No oral modification clause held to be legally effective

In Rock Advertising Ltd v MWB Business Exchange Centres Ltd [2018] UKSC 24, [2018] BLR 479 the Supreme Court allowed an appeal from the decision of the Court of Appeal (on which see our August/September 2016 issue pp 1–6) and held that effect should be given to a clause which provided that all variations had to be agreed, set out in writing and signed on behalf of both parties before they could take effect.