CNN provides an easy to understand primer on what's at stake this time around. Find the article, "The latest Obamacare challenge: What you need to know" here.
The article explains that the law establishes the creation of exchanges "through which individuals can purchase competitively priced health insurance". Sixteen states and the District of Columbia have set up their own exchanges. Folks living in the other 34 states must use the exchange run by the federal government. And the law provides federal tax credits to income eligible individuals "to help offset the cost of the policies".
Most of us remember all of this. States set up their exchanges where you shop for your healthcare coverage. Lots of governors or state legislatures chose not to create their own exchanges, so their citizens go to the exchange run by the federal government. And because everyone is supposed to sign up if they don't have coverage elsewhere, the Affordable Care Act provided federal tax credits to help lower income individuals and families buy coverage.
Simple enough. Except, those bringing the case that is now before the Supreme Court say the law did not authorize those tax credits for those having to use the federal run exchange. That's where the four words in the law passed by Congress comes in.
A synopsis from the CNN article:
So this time around the law in its entirety is not at stake. But apparently the help through tax credits for 5 million individuals is at stake. (CNN reports that in 2014, more than 5.3 million individuals selected an insurance plan through the federal exchange.) We'll find out if Congress goofed or not.
Here is how CNN explains it:
Those challenging the law this time say: Congress limited the subsidies in order to encourage the states to set up their own exchanges. But when only a few states acted, the IRS tried to "fix" the law and wrote a rule allowing subsidies for those living in states with state-run exchanges as well as states with federally run exchanges.