U.S. District Judge Timothy Black has approved a previously disclosed $179 million settlement and entered a final judgment in a dispute between AK Steel and retirees at its Butler, Pa., steel plant.

The AK Steel retirees had filed a class-action lawsuit in June 2009 to stop the company from making changes to their health insurance benefits. It had started making retirees pay a portion of their premiums in January 2010.

West Chester-based AK Steel is the largest Dayton-area company, with more than $4 billion in revenue.

Under the terms of the settlement, AK Steel will continue to pay for the benefits through 2014 and also pay $91 million to two trusts to cover future benefits for hourly and salaries retirees.

In return, the company has been relieved of liability for any benefits after 2014, and the lawsuit was dismissed.