Doctors typically abandon surgery after 5 hours of brain compression, but she underwent surgery at 19 hours
Ackman describes how doctors typically declare brain death and abandon surgery after more than 5 hours of bleeding-induced compression, while his daughter was compressed for 19 hours before undergoing surgery at his insistence; today her cognition and sense of humor have largely recovered, though language, vision, and mobility remain in difficult recovery.
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Doctors abandon surgery after 5 hours of brain compression
Lucy had a congenital arteriovenous malformation (AVM), where arteries connected directly to veins without the usual capillary buffer, causing dangerously high pressure that ruptured vessels and caused brain bleeding. The bleeding compressed her brainstem, affecting breathing and heartbeat. Based on when she collapsed, doctors estimated she'd been compressed for 19 hours—well beyond the 5-hour threshold at which physicians typically declare brain death and stop operating. She'd been missing for two hours before she was found, then faced additional delays for transfer and CT scanning. Doctors told the family they couldn't predict what disabilities she'd face, but Ackman insisted they make the attempt. Surgeons removed approximately 40% of her skull to relieve the pressure and complete the operation.
— Bill AckmanHe built a neuroscience institute from a family medical catastrophe
Three months after Lucy's crisis, Ackman purchased a vacant biotech building at 65th Street and 11th Avenue, ten blocks from his office, completing the deal in 60 days. He then contracted to acquire another 3.4 acres adjacent to it. His goal is to build the world's best neuroscience institute, focused on brain rehabilitation, recovery, and longevity. Ackman notes that the crisis intersected perfectly with his background: he's a real-estate investor able to acquire buildings at low prices; his wife is an architect able to design rehabilitation spaces. The need is clear: most brain-hemorrhage patients can't undergo surgery at all, and those who do are often transferred to nursing homes, where they die from pneumonia within months.
— Bill AckmanNine years of employee retention became the foundation for absolute trust
The hedge-fund industry norm involves top talent jumping between firms every few years for signing bonuses reaching into the millions. Ackman's Pershing Square team has had virtually zero turnover for nine years, with only a few junior additions. He argues that frequent job-switching makes it impossible to know whether colleagues are hiding risks from you. But nine years of continuity built a foundation of trust that means he never doubts anything his team tells him. This institutional stability has also allowed him to evolve from being involved in every decision to contributing only a handful of investment ideas while focusing on strategy.
— Bill AckmanVC valuations doubled in two weeks—a classic bubble signal
Ackman described a stark example of VC bubble dynamics: he met a company that wasn't planning to fundraise. Within two days, investors were rushing to invest $50 million at a $400 million valuation. Then, two weeks later, the same company raised another $50 million at a $5 billion valuation. He sees the same FOMO-driven behavior throughout the venture market—comparable to the mindset during the internet bubble when capital seemed infinite. His warning to founders: this is a good time to raise, but don't spend as if the money will flow forever. Eventually a high-profile company will crash, the market will reprice, and only those who treated every dollar as their own money and preserved a long runway will survive.
— Bill AckmanEven Buffett missed the internet; now everyone faces AI disruption
Ackman argues that evaluating disruption risk is central to sound investing, and AI has sharply raised that bar. Even Warren Buffett, arguably history's greatest investor, failed to anticipate how the internet would render entire categories obsolete—for example, Wikipedia displaced the World Book encyclopedia. The problem is now more complex. On the positive side, AI offers genuine value: Cognition's systems can rewrite legacy COBOL code that accumulated in large financial institutions over decades of mergers, condensing work that would normally take months into days and substantially lowering operational costs. But the paradox is insoluble: no one can guarantee that a company you invest in—no matter how wide its moat appears—won't suddenly face disruption from an AI breakthrough.
— Bill AckmanMassive losses taught him to carve investment principles into stone
Between 2015 and 2016, Pershing Square suffered major losses. Afterward, Ackman decided to codify his investment principles and keep them visible: invest only in simple, predictable, large-cap businesses that generate free cash flow, and avoid short-selling. His aversion to shorting runs deep. Going short is asymmetrically unfavorable—losses can be unlimited while gains are capped. When his team shorted a pyramid-scheme fraud years earlier, they thought they held the moral high ground and would obviously win, but underestimated the dynamics of short squeezes and other market forces, leading to years of litigation and personal attacks in the media.
— Bill AckmanA real-estate empire's hidden ambition: become a modern insurance company
Howard Hughes—the real-estate company—originated as unwanted assets spun out during the General Growth bankruptcy restructuring. It owned large master-planned communities (MPCs). For 14 years, Wall Street dismissed this real-estate development business, but Ackman transformed it into a modern analogue of Berkshire Hathaway: he acquired Vantage, a property-and-casualty reinsurance company, hired the industry's best underwriting team, and redirects the float—the funds collected in premiums before claims are paid—into long-term equity investing. The company's capital structure is currently roughly 70% real estate and 30% insurance. His five-year goal is to flip those ratios to 70-75% insurance.
— Bill AckmanA decade of fallout from short-selling still shapes his choices
Ackman acknowledges that his reputation suffered durably from his short-seller label, particularly the Herbalife position that began in late 2012. Many ordinary people view shorting itself as inherently unethical. Going long wins you allies; going short makes you an existential threat to the target company, which mobilizes all its resources against you—and can unite the hedge-fund industry to squeeze you out. The Herbalife campaign took its toll. Over a decade later, Ackman emphasizes (whether you believe him or not), they've done zero activist short positions since 2016. He now prefers to build influence through long-term equity stakes and patient capital, moving opponents through private persuasion rather than public confrontation.
— Bill AckmanIn their own words · checked verbatim
And what you need to do is you need to release the pressure on the brain as quickly as possible. And the way you do that is you remove about 40% of the skull to allow the brain to expand beyond the skull.
Bill Ackman3:10
I didn't learn actually until weeks later, they don't normally do the surgery to save someone when it's been more than five hours because the assumption is brain death, basically.
Bill Ackman4:11
I have this view that you, every bad thing, something good comes from it.
Bill Ackman9:19
When you've built a relationship with people and you work with them for nine years and you have this culture of transparency and candidness, I don't for a second ever question anything that's being told to me by a member of the investment team.
Bill Ackman18:33
Met with a company, let's say two weeks ago, and they weren't raising money. Two days later, they close around. They were preempted by some investor who put $50 million in a $400 million valuation. And then two weeks later, they raised another $50 million at a billion dollar valuation.
Bill Ackman24:43
All of us are guaranteed to look foolish with one business or another that we didn't anticipate the risk of disruption because of AI.
Bill Ackman30:55
we've got to take our investment principles and literally engrave them on a stone tablet and put them on our desk.
Bill Ackman39:06
you make an investment in a company and then you learn new information that's inconsistent with the original thesis. You either have to buy a lot more because the stock's gotten cheap and you believe that the new information is not material or you have to exit because the thesis is broken.
Bill Ackman51:37
Figures
| Skull removal during surgery | approximately 40% | 3:10 |
| Duration of Lucy's brain compression | 19 hours | 4:11 |
| First VC valuation in two-week example | $400 million | 24:43 |
| Second VC valuation in two-week example | $5 billion | 25:43 |
| Ackman's stake in Pershing Square GP | approximately 45% | 20:35 |
| Pershing Square's stake in Howard Hughes | 47% | 56:41 |
| Howard Hughes Hawaii development contract | $4 billion | 59:46 |
Glossary
- AVM (arterial-venous malformation)
- Brain condition where arteries connect directly to veins, bypassing capillaries, causing venous pressure to surge and vessels to rupture.
- MPC (master-planned community)
- Large residential development where a single developer owns and long-term controls all land and planning, functioning as a self-contained city.
- Float (insurance)
- Premiums collected by insurers that sit briefly before claims are paid out, available for the insurer to invest for returns.
How to listen
Investors and founders interested in how family medical crises force resource allocation, VC bubble signals, and how value investors navigate AI disruption risk.
From 1:06:28 onward, anecdotes about acquiring the watchmaker Bremont are tangential with low information density; skip if short on time.