An International Guide to
Patent Case Management for Judges

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9.6.13 Trial Types of trial

Historically, all patent trials took place in person, though dispensation could be obtained for one or more witnesses to appear via video link where it was not possible – or it was desirable – for them to appear in person. Interim hearings could be conducted remotely, for example, by telephone, but such an approach was rare in patents cases. However, the COVID-19 pandemic led to the rapid adoption of remote-trial techniques, and one of its legacies insofar as the court system is concerned is likely to be the increased use of remote technology in hearings and trials.

Trials generally do not take place during the court vacations (e.g., in August). In-person trials

A trial in person – that is, a trial where everyone appears in the courtroom – is the most common form of trial in England and Wales.

The attendees from the court will be the judge and the court clerks. The parties will be represented by their barrister(s) and solicitor(s) and may also send one or more representatives. (While most trials involve two parties – a claimant and a defendant – it is reasonably common to have multiple parties in a single trial on the same claim if convenient: for example, where there are multiple defendants.)

Witnesses will also attend on the days on which they are due to give oral evidence and may choose to attend the entire trial. Indeed, witnesses (including experts) are generally entitled to listen to the cross-examination of their opposite numbers. There usually will be a transcript writer present. Finally, English court proceedings take place in public unless the court decides it needs to sit for a (short) time in private, so there are often members of the public and press present in the public galleries. Indeed, the Patents Court judges have traditionally had a strong preference for trials to take place in open court. Hybrid trials

Hybrid trials are trials that take place partly in person and partly remotely. The most common aspect conducted remotely is the giving of witness oral evidence. Historically, a witness needed some special and justifiable reason to give evidence remotely. However, following the COVID-19 pandemic, the use of hybrid trials has increased significantly, not least because witnesses resident in foreign jurisdictions are often unable to travel to the United Kingdom.

Detailed guidance on hybrid trials is set out in Annex 3 to the Practice Direction 32 of the CPR. Importantly, despite the use of this trial format increasing, the court’s permission is required for it. The party requesting the use of videoconferencing facilities at trial must also take care in its organization for two reasons. First, there are certain practicalities that must be considered. For example, relative time zones may mean a witness is giving evidence in the middle of the night where they are based. Second, there are often local rules governing the procedure by which a person must give evidence in one jurisdiction for use in another (as is happening where the witness is based outside of the United Kingdom). Any such local rules and requirements will need to be brought to the court’s attention by the time of the pretrial review hearing and be complied with.

The increased use of remote videoconferencing in trials has also encouraged the adoption of other technologies designed to facilitate this form of trial: for example, court-specific online video platforms and software to enable the electronic sharing of bundles of documents. Fully remote trials

Fully remote trials are trials where no part of the trial takes place in person (though the judge may base themselves at the court and sit in a courtroom or in their chambers). It is likely that such trials will be rarer in the future – absent a further pandemic – and may take place only where the specific circumstances of a case mean that this approach should be preferred. Order of events and trial timetable

Directions to trial were discussed in Section 9.6.4 above, and pre-trial reviews were discussed in Section 9.6.11 above. At the pre-trial review, the scope of the trial will have been discussed (by reference to the directions). This may have included a discussion with the court about the timetable for the trial. Trials are then managed to follow that agreed timetable, subject to the need to deviate for any reasonable reasons.

In general, each side presents its case in turn, with the claimant going first unless the court orders – or there is agreement – otherwise. For example, it is common in revocation actions where there is a counterclaim for infringement by the patentee for the patentee to go first unless infringement is admitted subject to the validity of the patent. Opening written and oral submissions

Prior to the commencement of the trial, the parties will invariably prepare written skeleton arguments for their case. The purpose of these arguments is to set out the background to the parties and the case, to introduce the witnesses, to set out the issues of both fact and law that the court will be required to grapple with at trial, and to advance a party’s arguments on those issues (e.g., so-called squeezes between noninfringement and invalidity). These are then exchanged between the parties and provided to the judge, who will hear the case several days before the trial begins.136 Their importance cannot be underestimated:

As anyone who has drafted skeleton arguments knows, the task is not rocket science. It just requires a few minutes clear thought and planning before you start. A good skeleton argument (of which we receive many) is a real help to judges when they are pre-reading the (usually voluminous) bundles. A bad skeleton argument simply adds to the paper jungle through which judges must hack their way in an effort to identify the issues and the competing arguments. A good skeleton argument is a real aid to the court during and after the hearing.137

The trial then begins with short oral opening submissions from the party going first. The purpose of these submissions is to succinctly introduce the case and the live issues (which may have changed since the skeleton arguments were prepared). Opening submissions also provide the judge with the opportunity to ask questions, to clarify certain points based on the parties’ written skeleton arguments and to give directions to the parties (if needed). Sometimes the other party (or parties) will respond to the opening submissions, but only if it is necessary to do so at this stage. Long opening submissions are actively discouraged (indeed, a purpose of written skeleton arguments is to minimize the amount that needs to be said in a party’s opening submissions). Generally, opening submissions take no more than half a day, and they are often dispensed with entirely, the trial beginning with the first witness being called into the witness box. Witness evidence

Opening submissions are followed by the giving of witness evidence for the party in question. The general rule is that a party’s fact witnesses will go first, followed by their expert witnesses. However, this general rule is often disrupted by practicalities such as witness availability and is therefore frequently varied. Individuals who have signed a product and process description must also make themselves available at trial to be asked questions.

The provision of evidence at trial takes place in three steps: examination in chief, cross-examination and reexamination. However, not all witnesses are called to give evidence at trial. A witness will have given a witness statement (or prepared an expert report) that acts as that witness’ evidence in chief. Any witness who has provided a written statement upon which a party wishes to rely must be called to give oral evidence at court, but the court may order otherwise (particularly where the other party has confirmed that they do not wish to cross-examine the witness). Prior to any witness giving evidence, they will be asked to swear or affirm (at the witness’ option, and on a relevant holy text if desired) that their evidence will be true.

Fact evidence often relates to whether a particular prior use happened and was made available to the public. Such evidence should not stray into providing an opinion. Expert evidence is the primary evidence on many aspects of patent law, such as obviousness and insufficiency. If a witness is being cross-examined during a break in their evidence (e.g., over lunch), that witness is said to be in “purdah” and must not discuss the case with anyone during the break. Examination in chief

Examination in chief is conducted by the legal team of the party calling the witness. It is almost always very brief, given that the witness has already provided a written statement. Its purpose is to confirm the identity of the witness and that they still agree with their written statement. If needed, a witness also may be asked to correct small errors in their written statement. Cross-examination

Cross-examination is a key part of English proceedings and is where a witness (whether fact or expert) is questioned by the other party’s legal team. Not all witnesses will be cross-examined; it will depend upon the evidence provided and its connection to the facts in issue in a particular case.

The barrister (or solicitor-advocate) will put questions to the witness that are designed to test the witness’s written evidence. They will almost certainly be “leading questions,” meaning questions that are designed to elicit a yes or no response. The witness will also be referred to documents related to their statement or to the statements of other witnesses giving evidence in the trial. It is also possible for a witness to be presented with documents not previously in the case. Where this is to occur, the other party should provide the documents to the witness in good time before they give evidence at the trial (usually at least 48 hours) to prevent witness ambushing.

For expert witnesses, who often provide the core evidence in patents cases, there is also an option under the CPR for the provision of concurrent expert evidence,138 though it is not commonly used in the Patents Court. The process has been referred to as “hot-tubbing”: both experts are sworn in at the same time, and the judge initiates discussions between the experts on the issues in dispute and asks questions. Each issue is taken in turn. Once one issue has been addressed by both witnesses, the parties’ representatives can ask questions of the experts to clarify or test their opinions. At the end of the exercise, the judge can summarize the evidence given by both experts and ask if the summary is correct. Reexamination

After cross-examination, it is possible for the witness to be asked a few questions by the barrister (or solicitor-advocate) acting for the party who called the witness. If this occurs, the questions tend to be short and may only relate to matters arising from the cross-examination of the witness. As with the evidence in chief, the questions on reexamination must be open and cannot be “leading.” Closing written and oral submissions

After the witness evidence is complete, the parties must make their closing arguments. In patents cases, the parties will usually have the opportunity to prepare written closing submissions. These act as a summary of the evidence (both written and oral) presented during the trial as against the issues in the case that the judge has to decide. In this regard, they frequently draw attention to particular points raised by the other party where the evidence was inconsistent with that party’s case, and they also allow a party the opportunity to clarify that, in light of the evidence given at trial, a particular point is no longer be pursued. As well as addressing the evidence, written closing submissions will also address the issues of law in the case.

Written closing submissions can be very lengthy, even though, traditionally, they are written in a short period of time. In a similar way to opening skeleton arguments, written closing submissions are exchanged with the other party and lodged with the judge so that they may be read and considered. The trial timetable usually contains an adjournment of the hearing between the end of the witness evidence and the start of the oral closing to give time for the preparation of written submissions.

The parties will generally then make oral closing arguments. Usually, the party who opened the case will go last, meaning the other party presents their closing arguments first. The purpose of oral closing arguments is to supplement the written closing arguments and to present the final case that each party puts forward for the court to decide, based on the totality of the evidence presented. It is also an opportunity for the judge to ask any final questions and to clarify any issues they are considering.

The time required for the oral closing submissions is generally about one or two days but can be more in bigger cases.