A well-crafted Part 36 offer can shift the costs burden decisively in your favour. It's one of the sharpest tools in the litigation toolkit. But the recent decision in Cooper and others v Ludgate House Ltd [2026] EWHC 484 (Ch) is a reminder that overcomplicating an offer with non-monetary conditions can strip away the very costs protection you were trying to secure.

What happened?

The Claimants, Mr Cooper and Mr and Mrs Powell, were the owners of flats within a development that was adversely affected by the Defendant's building works. They commenced proceedings alleging an infringement of their right to light and sought an injunction to halt the development or, alternatively, damages. Before trial, in November 2024, the Defendant made Part 36 offers of £500,000 to each Claimant. 

At trial, the court refused to grant injunctive relief but awarded damages to the Claimants in the sums of approximately £397,000 to Mr Cooper and £568,000 to the Powells. On paper, Mr Cooper's award fell approximately £100,000 short of that figure and the Defendant accordingly contended that it had beaten its offer and was entitled to the costs consequences under CPR 36.17(3). 

However, the Defendant's offers came with a catch. As a condition of acceptance, the Claimants would have been required to relinquish not only their existing claims but also any future entitlement to statutory compensation under section 204 of the Housing and Planning Act 2016 in relation to a neighbouring site the Defendant's associated company planned to develop. The Claimants were, in effect, being asked to forfeit prospective rights that bore no direct connection to the claim before the court and that were, by their nature, incapable of quantification. 

The court's decision

Fancourt LJ held that the court could not properly assess the Defendant's offers by a straightforward comparison of the headline cash figures. The burden of proving that the recipient of the offer had failed to obtain a more advantageous judgment sat with the offeror, in this case the Defendant. Where a Part 36 offer required the offeree to surrender something beyond the subject matter of the extant proceedings, the court must evaluate the value of that additional element. In the present case, the future statutory compensation rights were inherently unquantifiable as they related to a development that hadn't yet taken place. Accordingly, the offeror's burden had not been discharged and so the Part 36 costs consequences did not apply.

What this means for your Part 36 strategy

For offerors, the message is clear: keep your Part 36 offers simple and quantifiable. It's tempting to extract broader concessions through a settlement offer, such as waivers of future claims or releases over unrelated matters. Commercially, that may make sense. But Cooper shows the litigation risk. If the court can't put a reliable figure on a non-monetary element, it won't determine whether the offer was beaten, and the costs protection of the Part 36 regime could be lost.

If you're on the receiving end of an offer bundled with hard-to-value conditions, Cooper gives you a strong basis to resist the costs consequences even if your damages award falls below the quantifiable headline figure.

Our view

Cooper is a useful reminder that the efficacy of a Part 36 offer turns not merely on the headline figure, but on the clarity and simplicity of the offer as a whole. An offeror who seeks to use the Part 36 regime as a vehicle for extracting wide-ranging concessions risks undermining the very mechanism upon which it relies. The safest approach remains a straightforward, readily quantifiable offer that leaves the court in no doubt about the comparison it is required to make.