Bill Ackman Rules Out a US Stock Bubble, Blames Leveraged Bets for Wild Swings

Bill Ackman says he sees no bubble in US stock prices. His worry is short-term trading on borrowed money, which he told CNBC on Tuesday has revived “casino-type” markets.

Ackman said the wild price swings this creates are bad for the country but good for Pershing Square, which uses them to buy stocks cheaply.

What Ackman Says Is Inflating the Stock Market

He named leverage, or borrowed money that multiplies gains and losses, and one-day options, bets on a stock’s same-day close.

BILL ACKMAN: STOCK MARKET IS "BROKEN" BY SPECULATIVE TRADINGPershing Square founder Bill Ackman warns that excessive leverage and speculation are driving irrational stock-price swings.Ackman compared today's trading environment to casino-style markets, criticizing leveraged…

— *Walter Bloomberg (@DeItaone) November 3, 2026

He also cited sports betting and perpetual futures, contracts with no end date.

“We’re back to the casino-type markets when there was 95% leverage,” he said.

Those swings let Pershing buy Microsoft in this year’s software sell-off and Amazon after its tariff slump.

Why Ackman Keeps Buying

Pershing says excitement over AI infrastructure firms has pulled attention from other businesses with lasting earnings growth, leaving them cheap.

The firm expects its holdings to grow earnings about 20% a year over the next three to five years, against 13% for the S&P 500.

Ackman called Visa and Mastercard two of the world’s greatest businesses. Pershing added both in the second quarter alongside Netflix, and began building an eighth new 2026 position after the third quarter.

Why He Rejects the Roaring 1920s Comparison

Ackman was asked about an Elliott Investment Management letter that, the Wall Street Journal reported, likens today to the boom before the Great Depression.

Elliott flagged debt-funded spending, public backlash against AI, and circular AI deals, where chipmakers invest in AI firms that then buy their chips.

“I don’t see a Roaring 20s in the stock market,” he added.

He said profit forecasts rose sharply this year and stock prices look reasonable against that growth. On the backlash, he said the US is in a global race for superintelligence and cannot slow down.

Private startup funding, he said, shows more bubble-like buying. Even so, he said corporate card startup Ramp justifies its valuation and that American Express should be concerned. Ramp was valued at $44 billion in June, according to the company.

Pershing’s next 13F, the holdings report big funds file with US regulators, is due by mid-November and will show its positions as of Sept. 30.