John Rogers’s Ariel Investments has been at various times the largest shareholder in Sotheby’s. But the dramatic rise in price brought on by activist interest and a booming market has caused him to sell some of his stake, according to NASDAQ:

As of Sept. 30, 2013, John Rogers reduced his position by 29.32%, unloading 917,170 shares at an average price of $44.52 per share, for a gain of 17.8%.

The current share price is around $51.93, with a change from average up 17%.

Over a remarkable five-year history, John Rogers gained 104% on 3,689,083 shares bought at an average price of $25.67 per share. Selling 8,289,427 shares at an average price of $25.14 per share, he made a gain of 109%.

Ariel Capital’s John Rogers Trims Sotheby’s, DeVry, Hospira, IPG, Others (NASDAQ)