Practice – Disclosure and inspection of documents. The collateral purpose rule under CPR 31.22 related to documents already disclosed and produced, not to the preceding process of disclosure and production, and it was based on different policy considerations. The Financial List ruled that none of the objections to the disclosure of documents (including third party material) which the Serious Fraud Office (SFO) had provided to the defendant, Tesco plc, had been such as to warrant an order preventing their production in proceedings brought by the claimants for compensation concerning losses allegedly suffered due to Tesco plc's alleged false accounting. The documents had been provided to Tesco plc for the purpose of negotiations about a deferred prosecution agreement eventually concluded between the SFO and Tesco plc's subsidiary in 2017. The court ruled that, in circumstances where disclosure and production were sought from an existing party to the proceedings, the test of necessity, expressly retained in CPR 31.17(3)(c), and the test in CPR 31.22 (concerning restrictions on collateral use), did not apply. It held that the question was whether, in the particular circumstance, the objective of dealing with the case justly and at proportionate cost could be achieved without disclosure of the relevant documents, and that, on the facts, it would not be just to deny the claimants production of the documents, which were likely to be of considerable litigious advantage to them.