Vanguard's head of European institutional business Simon Vanstone has died aged 53, the company has said.
The industry veteran, who previously served as European chief executive for AXA Rosenberg, joined Vanguard in 2012.
The firm described his passing as unexpected.
Vanguard Europe managing director Tom Rampulla said: "It is with great sadness that Simon Vanstone, head of Vanguard’s European institutional business, tragically passed away. Our sympathies go out to Simon’s family at this very difficult time.
“Simon made a big difference to our efforts here in Europe and on the lives of the crew. We will miss him.”
Vanstone had nearly 30 years of experience in asset management sales and marketing. Before AXA Rosenberg, he worked at State Street as a sales director.
He leaves behind a wife and three children.