Few Wall Street investors are willing to rewrite the playbook that made them famous. Bill Ackman appears to be doing exactly that. For two decades, Ackman built a reputation as one of America’s most aggressive activist investors, taking large, concentrated positions in public companies and publicly pushing for change.
Now, the Pershing Square Capital Management founder is reshaping his firm around a slower, more patient philosophy modelled on Warren Buffett, the “Oracle of Omaha” whose Berkshire Hathaway became one of the most successful investment vehicles in history. The change in the approach is about structure, time horizon, and how money itself is managed. According to recent reports, Ackman is attempting something ambitious, building what he calls a “modern-day Berkshire.”
How is Ackman mirroring Buffett?
For much of his career, Ackman thrived on confrontation. Through Pershing Square Capital Management, he took large positions in companies and pushed for change, sometimes dramatically. His campaigns around Herbalife, Canadian Pacific, and Chipotle became defining moments of activist investing.
But activism has limits. It depends on timing, market sentiment, and, crucially, investor patience. As reported by CNBC, over the past year, Ackman has started moving away from this model toward something closer to Buffett’s philosophy, buy strong businesses and hold them for the long term.
“We think of our business model as akin to owning a royalty on the compounding of assets invested in high-return investment strategies.” as Ackman and has increasingly focused on companies like Universal Music Group, Hilton, and Tim Hortons, businesses that generate steady, recurring income with relatively low capital needs. As Acquirer’s Multiple notes, these are similar in spirit to Buffett’s classic bets like Coca-Cola or See’s Candies, companies that compound cash over decades. The difference is clear. Earlier, Ackman looked for change. Now, he is looking for durability.
Insurance business
Berkshire Hathaway’s insurance businesses generate “float” money that can be invested for long periods before claims are paid. This gave Buffett a powerful advantage that they are stable, long-term capital. Ackman does not have an insurance empire of that scale. So, he is trying to recreate the effect differently.
In March 2026, Pershing Square filed for a double IPO, as reported by CNBC and Bloomberg. The structure links a closed-end fund, Pershing Square USA Ltd., with the management company. Investors who buy into the fund also receive shares in the management company, aligning incentives toward long-term performance.
The goal is to lock in capital permanently. If successful, this would free Ackman from the pressure of redemptions and allow him to invest with a much longer horizon which is very close to Buffett’s “forever” mindset.
Building a mini Berkshire
Ackman’s ambitions go beyond portfolio strategy. He is also trying to build a conglomerate structure similar to Berkshire itself. It is speculated that his large and growing stake in Howard Hughes Holdings is central to this plan. Now owning nearly half the company and serving as executive chairman, Ackman is reshaping it from a real estate-focused business into a diversified holding company. According to AInvest, this includes acquiring operating businesses and even exploring insurance assets. This mirrors Buffett’s approach of using a core business to generate capital, then redeploy it into a wide range of investments.
But scale remains a key difference. Berkshire Hathaway operates with hundreds of billions in capital and can make massive acquisitions during market crises. Ackman’s platform, while significant, is still far smaller. That limits his ability to act as a buyer of last resort which is one of Buffett’s biggest advantages.
Risk, temperament, and track record
Buffett is known for caution, patience, and an almost obsessive focus on capital preservation. Ackman, by contrast, has built his reputation on bold, concentrated bets. His portfolio often holds just eight to ten positions, leading to both strong returns and sharp drawdowns. Pershing Square has delivered nearly 20 percent annualised returns since 2004, those gains have not come without volatility, as noted by Newsylist.
This raises an important question: can Ackman truly adopt Buffett’s discipline, or will his instinct for high-conviction bets remain?
There are also execution risks. Transforming a company like Howard Hughes into a Berkshire-style conglomerate requires exceptional capital allocation across industries, something Buffett refined over more than six decades. As CNBC reports, analysts warn that success will depend on balancing growth with careful risk management, especially if insurance becomes part of the model. Long-term wealth is built not just through smart investments, but through the right structure and patience.
By pursuing permanent capital, focusing on high-quality businesses, and moving from activism to ownership, he is laying the foundation for a more durable investment platform. As Fortune reports this is also about legacy, building something that can outlast him.
Still, Buffett’s success was shaped by unique conditions including decades of trust, access to cheap insurance float, and the ability to act decisively during market crises.
Ackman may have the blueprint, but the real test lies ahead. If he can combine his sharp instincts with Buffett-like discipline, Pershing Square could evolve into the first true “modern-day Berkshire.” If not, it will show that structure alone cannot replicate the genius of compounding over time.
Disclaimer: This article provides factual analysis only and is not, and should not be construed as, an offer, solicitation, or recommendation to buy or sell securities. Investors must conduct their own independent due diligence and seek advice from a registered financial advisor in the respective jurisdiction.