The US law that extends health insurance coverage to most Americans, dubbed "Obamacare" by its detractors, is 2,400 pages long, but only a few points have been challenged before the US Supreme Court.
-- THE INDIVIDUAL MANDATE --
Beginning in 2014, every US citizen will be obliged to acquire health insurance, either individually or through their employer, or be subject to sanctions. The only exceptions are members of certain faiths, prisoners, elderly or disabled Americans covered by Medicare, and those covered by Medicaid, the insurance program for the poor.
It is the most controversial element of the law, which is challenged by 28 states. Opponents argue that Congress overstepped its constitutional prerogatives requiring individuals to buy insurance. The administration contends that the Congress was on solid ground by virtue of constitutional provisions on trade and taxes.
-- PRE-EXISTING CONDITIONS --
Beginning in 2014, insurance companies must extend coverage to all applicants regardless of pre-existing health conditions.
This point has not been challenged, but it may not survive if the individual mandate is judged unconstitutional. The Supreme Court will have to determine whether the law could survive without this key measure.
-- COVERAGE OF THE POOR --
The income levels for those eligible for coverage under Medicaid, the government insurance program for the poor, are raised to 133 percent of the poverty level, extending the benefit to 16 million Americans.
The states appealing to the court say this reform would involve a notable transformation of the federal-state partnership in the financing of Medicaid. The administration assures that the additional cost will be financed entirely by the federal government.
-- THE MARKETS --
Each state is to create a marketplace by 2014 where individuals and employers can compare insurance policies and rates and sign up for coverage. Some part of the population and small businesses could be eligible for government assistance. Businesses with more than 50 employees who do not offer their employees coverage by 2014 must pay a fine.