Bill Ackman's new fund said Tuesday it was aiming to raise up to $2 billion in its initial public offering in the United States, drastically lower than its first target that would have ranked among the biggest IPOs ever.

Pershing Square USA will look to sell up to 40 million shares priced at $50 each. It was initially expected to bring in as much as $25 billion in new capital, but Ackman last week said the fundraise would be capped at $10 billion.

Ackman, a prolific investor with a vast social media following, is one of the most public faces in the hedge fund industry. He often uses his account on X to weigh on topics ranging from political battles to higher education.

Earlier this year, he led a campaign criticizing Harvard University after turmoil over practices related to antisemitism, plagiarism and financial management.

He was also backing on his popularity among retail investors to support the fund. But potential shareholders expressed some concerns about its structure, how quickly the cash would be invested and who would do the investing.

The fund has said it will acquire and hold positions in 12 to 15 large capitalization, investment grade, free-cash-flow-generative undervalued companies in North America.

It is aiming for a listing on the New York Stock Exchange under the symbol "PSUS."