At $25 billion, Bill Ackman’s Pershing Square USA would have been the largest closed-end fund in the US|Senate Democrats|CC BY 2.0

Billionaire hedge fund manager Bill Ackman has delayed the initial public offering of his investment fund Pershing Square USA, according to the NYSE. The IPO was scheduled for next week.

The decision comes after a substantial reduction in the size of its anticipated share sale, from a staggering $25 billion to a more modest range of between $2.5 billion and $4 billion. 

At $25 billion, Pershing Square USA would have been the largest closed-end fund in the US.