There was supposed to be a severability clause in the bill, but that was mistakenly left out of the bill. Thus, ObamaCare says nothing regarding severability. In that situation, courts presume the legislature intended severability.
That presumption is overcome if either (1) it is proven that the legislature intended the unconstitutional provision to be nonseverable or (2) the unconstitutional provision is seen as essential (the law can not reasonable function without it).
You've got to be kidding me. "Mistakenly" left out? All that hullabaloo about that health care bill and one of the most important parts of the bill they "mistakenly" left out?
I gotta bridge to sell anybody believes this. My guess is that they told all those concerned that the Supremes would overturn any mandate that the bill would allow the mandate to be severed and the health care system overhaul would still move forward.
Only somebody done went and "mistakenly" left it out, just doggone.