A glitch hidden in one of Obamacare’s 10,000 pages of rules could increase some families’ health insurance costs by thousands of dollars  and leave children uncovered.

To qualify as “affordable” under the federal health care law, employer-provided health insurance must cost no more than 9.5 percent of the employee’s salary. Otherwise, the individual is eligible to receive subsidies for the purchase of health insurance through the Obamacare exchanges instead.

But this measure applies only to individual employees, not families. The result will be a drastic cost increase in cases where affordable employer-provided insurance doesn’t cover the whole family.

Though this is raising tensions a week before the Obamacare exchanges’ launch date, the problem is not new. Two years ago, The Daily Caller reported on a National Bureau of Economic Research study revealing that the government had restricted subsidy calculations to include just the employed individual, not all family members potentially covered by an insurance plan. (RELATED: Researchers: Obamacare cost estimates hide up to $50 billion per year)

Former President Bill Clinton raised the problem in a recent speech and called the increasing family cost an “unintended consequence,” but the change was deliberate.

The problem appears to stem from the Joint Committee on Taxation’s 2010 decision to change language referring to “individual or family coverage” to “self-only” insurance instead.

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