99.99997 th percentile; IQ 175 sd15, IQ 180 sd16
≥ 5 standard deviations above the mean
51st WIN member society (since 07/2015)
Extreme Sigma Korea(ESK) was founded on July 25, 2012 by Hankyung Lee, M.D, with the aim to gather the people who have high level of intelligence above IQ 220 sd24 or IQ 175 sd15 of the unselected adult population in Korea. FSK provides an intellectual private forums that ESK members are allowed to share ideas and opinions for intellectual life.