Which Supreme Court ruling declared that the requirement to purchase health insurance under the Affordable Care Act was constitutional?

The Supreme Court ruling that declared the requirement to purchase health insurance under the Affordable Care Act was constitutional is indeed found in the case National Federation of Independent Business v. Sebelius. In this landmark decision, the Court upheld the individual mandate, which requires most Americans to have health insurance or pay a penalty. The ruling emphasized that while Congress does not have the power to compel individuals to buy a product under the Commerce Clause, it does hold taxing authority which allows it to impose a penalty for not purchasing health insurance. This constitutional interpretation of the Affordable Care Act was pivotal in affirming the law's core provisions, making it a significant decision in health care and commerce law.

The other cases listed address different aspects of the Affordable Care Act or related issues but do not pertain to the constitutionality of the individual mandate itself. They focus on issues such as government subsidies for insurance coverage and religious exemptions from coverage requirements, which were not the central issues of the mandate's legality.