http://www.bailii.org/ew/cases/EWHC/QB/2016/389.html

Various issues regarding disclosure arose in this case. One issue was whether the defendants could exclude from their review all documents which had given rise to a "unique hit" (where a document is identified as the result of a keyword search by responding only to one search term rather than more than one, a "unique hit" is said to have occurred). It was explained that 25 terms which had generated unique hits within the 21,000 document set had been shown to have required no documents to be disclosed. A further 4 terms had resulted in less than 1% of documents reviewed needing to be disclosed.

It was estimated that this approach would reduce the documents to be reviewed from 21,000 to 13,000. Although the claimants agreed the exclusion of the 25 terms, they did not want to exclude the other 4. This was on the basis that just one document within the disclosable documents might reveal something of significance.

Foskett J agreed with the claimants, holding that: "It is difficult, in my view, to justify a simple percentage or other mathematical analysis to this kind of exercise. Where arguably seriously culpable behaviour has taken place, it is unlikely that it will be revealed in a significant number of documents".

The judge refused, though, to widen the list of custodians to include secretaries: "I acknowledge the possibility that a secretary or PA may have created a document at the instance of the person for whom she was working, but it would be highly surprising if that document, or at least its existence, would not be revealed in the searches to be made of the communications of those for whom they were working".

The judge also agreed that the trial date would have to be vacated to allow disclosure to be completed and for a fair trial to take place. He stressed that he had been reluctant to do so, though, not just because of the interests of the parties to this case, but also the interests of other parties who would have wished to have their case heard on the same trial date.