system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5:US Supreme Court: King v. Burwell. Obamacare subsidies

In light of the recent ruling on King v. Burwell (in favor of the Government, 6-3) and the number of questions it's already creating we decided to make this sticky thread.  Feel free to ask any questions related to this ruling in this post or offer an explanation of the ruling and the background behind it.
gpt
"Obamacare" made health insurance exchanges. Each state had the option of making their own exchange, or using the federal exchange.

The part of the law in question gives federal money to people who are within 100% to 400% of the federal poverty line.

However, the law technically says the federal money can go to people who buy insurance from an exchange created "by the state" not "by the state, or by the federal government."

In the background of all of this, there is the fact that WAY more states refused to make their own exchanges, and used the federal exchange than Congress expected, because of negative reaction to the law.

So there are LOTS of people who got the federal money for insurance bought on the federal exchange. 

If the "by the state" language meant just "by the state" the whole insurance scheme would fall apart, because there are so many people who rely on the subsidies and the federal exchanges.

However, the Supreme Court just decided that "by the state" actually meant "by the state or the federal government," essentially because the law would not work without that interpretation.

So people get to keep their federal subsidies now, regardless of whether they bought their insurance on the federal or state exchanges.