Ackman Scales Back Multibillion-Dollar I.P.O.

The billionaire investor William Ackman appears to have scaled back his ambitions for an initial public offering in New York — at least in terms of its size.

The investment vehicle that Mr. Ackman plans to take public on the New York Stock Exchange next week — Pershing Square USA — is aiming to raise $2 billion in the share sale, according to a regulatory filing on Tuesday.

That’s a far cry from the $10 billion or more that Mr. Ackman discussed as a target earlier this year. In investor meetings in recent months, he had floated an even larger number: $25 billion.

The $2 billion figure is a place holder, and Pershing Square USA could raise more as investors put in orders through Monday night, according to a person familiar with the deal who spoke on the condition of anonymity because the details were private.

Mr. Ackman is now scheduled to ring the famed N.Y.S.E. bell the following Tuesday morning before trading in the stock kicks off, according to the person. But timing, the person said, could still slip.

It has been a bumpy road to the public market for Mr. Ackman and Pershing Square USA. Trading in the fund was originally scheduled for Tuesday morning but was postponed because the Security and Exchange Commission needed to review a letter Mr. Ackman had sent privately to some existing investors in his firm.