Sir Sidley Smirk Platter, Grand Sorc., (born c. 1503) was a wizard who was appointed Supreme Mugwump of the International Confederation of Wizards sometime after Pierre Bonaccord. Smirk Platter was depicted in a portrait that hung somewhere at Hogwarts School of Witchcraft and Wizardry. This portrait was painted in 1542, when he was 39 years old, as indicated by the inscription "Anno Etatis Suae 39" (anno aetatis suae is a Latin term meaning "in the year of his age").