An extended disclosure case under PD 57AD
A worked PD 57AD extended disclosure exercise: list of issues, disclosure review document, custodian collection, technology assisted review and production, with a timeline, indicative costs and the questions litigators ask.
A Business and Property Courts claim over a failed acquisition. Eight custodians, four years of email and Teams, a shared drive and a deal room. The parties must agree a disclosure review document and a model for each issue, and the court expects a proportionate, costed proposal.
This page sets out what happens at each stage, what it costs and the questions counsel ask before instructing. The figures are indicative and exclude VAT.
§ Timeline
What happens, and when
- Week 1
Hold, custodian map and data survey
Confirm the hold, interview the custodians, and survey what exists across mailboxes, chat, shared drives and the deal room so volumes are known before models are agreed.
- Week 2
Disclosure review document
Populate section 1A and section 2 with real volumes and costs, propose a model per issue, and set out the search terms, date ranges and custodians we say are proportionate.
- Week 3 to 4
Collection
Tenant side collection of mailboxes and Teams, shared drive capture and deal room export, all with chain of custody and a reconciliation against the survey.
- Week 4 to 5
Processing and early case assessment
De-duplicate, thread and index, then test the agreed terms so the review population and cost can be reported to the other side and the court.
- Week 6 to 10
Review
Technology assisted review with continuous active learning where volumes justify it, privilege review, and quality control sampling recorded for the disclosure certificate.
- Week 11
Production and certificate
Produce in the agreed format with the required metadata fields, and provide the process evidence behind the disclosure certificate.
§ Costs
What each stage costs
Indicative ranges for a matter of this shape, excluding VAT, court fees and your own review time. Every instruction gets a written stage by stage budget after the first call, and we do not move to the next stage without approval.
| Stage | Indicative fee | What it covers |
|---|---|---|
| Data survey and DRD support | £2,000 to £5,000 | Custodian interviews, volume survey and populated disclosure review document. |
| Collection | £3,000 to £8,000 | Eight custodians across mail, chat, shared drive and deal room. |
| Processing and hosting | £12 to £25 per GB, then hosting | De-duplication, threading, indexing and monthly hosting per GB. |
| Technology assisted review | £3,000 to £9,000 | Model set up, training rounds, validation and reporting. |
| Review platform support | £2,500 to £7,000 | Workflow build, search term testing, redaction and quality control. |
| Production | £1,000 to £3,000 | Agreed load file format, metadata fields and production log. |
§ FAQs
Questions counsel ask
- Which model should we ask for?
- It is issue by issue. Model C requests work where the documents are narrow and known, Model D where the issue turns on a broad narrative. We help you argue the choice with real volume and cost figures rather than assumptions.
- Does the court expect technology assisted review?
- Where volumes are large, yes, and PD 57AD requires you to consider it. The important part is being able to show the validation results, which we record as the review runs.
- How do we keep the costs proportionate?
- Survey before you promise anything, test the terms on real data, and phase the review by issue. Most cost overruns come from agreeing a scope in the DRD before anyone has measured the data.
- What does an eight custodian extended disclosure exercise cost?
- Typically £25,000 to £60,000 excluding your own review time, depending on volume and whether technology assisted review is used. You get a stage by stage budget that maps to the DRD.
Commercial disputes →The eDisclosure guide →Review →
§ From the Case Builder blog
- Scoping extended disclosure so it does not run away
A working method for Practice Direction 57AD: agree the issues, sample before you promise, and keep the search narrow enough to defend.
- What a judge expects from a disclosure witness statement
The statement supporting your search, collection and review decisions is the document that gets tested. Write it for the court, not for the file.
Bring us in early.
Defensibility is built, not retrofitted.
Whether you are responding to a regulator, preparing for disclosure, or scoping an internal investigation, start the chain of custody with a short, confidential conversation.