Daniel 'Dan' Sundheim is an American billionaire investor and the self-made founder and Chief Investment Officer (CIO) of D1 Capital Partners, a global investment firm renowned for its large-scale investments across public and private technology markets. His background is rooted in elite finance: he graduated from the Wharton School of the University of Pennsylvania in 1999 with a B.S. in Economics.

His career began in the highly analytical world of private equity at Bear Stearns' Merchant Banking Group. However, his rise was cemented during his 15 years at the prestigious Tiger Cub hedge fund, Viking Global Investors, where he became the CIO, managing a diversified portfolio of billions of dollars. This intense experience in public market trading and managing massive capital positioned him for his entrepreneurial leap.

Daniel Sundheim founded D1 Capital Partners in 2018 with a clear vision: to create a hybrid firm that operates across both public and private markets, combining the talent and operational excellence of a large hedge fund with the flexible mandate of a long-term investment firm (a quasi-family office model). D1's strategy is highly concentrated and focused on high-growth companies in the global internet, technology, media, and consumer sectors. The firm quickly amassed massive assets under management (AUM), reaching approximately $20 billion.

His wealth is secured by the immense success of D1's investments in the private market—where the majority of its capital is deployed. Notable private investments include a large stake in Instacart. Although D1's public fund has experienced significant volatility (a 27 percent return in 2021 followed by a 30 percent decline in 2022), Sundheim's long-term vision and private market success cement his status as a major multi-billion dollar financial executive.

Daniel Sundheim's philanthropy is structural and focuses on arts, culture, and healthcare. He serves as a trustee of the Museum of Modern Art (MoMA) and NYU Langone Medical Center, leveraging his immense wealth to support cultural and health institutions in New York.

His structural contribution is tied to D1's role in funding and accelerating the growth of major global technology companies, driving innovation in the internet and consumer sectors. His wealth supports causes related to Jewish heritage and community welfare in Miami and New York.

Daniel Sundheim maintains the high-powered, intellectual style of a hedge fund CIO. His attire is consistently formal and high-quality, favoring bespoke tailored suits. His aesthetic is one of confident, focused financial expertise.

Residing in New York City, his luxury is the immense security of his multi-billion dollar fortune, which affords him the autonomy to manage a massive hybrid investment fund. His life is defined by high-stakes investment and his commitment to applying quantitative and fundamental analysis to the most complex technology opportunities.