I’ve always suspected that that incentivized health insurance companies to let hospitals inflate costs. If the government forbids me from increasing my percentage of the pie and I need to increase revenue I have to increase the size of the pie.
Yes, this and vertical integration. The insurance company may have limited profit, but if the hospital doesn't, and they're both owned by the same parent company, then the prices "inside the control volume" can be whatever fiction is most convenient to report to the government.
Looked up the largest health insurer, they operate hospitals:
> Kaiser Permanente operates 39 hospitals and more than 700 medical offices, with over 300,000 personnel, including more than 87,000 physicians and nurses.
