Industrial Opportunity Partners LLC acquired Combined Locks, Wis.-headquartered paper mill Midwest Recycled and Coated Containerboard Mill LLC, also known as Midwest Paper Group.

Dave Mackin, an operating principal at the private equity firm, will join Midwest Paper as chairman.

The transaction marks the fourth investment for the Industrial Opportunity Partners III LP fund.

JP Morgan Chase Bank and Chemical Bank provided senior debt financing for the deal, while Yukon Partners provided subordinated debt financing. McDermott Will & Emery LLP represented the firm in the transaction.