Mock Videoconference Opposition Oral Proceedings

D. Brophy (IE), J. Gray (GB), B. van Wezenbeek (NL), C. Mercer (GB)

The EPO is running a pilot on the use of videoconferencing (ViCo) in opposition oral proceedings.

In this context, a mock opposition oral proceedings (OPs) was held by ViCo on May 5, 2020, organised jointly between epi and the EPO. The purpose of the exercise was to test how well the ViCo option works in inter partes proceedings to which members of the public have access.

In this report, the four epi members who took part in the mock OPS outline first the agreed format and technology, then describe our experience under various headings, both technical and human/procedural, and we conclude with recommendations to epi members.

Format and technology used


A relatively simple opposition case was agreed: a simple novelty objection was raised, which would be overcome by submitting amendments during OPs by email.

An experienced opposition division was convened by the EPO, while epi provided four participants: Chris Mercer was the patentee’s representative, Bart van Wezenbeek was the opponent’s representative, and their respective clients were David Brophy and John Gray. In addition, there were 15-20 extra attendees on the EPO side representing members of the public (and observing progress to identify issues).


The platform used by the EPO is Skype for Business (SfB). The meeting details were circulated in advance, which allowed the epi members to join the ViCo the day before in order to test connections and to see if each side could hold a private conference in parallel for discussions during the OPs both while in session and during breaks.

On the patentee side, Zoom was used for the private conference and, on the opponent’s side, Microsoft Teams was used. The members of the Division have their own private conference which they use during adjournments.


At a basic level, everyone was able to connect, and to stay connected, throughout the OPs. Everyone was able to hear what was said and the Opposition Division chair was careful to ensure that all parties were properly connected at all times, pausing proceedings as necessary to allow connectivity, audio or video issues to be resolved.

However, the overall experience was mixed. We identified several issues which are detailed below, some of which are technical and some of which relate to procedural aspects and the human user experience of conducting OPs in this medium.

Skype for Business

The epi participants are unanimously agreed that the EPO’s chosen platform, SfB, has significant limitations and that a more suitable videoconferencing solution should be found. We believe it is important that epi members take note of the limitations if they intend to participate in the current pilot of ViCo in opposition proceedings.

1. Support and access to the software
Microsoft has decided to retire SfB and pushes new subscribers to Microsoft Teams (which is not backwards compatible). This can lead to confusion when trying to find the correct software for first time use. The easiest way to access the ViCo is through a web client and one should be prompted to download the web client on trying to connect for the first time.

2. Limited gallery view
In the ViCo, the maximum number of users that can be viewed is five, plus one’s own thumbnail image. This meant that, even with just one opponent, it was impossible to see the faces of all seven agreed attendees (3 EPO, 2 representatives and 2 clients) at the same time. (At any rate, this is the situation under Covid-19, where everyone is in their own house or office.)
The epi members were agreed that, when presenting at physical oral proceedings, it can be crucial to be able to see the reactions of everyone in the room, which simply is not possible using this software. One can therefore miss important visual cues because of this technical limitation.

This also makes the software inherently unsuitable for multi-opponent oppositions. Even with a single opponent, a representative will often be assisted by one or more assistants and/or presentation may be shared between two representatives. We note that other platforms have much more generous gallery view options.

Mock Videoconference Opposition Oral Proceedings

As seen in the screenshot above, kindly provided by the EPO, the video quality can be good. This screenshot is taken from a video recording of the mock oral proceedings which can be viewed here. The layout in the video has been edited and labelled to make the proceedings easier to follow, but things are messier in real life. It can also be seen that there is a great deal of wasted (black) real estate on the screen.

The screenshot represents what could be seen if there were only the three members of the opposition division and the two representatives present and the viewer had pinned these five participants to the main screen. There is also a thumbnail on each device of the person using the device. If the members of the public had enabled their video feeds, they would have been visible in the small icons. The name shown is the name you use when entering the meeting and so it is advisable to check that it is appropriate!

3. Visibility of participants
In the mock oral proceedings, each representative was accompanied by his client. Thus, there were seven players, all at different locations. Moreover, there were a large number of “members of the public”. Using the SfB system, it is possible from the representative’s point of view to have only five full images and the representative’s image as a thumbnail. All the other attendees are shown below the main images as unlabelled icons. It is very difficult to locate the video feed of anyone who is not currently on screen. It is possible to “pin” up to five feeds so that they are permanently visible, but you are then stuck with those five faces. They are easily lost again if you switch views or decide to view a speaker who is not already pinned. Losing the feed from one of the members of the opposition division or the opposing attorney, and then finding it again and pinning it to remain visible, is a major distraction during what can already be a pressurised procedure.

Further, for non-pinned feeds, the order in which they are shown is dependent on who speaks. The feed of a person is only brought to the gallery if (s)he is speaking. In normal meetings with people you know, this normally is not a problem but, in case of oppositions, you want to see at least the faces of the opposition division (of which the second and third members hardly speak). This means that these at least should be permanently pinned to the gallery.

As said above, in case of an opposition with a three-member opposition division, a representative for the patent owner and a representative acting for the opponent, this means that the five available slots are filled. If you are one of those five (and thus would have a small feed of yourself) there is one free slot. This means that, if a party consists of more people, it is impossible to have them all on the screen together. A possible solution could be that more than one person is sitting in front of one camera, but this may bring additional problems, e.g. of control over the camera and microphone, smaller images and “social distancing” conflicts.

Members of the public could also speak until muted. The EPO later changed the permissions of the “public” to mute them. There is also a chat function which, during the oral proceedings, was used by the members of the public. This highlighted the need for the EPO to clearly define in advance permission levels for everyone attending the oral proceedings. However, it could be envisaged that, during the oral proceedings, some members of the public or members of the parties should be allowed to speak. It is not known if, during the oral proceedings, the permission levels could be changed and/or whether, for these members, the microphone can be muted/unmuted.

4. Chat window
A text chat channel is available. Everything typed here is visible to everyone on the ViCo, including members of the public. There is no private chat available. Sending messages using a different piece of software (e.g. Zoom or Teams) for a private conversation is certainly possible but the attorney may not see this when concentrating on the main ViCo window.
Most alternatives to SfB cater for private chat messages.

One of the “members of the public” also used the chat window to comment on technical issues of patentability during the arguments which, of course, is something that should be prevented.

5. Visual aids and screensharing
In conventional oral proceedings, parties are frequently permitted to use a flipchart or whiteboard, will point to drawings (enlarged or normal size depending on the room layout) or will show and share versions of drawings with highlighted parts to assist in understanding. The simple case chosen for the mock OPs did not lend itself to such visual aids. The opposition division were reluctant when asked to share a proposed claim amendment onscreen, because then the video images are replaced by the shared screen. Again, this seems to require looking into another ViCo platform where video images can be displayed together with screensharing.

We are aware that introducing such materials and explanations may give rise to admissibility objections but does not see that these are different in principle from the questions that arise when such materials form part of a party’s presentation in physical OPs. Visual aids in some cases are key to assembling/conveying the facts or arguments that are decisive for the case.
We therefore believe that clarity is needed from the EPO as to whether, and in what circumstances, screensharing and the sharing of visual materials is to be permitted.

6. Interpreters
No interpretation was involved in the mock OPs and we understand that OPs requiring interpretation will not be eligible for the current pilot which the EPO is running. It is apparent that SfB would not be capable of handling any involvement of interpreters. We are aware of specialist solutions that can do this (which has been tried for example in the Administrative Council).

7. Parallel private channels
As noted above the epi participants used both Zoom and Teams as a "side channel” to allow for private conversations by text, audio and video while the OP ViCo was live. In general, we found that this worked well although there were a few issues to be aware of.

  1. Each user’s experience was specific to their individual hardware and software set-up. When Teams was used as a side channel, we found that one attorney’s computer muted the microphone within the ViCo OP, while the other’s did not. It is therefore crucial to test the side channel in advance if at all possible.
  2. During adjournments, stopping the video feed and muting the audio feed within SfB freed up the same hardware to be used in the side channel. This too may be hardware-dependent and should be tested. Best practice is to establish the SfB call to the EPO before opening the side channel and to keep the SfB ViCo open throughout.
  3. Two screens should be used if at all possible. This allows the SfB ViCo window to always be in full size view, even if there is a parallel text chat, if one needs to use email or look at documents.
  4. The biggest danger with a side channel is that there is “leakage” into the OP ViCo, which remains fully active during adjournments. Users need to be scrupulous about muting within each application whenever they are not actually speaking and intending to be heard.
  5. The biggest limitation in the side channel is that video and audio are only usable during the interruptions. If the team members are not in the same room, then (unless they have a separate device and adequate bandwidth) they cannot see and hear each other while the OPs are in progress.

Filing of documents and amendments
The Patentee filed an amendment to restore novelty. The procedure was that this was sent to the members of the opposition division by email. One member of the opposition division then shared it with the other representative. The representatives had to then share it in a separate email with their clients.

This procedure could be improved by having an email thread that includes all parties (and their accompanying persons) and all members of the division. Any documents that need to be “handed out” could then be sent as a “reply to all”, greatly reducing the complexity of the procedure.

We also felt that requiring one of the examiners to carry out all the administrative tasks during the OPs was too burdensome and that the division should be supported by a formalities officer throughout the OPs.

Signatures, identification and data privacy
When filing amendments, the EPO required the representative to sign the email in a particular format. It is suggested that, if an email thread were created at the opening of OPs by an EPO official, then it would be immediately evident that a simple email sign-off from any of the parties would sufficiently identify their submission (given that it is invariably confirmed orally on the record that they have sent a document or an amendment).

The representatives were required to identify themselves at the start of proceedings e.g. using an EPO attorney’s badge or passport held up to the video camera. Given the presence of members of the public, this could involve sharing sensitive information with a wide and anonymous group. Thought should be given to improving this procedure. The chair of the division was careful to interrupt a representative trying to establish the correct spelling of an email address for another division member, due to GDPR concerns, and the same considerations should apply to all personal data that need to be shared.

In the mock OPs, both representatives were epi members. However, it is possible for employees or lawyers to represent in OPs. It was not clear how this would be dealt with at ViCo OPs.

General clarity on procedures
It would be helpful for parties taking part in ViCo OPs to be provided with a document summarising the procedure, with sections covering the operation and control of the software, signatures, how to make amendments, the rules applying to text chat, how to interrupt or draw attention to problems, and so on. This would allow users to familiarise themselves with the procedure and provide a document for the chair to refer participants to during the OPs.

Recommendations and Advice

Anyone considering taking part in ViCo opposition OPs should think very carefully about how the limitations set out above will affect their presentation and participation.

At present, opposition OPs are only being held with the consent of all parties. If you believe that your presentation will be adversely affected by the shortcomings outlined above, then ViCo OPs may not be suitable.

Conversely, the epi participants were agreed that, for simple cases, where the numbers on both sides are very limited (preferably just one attorney with no accompanying persons or clients) and where one does not anticipate needing to rely on visual aids for your presentation, then ViCo OPs may provide an acceptable alternative.

It is imperative to thoroughly test one’s connection in advance, using the exact equipment and software that you intend to use on the day. The EPO will facilitate test calls which can be arranged by contacting the EPO Serviceline or by e-mail Make use of this opportunity to also test any side channel you are considering using (e.g. a parallel video or voice call from the same machine using different software). Technical requirements are explained at The EPO has also published further guidance for those using ViCo oral proceedings at Be aware that if your connection is unsatisfactory at any point, the EPO should be alerted immediately, so that proceedings can be paused.

Use two screens, headphones and a microphone if available. Consider in advance whether you want to sit alone in a room or with other people (your client or colleagues?) and whether these should then be visible on the screen or not.