Most Talked-About Controversies Linked to Bill Ackman

Controversies are a part of history. Explore the biggest scandals linked to Bill Ackman.

Bill Ackman is an American billionaire hedge fund manager, the founder, and CEO of Pershing Square Capital Management. Known as an activist investor, Ackman's strategies often involve taking significant stakes in companies and then publicly advocating for changes in their management or business strategies. As of July 2025, his estimated net worth is $9.4 billion, highlighting his success and influence in the financial world.

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Full Timeline Early Life & Education Career & Achievements Challenges & Struggles Controversies & Scandals

2003: Feud with Carl Icahn

In 2003, a feud developed between Bill Ackman and Carl Icahn over an investment deal, leading to a lawsuit by Ackman for his share of profits in a stock sale.

December 2012: Short Bet Against Herbalife

In December 2012, Bill Ackman announced that Pershing Square had made a $1 billion short bet against Herbalife, a maker of weight-loss and vitamin supplements, and described the company as a "pyramid scheme".

2012: Shorting Herbalife

From 2012 to 2018, Bill Ackman held a US$1 billion short against Herbalife, describing the company as a pyramid scheme.

January 2013: Icahn's Stake in Herbalife

In January 2013, Carl Icahn announced a stake in Herbalife to combat Ackman's short position, following a dispute between the two on CNBC.

April 2014: FBI Probes Herbalife

In April 2014, Reuters reported that the FBI conducted a probe into Herbalife and reviewed documents obtained from the company's former distributors following Bill Ackman's campaign.

March 12, 2015: Federal Probes into Herbalife and Ackman's Activities

On March 12, 2015, it was reported that federal prosecutors and the FBI were probing whether some people hired by Bill Ackman made false statements in an attempt to encourage investigations and lower Herbalife's stock. Bill Ackman stated he would not back down from his claims against Herbalife. Neither Ackman nor Pershing Square were subpoenaed.

April 27, 2016: Testimony Before Senate Committee on Aging

On April 27, 2016, Bill Ackman testified before the United States Senate Special Committee on Aging with Valeant Pharmaceuticals' outgoing CEO, J. Michael Pearson, and former interim CEO, Howard Schiller, regarding concerns about Valeant's business model and pricing practices.

July 2016: Herbalife Settles with the FTC

In July 2016, Herbalife settled with the Federal Trade Commission (FTC), agreeing to pay $200 million and restructure its business practices to avoid being labeled as a pyramid scheme. The FTC found that Herbalife "deceived consumers" and that "the small minority of distributors who do make a lot of money are compensated for recruiting new distributors."

2018: Shorting Herbalife

From 2012 to 2018, Bill Ackman held a US$1 billion short against Herbalife, describing the company as a pyramid scheme.

August 2019: Discouraging Ito from Mentioning Oxman

In August 2019, Bill Ackman wrote to MIT Media Lab director Joi Ito to discourage him from mentioning Neri Oxman when discussing Jeffrey Epstein.

2019: Herbalife Pays SEC for False Statements

In 2019, Herbalife paid the SEC $20 million to settle charges that it made false and misleading statements about its China business model.

2020: Herbalife Pays for Corrupt Practices in China

In 2020, Herbalife paid more than $122 million after the Department of Justice and SEC found Herbalife "falsif[ied] books and records and provide[d] corrupt payments and benefits to Chinese government officials for the purpose of obtaining, retaining, and increasing Herbalife's business in China."

March 1, 2022: Remarks on Sabatini's Treatment

On March 1, 2022, at a Pershing Square Foundation event, Bill Ackman delivered remarks about what he called David M. Sabatini's unfair treatment.

2022: Herbalife Settles RICO Violations Case

In 2022, Herbalife paid $12.5 million to settle a case of alleged RICO violations.

October 8, 2023: Demand for Publication of Student Names

On October 8, 2023, in response to a letter from Harvard student groups condemning Israeli actions, Bill Ackman demanded the publication of the names of all students involved so that he could ensure his company and others do not "inadvertently hire" any of the signatories.

November 2023: Support for Elon Musk and Campaign against Claudine Gay

In November 2023, Bill Ackman supported Elon Musk after he expressed support for antisemitic remarks. Ackman also engaged in a campaign to remove Claudine Gay from her position as Harvard's president.

2023: Support for RFK Jr's Stance on Vaccinations

In 2023, Bill Ackman declared support for RFK Jr's stance on vaccinations, stating he raised important issues about vaccines and their safety.

2023: Participation in WhatsApp group chat

In 2023, Bill Ackman was member of Whatsapp group which later held a video call in April 2024 with New York City Mayor Eric Adams.

January 3, 2024: Business Insider Expose on Neri Oxman's Dissertation

On January 3, 2024, Business Insider published an exposé detailing how Bill Ackman's wife, Neri Oxman, plagiarized portions of her dissertation.

January 2024: Calls for Resignation of Harvard Board Members

After Claudine Gay resigned in January 2024, Bill Ackman called for the resignation of Harvard Board Chair Penny Pritzker and other members of the board, describing the university's diversity, equity, and inclusion movement as the "root cause of antisemitism at Harvard".

April 2024: Video Call with NYC Mayor Eric Adams

In April 2024, members of the 2023–2024 WhatsApp group chat held a video call with New York City Mayor Eric Adams to pressure Columbia's president to permit the mayor to send police to shut down campus protests.

May 16, 2024: Involvement in WhatsApp Group Chat

On May 16, 2024, The Washington Post reported on Bill Ackman's involvement in a WhatsApp group chat with Israeli military leaders and top US business leaders with the stated goal to "change the narrative" in favor of Israel.

2024: Endorsement of Donald Trump and Support for Israel

In 2024, Bill Ackman endorsed Donald Trump in the United States presidential election, having been a long-time donor to Democratic candidates. Furthermore, Ackman has been an active supporter of Israel, especially following the October 7 attacks, and criticized the pro-Palestinian protests on university campuses in 2024.

May 18, 2025: Defense of Trump's Defunding of Science Research

On May 18, 2025, Bill Ackman defended President Trump's defunding of science research at Harvard on the grounds of antisemitism on campus during a panel at the Center for Jewish History.

June 14, 2025: Advocating for US to join Israel in War against Iran

On June 14, 2025, Bill Ackman posted a tweet on Twitter advocating for the US to join Israel in its war against Iran.

2025: False Identification in Brown University Shooting

After the 2025 Brown University shooting, Bill Ackman shared information falsely identifying a Palestinian Brown University undergraduate student as the shooter.

2025: Hall of Fame Open Appearance and Controversy

In 2025, Bill Ackman received a wild card berth at the Hall of Fame Open at the age of 59 and lost in a doubles match, leading to criticism and the rejection of a $10 million endowment offer to the International Tennis Hall of Fame.