Thomson Reuters names eight Keystone Law partners in its Stand-out Lawyers Guide 2026
Andrea James, Andrew Darwin & Anna McKibbin
Keynote
26 Feb 2026
•5 min read
With effect from 1 January 2026, Practice Direction 51ZH (“PD51ZH”) introduces a two-year pilot scheme in the Commercial Court, London Circuit Commercial Court of the King’s Bench Division, and the Financial List, which, broadly, gives non-parties to a commercial dispute in those courts a default right of access to just about any significant document referred to in an open hearing or at trial. This is a significant reversal of the current position where (apart from documents such as pleadings and skeleton arguments), non-parties have to apply to court and justify why they want the relevant documents.
Since just about every pilot scheme of recent times has been made permanent, it’s not particularly unrealistic to think that within the next couple of years, all documents in all High Court commercial disputes will be open for public inspection. Given the loss of commercial confidentiality and also the cost of compliance with this new exercise, it would not be surprising if commercial parties start to opt out of litigation and into arbitration as a result.
What does PD51ZH require?
PD51ZH will allow non-parties to access, as of right, “Public Domain Documents” (as defined in PD51ZH), including:
There are some exceptions, where PD51ZH does not apply, notably:
What does compliance look like?
Relevant Public Domain Documents (apart from skeleton arguments and opening and closing submissions) have to be filed on the publicly accessible part of the CE filing system within 14 days of use/reference to the relevant document at a hearing. Failure to file relevant Public Domain Documents within the relevant time frame can be sanctioned by the court ordering the filing of the relevant documents.
Filing modification orders – an illusory protection?
A party or non-party named in the relevant Public Domain Documents can apply to the court for a filing modification order (FMO) to restrict access to the document/part of it. However, the expectation is that such FMOs will be very rare. This is not surprising, as outside of price-sensitive information (and even then) it was always very difficult to persuade the court to seal the court record, and the position here is unlikely to be any different.
Insights
The big issue here is that, in principle, documents “critical to understanding of the hearing” have to be publicly disclosed. On the one hand, “critical to understanding” appears a relatively high bar, in that the materiality threshold is not “helpful to understanding” but equally, by the time you get to trial, just about every document in the trial bundle is, in some sense, “critical to understanding” the dispute/some element of it, or it would not be there. You could see a practice developing, where for the sake of simplicity and saving costs, the whole trial bundle is uploaded.
Commercial parties might well be quite unwelcomely surprised to learn that a very broad swathe of commercially sensitive materials (such as contracts or expert asset valuations) are now potentially very likely to enter the public domain at some point after a High Court dispute has arisen. In practice, the ability to prevent this happening will be limited, for all but cases in which price-sensitive or trade secret-type materials are in issue. The obvious response to this would be to provide for arbitration in relevant commercial agreements, to benefit from the much greater confidentiality available in arbitration. Alternatively, confidential mediation or other ADR processes may become more attractive, rather than issuing court proceedings. You may also see experts and/or factual witnesses pull back a little in what they are prepared to say, given this new public exposure. Clearly, both expert and factual witnesses have always had to tell the truth, but in reality, for most cases, expert and factual witnesses were never really exposed to much risk of public scrutiny. That may well still be the position for most cases. However, it is not unrealistic to think that expert and factual witnesses might, nonetheless, be rather more circumspect in their evidence, after the introduction of PD51ZH. You can quite reasonably see that potential impact as both a good or a bad thing, but one thing is for sure, it is very unlikely to have a neutral impact.
This is just a pilot currently, but given past pilots, it’s almost inevitable that it will become permanent in due course. However, it’s quite hard to see how this fits with the court’s well-founded desire to keep costs reasonable and proportionate. We say that because PD51ZH appears to introduce an entirely new workstream or even workstreams to a dispute. Just take the trial as an example. Normally, that’s more or less the end of the piece – closing submissions are made, a judgment is issued and, absent any appeal, you have to deal with the costs position at some point. However, now, it would appear that once closing submissions are finished, the parties will have to undertake a file review to identify documents “critical to the understanding of the [final] hearing”. That will come at a cost of potentially significant fees at a time when most clients will have expected their costs to go on pause, or it will require clients to divert part of their budget away from substantive work to this wholly procedural exercise. This is a cost burden that arbitration simply does not have. The English courts are a highly respected resource, both for foreign and domestic clients, yet it would be a very counter-intuitive outcome if a measure intended to promote access to information about the justice system imposed financial burdens which made access to justice itself more difficult to achieve.
If you have questions or concerns about this scheme, please contact Nick Scott.