeed, any party interested in challenging the patentability of a patent, or patent application, should ensure that the relevant evidence is accurately stored such that its contents can be sufficiently verified. At the very least, the decisions described above prove that mere URLs and screenshots are not always sufficient evidence for assessing information disclosed in a video, and that information that was once made available to the public really can be made unavailable again.

This is for general information only and does not constitute legal advice. Should you require advice on this or any other topic then please contact or your usual HLK advisor.

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