Assensus Ltd v Wirsol Energy Ltd (Re Consequential Matters) [2025] EWHC 503 (KB)

Unsuccessful Claimant argued that Defendant ought to receive only 70% of its costs because, inter alia, the failure to mediate was unreasonable. Court found that the decision not to mediate was not unreasonable because "Whilst I do not consider that the costs of ADR would have been disproportionate or cause prejudicial delays, in light of the offers on the table, I consider it very unlikely indeed that ADR would have been successful. Indeed, Mr Khan’s initial submissions accepted that ‘Mr McCarthy’s rejection of £257,000 £157,500 suggests that the mediation may have failed…’. I agree (save that, of course, there was no ‘rejection’ of £157,000, as though it was an offer to reject. This was the conclusion of Wirsol’s expert as to the potential market value of a bonus, on the assumption that an entitlement existed, which it did not). As made clear in the Judgment, Mr McCarthy had already refused a discretionary bonus of £257,000. The offer of Part 36 Offer of £100,000, whilst ultimately still generous in light of Assensus’ contractual entitlement, plainly significantly below a sum previously rejected, and the gulf between the parties therefore remained very significant."

Question whether decision as to whether conduct was unreasonable can be judged with the benefit of hindsight or whether the judge should be looking at the facts known to the parties at the time they refused to mediate?