Grede Foundries Inc. has exited Chapter 11 bankruptcy protection with the completion of a merger with Citation Corp.

The new entity, Grede Holdings LLC, will be led by Doug Grimm, Citation's chief executive officer

The merger actually involved three transactions, Grimm said in an interview Monday. The first involved two groups—Wayzata Investment Partners LLC, Grede's outside investors; and GSC Group, Citation's outside investors—becoming majority shareholders; at the same time, the bankruptcy court conducted the sale of a vast majority of Grede's assets; and finally, the two companies combined.

All of Citation's assets are part of the merger and all of Grede's assets—except for the Greenwood, S.C., plant closed in October and the Vassar, Mich., plant sold separately in December—are part of...