Lord Russell of Killowen (delivering the judgment of the Board):

This appeal raises two questions. Firstly: whether the Federal Court was right to reverse the decision of Gill J that the evidence disclosed a case of sufficient cogency to justify the equitable remedy of rectification of a contract for the sale of land on the ground of mistake common to vendor and purchaser, in including one among seven lots of land in an agreement for sale. Secondly: whether, if the Federal Court was not so justified, rectification (or its equivalent) could be ordered notwithstanding the subsequent transfer of the one lot to the purchaser and his registration as proprietor thereof, under the applicable Torrens system, and the provision of the applicable law that his title was "indefeasible."

Oh Hiam (plaintiff No. 1) was the widow of Teo Teow Guan who died in 1943. She took out letters of administration to his estate. They had five sons and three daughters, (plaintiffs 2 to 9 inclusive). Included in the estate of the deceased were six plots of rubber growing land, forming one area ("the Gombak land"), in the Mukim of Setapak, Kuala Lumpur, totalling nearly 34 acres. Also included in the es