In NFIB v. Sebelius the Supreme Court upheld the constitutionality of all but one of the provisions of the Patient Protection and Affordable Care Act. The opinion of Chief Justice Roberts is the controlling opinion in all respects. This is an editted summary of the Chief Justice's opinion.
Huhn, Wilson, "Excerpts from Chief Justice Roberts' Opinion in NFIB v. Sebelius" (2012). Akron Law Faculty Publications. 91.