Geoffrey Denis Erskine Russell, 4th Baron Ampthill, CBE, PC (15 October 1921 – 23 April 2011), was a British hereditary peer and businessman, whose paternity and succession to the peerage were famously disputed in the "Ampthill baby case". His father, John Russell, 3rd Baron Ampthill, had petitioned to disclaim paternity whilst divorcing Russell's mother, Christabel Hulme Hart, in 1923, claiming non-consummation. The petition was rejected on appeal and Russell's mother was granted a declaration that he was legitimate.