42 U.S. Code § 18115 - Freedom not to participate in Federal health insurance programs
No individual, company, business, nonprofit entity, or health insurance issuer offering group or individual health insurance coverage shall be required to participate in any Federal health insurance program created under this Act (or any amendments made by this Act), or in any Federal health insurance program expanded by this Act (or any such amendments), and there shall be no penalty or fine imposed upon any such issuer for choosing not to participate in such programs.Please do your own research.
The above is from The Cornell University Law School Website:
http://www.law.cornell.edu/uscode/text/42/18115