A legendary figure in Wall Street's trading history has passed away. Robert Mnuchin, who spent over three decades reshaping how block trades work at Goldman Sachs, died at 92. His son went on to lead the U.S. Treasury under President Trump's first administration, but the elder Mnuchin's real legacy was in the markets themselves. During his 33 years on the Street, he fundamentally changed how large-scale equity trades were executed—a foundation that still influences financial markets today. His contributions to institutional trading mechanics remain a benchmark for how Wall Street evolved.