March 17 (Reuters) - Veteran investment banker Alan Mnuchin plans to raise $400 million for a blank-check firm through an initial public offering in the United States, regulatory filings on Wednesday showed. Falcon Capital Acquisition Corp II, a special purpose acquisition company, or SPAC, will sell 40 million units, consisting of shares and warrants, on the Nasdaq Capital Market, priced at $10 per unit. Mnuchin, brother of former U.S. Treasury Secretary Steve Mnuchin, is a former vice president of Goldman Sachs and the founder of New York-based investment bank AGM Partners LLC. The first SPAC, Falcon Capital Acquisition Corp, took digital health startup Sharecare Inc public in a $3.9 billion deal last month. SPACs are shell companies that raise equity to take a private company public through a merger at a later date, allowing such companies to sidestep a traditional IPO to enter public markets. Goldman Sachs & Co LLC is the lead underwriter for the offering. (Reporting by Sohini Podder in Bengaluru; Editing by Sriraj Kalluvila)