Stephen (Steve) Mandel Jr. is an American hedge fund manager who founded Lone Pine Capital in 1997, which mostly invests in technology companies. A Connecticut resident, Mandel’s net worth was estimated at $2.5 billion in 2024, down from a high of $3.9 billion in 2022, likely due to his accelerated political and charitable giving. Mandel is a prolific donor to Democratic politicians and donates millions to Democratic leadership PACs each election cycle. He and his wife Susan Mandel founded the Zoom Foundation, which controls $1.2 billion in assets and contributes most of its disbursements to donor-advised funds. ^{1 2}

Mandel was described by Inside Philanthropy as a “black box billionaire” meaning that he utilizes contributions from his foundation to donor-advised funds to meet distribution requirements and mask the organizations that receive the vast sum of his giving in the United States, circumventing traditional requirements for private foundations to disclose their grantees. ³

Early Life and Career

Stephen P. Mandel Jr. attended Philips Exeter Academy for high school followed by Dartmouth College which he graduated from in 1978. He met his wife, Susan Zadek Mandel, when the two were classmates at Harvard Business School. He later served as chair of the board of trustees at Dartmouth. ⁴

In 1997 Mandel founded Lone Pine Capital, a “long/short and long-only equity money manager.” Prior to founding Lone Pine, he was a managing director and consumer analyst at Tiger Management Corporation, mass-market retailing analyst at Goldman Sachs, and consultant at Mars and Company. He is among several notable alumni of Tiger Management Corp known as the “Tiger cubs” who went on to found successful hedge funds with the backing of Tiger Management founder Julian Robertson. ⁵

Mandle stepped away from active management of Lone Pine in 2019 and in 2021 his net worth reached a high of $3.9 billion; it was estimated at $2.5 billion in 2024, likely due to his accelerated political and charitable giving. He has sat on the boards of Teach for America and the Environmental Defense Fund. ⁶

Political Giving

Stephen Mandel is a prolific donor to Democratic political committees and candidates. Since 2020, he has made multiple seven-figure donations to Democratic campaign PACs including $3 million to the Senate Majority PAC, $5 million to Future Forward USA, $2.1 million and $2 million to American Bridge 21st Century in 2021 and 2022, $1.5 million to Forward Majority Action, and $1 million to the Lincoln Project, a PAC formed by former Republicans opposed to Donald Trump’s presidential campaigns. ⁷

Foundation Giving

In 2001, Stephen and Susan Mandel founded the Zoom Foundation (which bears no relation to the video conferencing platform). The Foundation has drawn criticism for directing virtually all its annual giving to donor-advised funds, directing $58.4 million of $60.1 million in 2023 to the Fidelity Charitable Gift Fund, effectively allowing the foundation to meet its annual disbursement requirements while being able to distribute the funds over time without disclosing the ultimate recipient. ⁸

Mandel was described by Inside Philanthropy as a “black box billionaire” meaning that he directs contributions from the Zoom Foundation to donor-advised funds that receive the vast sum of his giving, circumventing traditional requirements for private foundations to disclose their grantees, as well as allowing the foundation to meet its annual legally required disbursements. ⁹

Inside Philanthropy separately reported that Mandel and his wife Susan granted nearly half a billion dollars to the foundation from 2014 to 2024 with 99.9% going to the Fidelity Charitable Gift Fund. An investigation from Inside Philanthropy revealed some online acknowledgments from the Zoom Foundation indicating that some funds had been disbursed from the Fidelity donor-advised fund including to the Environmental Defense Fund, Teach for America, and Blue Meridian Partners. ¹⁰

A spokesperson for the Mandel family office stated that the foundation has a “no-press policy and does most of its giving confidentially.” ¹¹  

Other recipients identified include Teach for All, Summer on the Hill, Connecticut education nonprofit ConnCAN, SummerSearch, Waterside School, gap year group Omprakash, and Care.org. ¹²  

The Mandels and Zoom Foundation also place an emphasis on environmental funding and in addition to funding the Environmental Defense Fund, the foundation has appeared to fund the Columbia Law School’s Center for Public Research and Leadership, and funded a Columbia report detailing which U.S. states “are least prepared for climate-change fueled flooding” in 2015. The foundation also participates in the Biodiversity Funders Group. ¹³

The foundation has also supported the Campaign Legal Center. ¹⁴

1. “Stephen Mandel Jr.” Forbes. Accessed August 1, 2024. https://www.forbes.com/profile/stephen-mandel-jr/
2. Kavate, Michael. “Meet the Black Box Billionaires: Are These America’s Most Secretive Megadonors?” Inside Philanthropy. July 10, 2024. Accessed July 27, 2024. https://www.insidephilanthropy.com/home/2024/7/10/meet-the-black-box-billionaires-are-these-americas-most-secretive-mega-donors
3. Kavate, Michael. “Meet the Black Box Billionaires: Are These America’s Most Secretive Megadonors?” Inside Philanthropy. July 10, 2024. Accessed July 27, 2024. https://www.insidephilanthropy.com/home/2024/7/10/meet-the-black-box-billionaires-are-these-americas-most-secretive-mega-donors
4. “‘Visible and Accessible’: Chair Steve Mandel ’78 on Priorities for the Board.” Dartmouth. November 28, 2010. Accessed August 1, 2024. https://home.dartmouth.edu/news/2010/11/visible-and-accessible-chair-steve-mandel-78-priorities-board
5. “Stephen Mandel Jr.” Forbes. Accessed August 1, 2024. https://www.forbes.com/profile/stephen-mandel-jr/
6. “Stephen Mandel Jr.” Forbes. Accessed August 1, 2024. https://www.forbes.com/profile/stephen-mandel-jr/
7. Donor Lookup: Stephen Mandel.” OpenSecrets. Query Conducted August 1, 2024. https://www.opensecrets.org/donor-lookup/results?name=Stephen+Mandel&order=desc&sort=A
8. Return of a Private Foundation (Form 990-PF). Zoom Foundation. 2023. https://projects.propublica.org/nonprofits/organizations/61600601/202323179349101377/full
9. Kavate, Michael. “Meet the Black Box Billionaires: Are These America’s Most Secretive Megadonors?” Inside Philanthropy. July 10, 2024. Accessed July 27, 2024. https://www.insidephilanthropy.com/home/2024/7/10/meet-the-black-box-billionaires-are-these-americas-most-secretive-mega-donors
10. Kavate, Michael. “This Hedge Fund Billionaire is a Black Box. Here’s What We Know About His Giving.” Inside Philanthropy. October 13, 2022. Accessed August 1, 2024. https://www.insidephilanthropy.com/home/2022/10/13/this-hedge-fund-billionaires-foundation-is-a-black-box-heres-what-we-know-about-his-giving
11. Kavate, Michael. “This Hedge Fund Billionaire is a Black Box. Here’s What We Know About His Giving.” Inside Philanthropy. October 13, 2022. Accessed August 1, 2024. https://www.insidephilanthropy.com/home/2022/10/13/this-hedge-fund-billionaires-foundation-is-a-black-box-heres-what-we-know-about-his-giving
12. Kavate, Michael. “This Hedge Fund Billionaire is a Black Box. Here’s What We Know About His Giving.” Inside Philanthropy. October 13, 2022. Accessed August 1, 2024. https://www.insidephilanthropy.com/home/2022/10/13/this-hedge-fund-billionaires-foundation-is-a-black-box-heres-what-we-know-about-his-giving
13. Kavate, Michael. “This Hedge Fund Billionaire is a Black Box. Here’s What We Know About His Giving.” Inside Philanthropy. October 13, 2022. Accessed August 1, 2024. https://www.insidephilanthropy.com/home/2022/10/13/this-hedge-fund-billionaires-foundation-is-a-black-box-heres-what-we-know-about-his-giving
14. Kavate, Michael. “This Hedge Fund Billionaire is a Black Box. Here’s What We Know About His Giving.” Inside Philanthropy. October 13, 2022. Accessed August 1, 2024. https://www.insidephilanthropy.com/home/2022/10/13/this-hedge-fund-billionaires-foundation-is-a-black-box-heres-what-we-know-about-his-giving