Obamacare, formally known as the Patient Protection and Affordable Care Act (PPACA), is a United States federal statute signed into law by President Barack Obama on March 23, 2010. The law is the principal health care reform legislation of the 111th United States Congress and is the signature legislation of the Obama presidency. PPACA requires individuals not covered by employer or government-sponsored insurance plans to carry 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 while lowering projected Medicare spending.

The individual mandate requiring people to have health insurance caused major controversy in the country as opponents challenged the law to be in violation of private citizens' constitutional rights. On June 28, 2012, the U.S. Supreme Court upheld Obamacare. In a 5-4 ruling, the high court decided the individual mandate requiring people to have health insurance is valid as a tax, even though it is impermissible under the Constitution's commerce clause.