Tucked onto page 737 of the law, enacted on March 23, 2010, is a provision that was supposed to eliminate that kind of dunning and overbilling. Section 9007 of the Affordable Care Act instructs the Internal Revenue Service to take away the tax exemption for nonprofit hospitals like Yale–New Haven unless they become aggressive about informing patients clearly of the availability of financial aid and take steps to learn whether patients need such assistance before they hand over their bills to lawyers or debt collectors.

More important for Gilbert and hundreds of thousands of patients like her, Section 9007 says the IRS can now take away a hospital’s tax exemption if it tries to charge patients who needed financial aid more than the average amount paid for services by insurance companies and Medicare. In other words, hospitals cannot try to make people like Gilbert pay the inflated chargemaster prices.

That’s a big deal. And it’s been black-letter law for more than 3½ years.

So how can it be that, two months ago, Jeremy Kopylec, a warehouse worker who lives in Northford, Conn., was sued by Yale–New Haven Hospital for $6,129? The suit, filed on Oct. 3, has to do with the bill Kopylec incurred four years earlier, when he was taken to the emergency room after what he says was a “minor motorcycle accident.”