So what happens now to patients and their families who have real grievances against HMOs? It's been a contentious issue in Congress for some time, and it's about to go back on the agenda.
Bonnie Cicio lost her husband, Carmine, to myeloma, a form of blood cancer, six years ago.
"He was just a great guy," says Bonnie Cicio.
Cicio's doctor recommended a double stem cell transplant, calling it his "best chance" of survival. After a two month wait, his HMO would only agree to a single transplant — and by then it was too late. Carmine Cicio died a few weeks later.
Last year his widow, in an interview with NBC News, said she had no doubt why he died.
"I think it was the HMO’s denial and the length of time it took them,” she said.
She went on to file a $200 million wrongful-death lawsuit against the HMO. But legal experts say Monday’s U.S. Supreme Court decision effectively ends her lawsuit and all state court suits alleging malpractice against HMOs.
"It severely limits, it really eliminates meaningful remedies for severely injured people,” says Sarah Lock, an attorney for AARP.
Alleged victims can still sue in federal court, but can only recover the value of the procedure the HMO denied. In Bonnie Cicio's case, that would be the cost of a stem cell transplant, a fraction of what she believes the HMO should pay.
With legal remedies for HMO malpractice now all but eliminated Monday, in Congress some HMO critics said the Supreme Court's decision is just what they need to re-invigorate the patients rights movement.
Congressman John Dingell, D-Mich., says he'll reintroduce the patient’s bill of rights this week.
"The patients and the doctors will make the decision on health care not a bunch of cold-hearted HMOs," says Dingell.
If the bill becomes law, it would also assure that people like Bonnie Cicio have the right to sue their HMOs for malpractice.