Insurance companies returned over $1.5 billion in rebates to consumers between 2011 and 2012, according to a report issued on Tuesday. The reason is an ObamaCare requirement meant to force companies to spend a higher proportion of premiums on medical costs or quality improvements. The new law states that 80-85 percent of premiums must be used by companies to pay for treatment and medical costs. Companies that fail to meet that ratio must pay rebates. Critics of the provision, known as the medical loss ratio (MLR), have called it a price control mechanism that will push small and medium-sized insurance providers out of business.