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 a billionaire hedge fund manager, the founder, and CEO of Pershing Square Capital Management. Known as an activist investor, he leverages his position to influence company management and strategy. As of July 2025, his estimated net worth stands at $9.4 billion.

Sections (5)

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

2003: Feud with Carl Icahn

In 2003, a feud started between Ackman and Carl Icahn over an investment deal.

December 2012: Short Bet Against Herbalife

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

January 2013: Icahn Takes Stake in Herbalife

In January 2013, Carl Icahn announced a stake in Herbalife following a challenge to Ackman's comments on CNBC.

April 2014: FBI Probe into Herbalife

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

March 12, 2015: Federal Probe of Ackman's Actions

On March 12, 2015, reports surfaced that federal prosecutors and the FBI were investigating whether people hired by Ackman made false statements to encourage investigations and lower Herbalife's stock. Neither Ackman nor Pershing Square were subpoenaed.

April 27, 2016: Testimony Before Senate Committee

On April 27, 2016, Ackman testified before the United States Senate Special Committee on Aging about Valeant Pharmaceuticals' business model and pricing practices.

July 2016: Herbalife Settles with 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 a pyramid scheme. The FTC found Herbalife deceived consumers.

2019: Herbalife Pays SEC Settlement

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

March 18, 2020: Ackman Calls for Economic Shutdown

On March 18, 2020, Ackman publicly called for a "30-day shutdown" of the American economy to combat the spread of coronavirus, warning of severe economic consequences if action wasn't taken.

2020: Herbalife Pays DOJ and SEC Penalties

In 2020, Herbalife paid over $122 million after the Department of Justice and SEC found it falsified books and records and provided corrupt payments to Chinese government officials.

March 1, 2022: Remarks About Sabatini's Treatment

On March 1, 2022, Bill Ackman delivered remarks at a Pershing Square Foundation event regarding what he described as the unfair treatment of David M. Sabatini, a biologist accused of sexual misconduct.

2022: Herbalife Settles RICO Case

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

October 8, 2023: Demand for Names of Harvard Students

On October 8, 2023, Bill Ackman demanded the publication of the names of Harvard students who signed a letter condemning Israeli actions, stating he wanted to ensure his company and others would not inadvertently hire them.

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

In November 2023, Bill Ackman supported Elon Musk's response to antisemitic remarks and launched 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, expressing concerns about the safety of recently approved vaccines.

January 3, 2024: Business Insider Expose and Plagiarism Review Pledge

On January 3, 2024, Business Insider published an article detailing how Ackman's wife, Neri Oxman, plagiarized portions of her dissertation, prompting Ackman to pledge a plagiarism review of all MIT faculty.

January 2024: Calls for Resignations After Gay's Resignation

In January 2024, after Claudine Gay's resignation, Bill Ackman called for the resignation of Harvard Board Chair Penny Pritzker and other board members, citing diversity, equity, and inclusion movement as the cause of antisemitism and racism against white people at Harvard.

April 2024: Video Call Regarding Columbia Protests

In April 2024, Bill Ackman was part of a WhatsApp group chat that held a video call with New York City Mayor Eric Adams, reportedly to pressure Columbia's president to allow police to shut down campus protests.

May 16, 2024: Involvement in WhatsApp Group Chat

On May 16, 2024, it was reported by The Washington Post that Bill Ackman was involved 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 by conveying "the atrocities committed by Hamas" and "help [Israel] win the war" on U.S. public opinion following U.S. protests against the Gaza war.

2024: Ackman Endorses Trump

In 2024, long-time Democratic donor Ackman endorsed Donald Trump in the United States presidential election. He also actively supported Israel, criticized pro-Palestinian protests, and called for Claudine Gay's resignation as Harvard's president.

May 18, 2025: Defense of Trump's Defunding of Harvard

On May 18, 2025, Bill Ackman defended President Trump's defunding of science research at Harvard, citing antisemitism on campus, and claimed student protesters coordinated with Hamas.

June 14, 2025: Advocating for US to Join Israel's War Against Iran

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

2025: Participation in Hall of Fame Open and Declined Endowment

In 2025, Bill Ackman received a wild card berth at the Hall of Fame Open at the age of 59, where he lost in a doubles match. Following criticism, Ackman offered a $10 million endowment to the International Tennis Hall of Fame, which declined the offer.