(CNN) -- A key provision of the health care reform law championed by President Barack Obama came under harsh criticism from the conservative majority of the Supreme Court on Tuesday. The justices debated a hotly contested issue testing the limits of government-mandated contraception coverage, specifically involving for-profit corporations that object to it for religious reasons. The justices appeared divided along ideological lines in a 90-minute oral argument, with the federal government offering a spirited defense of the Affordable Care Act. "How does a corporation exercise religion?" asked Justice Sonia Sotomayor, summarizing perhaps the key constitutional question at hand. "This is a religious question," said Justice Samuel Alito, suggesting the businesses have such a right. "You want us to provide a definitive secular answer."
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Justices appear divided along ideological lines in oral argument
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Hobby Lobby, Conestoga Wood Specialties say they run their firms with Christian values
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Obamacare's contraception coverage requirements violate those values, they say
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Requirements apply to the corporations, not the individual owners, the government says
The Hobby Lobby and Conestoga claims are in yet another @placeholder category: for-profit corporations claiming a religion-based exemption.