Stiritz Family
Stiritz family's Single Family Office · St. Louis, Missouri
$500M estimated AUM
AUM figures are estimates compiled from public sources. How we source our data.
About Stiritz Family
The Stiritz Family Office is the private investment vehicle of William P. Stiritz and his family, based in St. Louis, United States, with assets estimated by an outside party at around $500 million. The family's wealth stems from Stiritz's career as a consumer-goods executive and dealmaker: he served for more than 30 years in executive positions with Ralston Purina, including as chairman, president and chief executive officer from 1981 to 1997. He later chaired Energizer Holdings and Ralcorp Holdings, and after Ralcorp announced the spinoff of its Post Foods business, Stiritz was appointed CEO of Post Holdings and also served as its board chairman. Beyond operating roles, the family invests in public equities; Stiritz personally took a 5% stake in Herbalife, making him one of its largest individual shareholders. On November 18, 2025, Stiritz announced his retirement as chairman of Post Holdings' board, effective December 16, 2025.
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Frequently Asked Questions
What is Stiritz Family?
Stiritz Family is a single family office associated with Stiritz family, based in St. Louis, Missouri.
Where is Stiritz Family located?
Stiritz Family is based in St. Louis, Missouri.
How much does Stiritz Family manage?
Stiritz Family is estimated to oversee approximately $500M in assets. As a private family office it files no public AUM disclosures, so figures are third-party estimates compiled from public sources.