TWG,
While there are many regulations about offering and selling securities to US citizens, foreign issuers can rely on the private placement exemptions to sell securities to US citizens. I don't think it would be any problem to qualify any transaction with a US corporation as a private placement. I'm speaking from a small amount of experience in this area a long time ago, but I don't believe anything has changed. Some entities do not need the protection afforded by a full out registration statement.