The landscape architect was at the hospital the night her daughter Lucy was found unconscious in February. She has never given an interview, so most of what is known about her comes from public documents and news reports.
Karen Ann Herskovitz was already at Elmhurst Hospital in Queens when her former husband, Bill Ackman, got there in the early hours of 6 February 2026. Their eldest daughter, Eloise, had found her sister Lucy, then 26, unconscious on the floor of her flat in Brooklyn and called 911. Doctors found a brain haemorrhage and operated within hours.
Ackman’s post about that night, published on X on 19 August, has been viewed about ten million times. He wrote that he arrived about five minutes after the ambulance “to join Eloise, Lucy’s mom, and a friend”. The post does not name her.
Herskovitz, a landscape architect, was married to Ackman for 22 years and was widely known as Karen Ackman. They separated in 2016. She now runs a private foundation and sits on the board of Friends of the High Line, the group that looks after the elevated park on Manhattan’s West Side.
Table of Contents
Karen Herskovitz at a glance
| Fact | Detail |
|---|---|
| Name | Karen Ann Herskovitz, also known as Karen Ackman |
| Age | About 60; she was 28 when she married in July 1994 |
| Education | Vassar College; master’s in landscape architecture, Harvard Graduate School of Design, 1993 |
| Marriage | Bill Ackman, 1994; separated 2016; divorce complete by January 2019 |
| Children | Eloise, Lucy and Liza Ackman |
| Now | President of the Seymour Foundation; board member at Friends of the High Line |
| Net worth | Not known. Vanity Fair and Fortune have both reported that the divorce cost Ackman nine figures, but the terms were never made public |
From Vassar to Central Park
Herskovitz grew up in New York, where her father, Seymour, ran an import-export company and her mother, Marilyn, sold homes. She studied art at Vassar before moving on to Harvard’s design school.
Bill Ackman was at Harvard Business School when they met. At a 2015 tribute to his father, Larry, Ackman told the room how it happened, Bloomberg reported. A client of Larry’s had faxed over the phone number of a Harvard design student. Larry forwarded the fax to his son, and when he rang later to follow up, Bill already had a date with her. A couple of years on, Larry told him that if he didn’t propose soon, he would find a nice guy who would. “Dad’s a good negotiator,” Ackman said.
They married at the St Regis Hotel in New York on 10 July 1994, both aged 28. The New York Times announcement described her as a landscape architect at the Central Park Conservancy, which manages the park. A biography published by the couple’s foundation says she “focused her career on public work”, designing for the conservancy and for two design firms, Robert A.M. Stern Architects and Judith Heintz Landscape Architecture.
The Pershing Square years
In 2006, two years after Ackman started his hedge fund, the couple set up the Pershing Square Foundation. By 2011 the two of them were its only trustees, and the Chronicle of Philanthropy reported that they planned to give away most of their wealth. They made that promise public in April 2012, when they signed the Giving Pledge.
Human Rights Watch added her to its board in 2009. The same Chronicle article described her as “perhaps more intimately involved with human-rights issues than her husband”, and in 2012 the couple pledged $10m to the group, spread over five years. Bloomberg, reporting the gift, said she also sat on its Africa and women’s rights advisory committees.
She was on the board of Friends of the High Line by 2011. When her mother died in 2015, the High Line’s trustees and staff placed a notice in the New York Times describing her as an “esteemed” board member. By 2017 she was also a trustee of Vassar.
The Chronicle also quoted her sister, Amy, who ran the foundation in its first years: “Karen is a more private person than Bill.”
The separation
On 22 December 2016 the couple emailed friends to say they were separating after 25 years together. “It is an amicable split, and we are making sure that we minimize the impact on our girls,” they wrote. The email was signed “Love, Karen and Bill.”
Page Six, which published the email, spent the following months working out what the divorce might cost him. When it returned to the story in March 2017, it noted that Herskovitz “didn’t get back to us”.
By the time Ackman married the designer Neri Oxman in January 2019, the divorce was complete.
The Seymour Foundation
Herskovitz went back to her maiden name and, in October 2018, set up a private foundation with $50,000 of her own money. The Seymour Foundation shares her late father’s first name, and she is its president.
In 2019 Ackman gave it about $30m in cash and shares, its tax returns show. Every gift recorded since then has come from Herskovitz, mostly in shares.
The Seymour Foundation in numbers
| Year | Gifts received | Grants paid |
|---|---|---|
| 2018 | $50,000 from Herskovitz | None |
| 2019 | $30.05m from Ackman; $100,748 from Herskovitz | $1.23m |
| 2020 | None | $1.48m |
| 2021 | $62,956 from Herskovitz | $2.01m |
| 2022 | None | $1.96m |
| 2023 | $175,376 from Herskovitz | $920,000 |
| 2024 | $409,581 from Herskovitz | $1.85m |
From the foundation’s annual returns. Its assets were worth about $28.9m at the end of 2024.
Only the returns for 2022 to 2024 list who received the money. The largest grants in those years went to:
- Friends of the High Line, where she sits on the board: $1.33m, including $1.11m in 2022
- The ACLU Foundation, the civil liberties group: $1.13m, including $1m in 2024
- Planned Parenthood of Greater New York: $410,000
- Peer Health Exchange, a youth health charity: $400,000
- Human Rights Watch, whose board she joined in 2009: $350,000
- Dalton, a private school in Manhattan: $205,000
Lucy’s recovery
Ackman has posted about Lucy’s recovery several times since August, most recently this month. His first post also announced that he and Oxman were giving about $400m in Pershing Square shares to a new brain research institute in Manhattan, a gift Fortune reported the next day. In that post he wrote:
“Lucy’s challenge has brought together our entire modern family who have all been incredibly devoted to her care and recovery.”
In September he shared a case report from her doctors on an experimental treatment for her eyesight. Its acknowledgements open by thanking “Bill Ackman, Karen Herskovitz and Lucy Ackman for their support and their commitment to advancing scientific discovery.”
