The two companies settled billing disputes between doctors and insurers, keeping patients out of the middle. One let doctors win 96 percent of the time.

In our series “The Cost of Denial,” NBC News’ Maggie Vespa reports on a 13-year-old Illinois girl who suffers from as many as four seizures a day. Insurance denied coverage for the surgery her doctor said could help, but then reversed its decision days after we asked about the case.