PPM.net can assist with your Reg S and 144A offerings.
Question: If US issuer and I’m a foreign investor, which rule should I focus?
Regulation S – Bonds sold under Regulation S may not be offered, sold or delivered within the United States or to, or for the acount or benefit of, U.S. persons, except pursuant to an exemption from, or in a transaction not subject to, the registration requirements of the Securities Act.
Reg S and 144A Bonds are generally assigned two separate sets of securities identification codes. Typically, Reg S bonds get a common code and an International Securities Identification Number (“ISIN”) and are generally accepted for clearance through the Clearstream, Luxembourg and and other systems. 144A bonds get a CUSIP number and an “ISIN” and are generally accepted for clearance through the DTC system.
144A is a private placement in the US for US investors
RegS is a Bond issued in the Eurobond market for international investors
Note that after the initial period both series are normally merged mainly in an effort to increase the liquidity of such bonds.