The Anti-Injunction Act: The Supreme Court ruled that since the Affordable Care Act named the tax penalty for failing to maintain minimum coverage a "penalty" instead of a "tax," the penalty didn't meet the requirements for protection under the Anti-Injunction Act.
The Minimum Coverage Provision: Further, justices said that while the individual insurance mandate doesn't fall under the Commerce Clause, it does fall under the Taxing Clause. Because Congress has the authority to tax citizens, the court said that the mandate can be interpreted as a tax. This brought the provision under the constitutional authority of Congress.
Severability: Justices didn't discuss whether the mandate could be severed from the rest of the legislation because they upheld the minimum coverage provision.
The Expansion of Medicaid: The court ruled Congress has the authority to expand Medicaid to people within 138 percent of the poverty line, but they cannot threaten to take away all Medicaid funding for states that don't want to expand their programs.