In another ruling that surprised some observers, the U.S. Supreme Court upheld the Patient Protection and Affordable Care Act, the sweeping health care reform law passed by Congress and signed by President Obama in 2010.

The decision was made on a 5-4 vote, with Chief Justice John Roberts writing the majority opinion (PDF). He was joined by associate justices Stephen Breyer, Ruth Bader Ginsburg, Sonia Sotomayor and Elena Kagan. Associate justice Anthony Kennedy wrote in a dissenting opinion that the entire law should be struck down. Joining him in the dissent were associate justices Antonin Scalia, Samuel Alito and Clarence Thomas.

The law has many provisions. Here are the basics, according to Wikipedia:

PPACA requires individuals not covered by employer- or government-sponsored insurance plans to maintain minimal essential health insurance coverage or pay a penalty unless exempted for religious beliefs or financial hardship, a provision commonly referred to as the individual mandate. The Act also reforms certain aspects of the private health insurance industry and public health insurance programs, increases insurance coverage of pre-existing conditions, expands access to insurance to 30 million Americans, and increases projected national medical spending (whilst reducing the deficit and slowing health inflation) while lowering projected Medicare spending.

The provision of the law that the most observers felt was vulnerable to being struck down was the individual mandate. However, the Roberts-led majority said that Congress was within its rights to impose the mandate:

“The Affordable Care Act’s requirement that certain individuals pay a financial penalty for not obtaining health insurance may reasonably be characterized as a tax. Because the Constitution permits such a tax, it is not our role to forbid it, or to pass upon its wisdom or fairness.”

However, the decision did not come without its caveats. The court ruled that the federal government may not penalize states for not complying with the PPACA’s expansion of Medicaid.

In May, we published an article that outlines how small businesses are likely to be affected by the health care reform law as it is implemented in phases. You can read it here.