The U.S. Treasury Department, chair of the Committee on Foreign Investment in the United States ("CFIUS"), recently published guidance on the types of transactions previously reviewed by CFIUS that have presented national security considerations ("Guidance").  The Guidance is intended to provide insight into how CFIUS identifies the national security effects of covered transactions and may assist parties considering whether to file a voluntary notice of a transaction with CFIUS [1]. This is an important determination because, although filing a CFIUS notice is voluntary, the parties may be forced to unwind a transaction where no filing was made if the President later determines it poses national security risks.