Pullman-Peabody gave up its fight for Joy.

Pullman-Peabody Co. said it dropped its bid to buy Joy Manufacturing Co., which has agreed instead to be purchased by an investor group for $35 a share, or $620 million. Pittsburgh-based Joy is a maker of oil field and petroleum equipment and coal mining machinery. Pullman-Peabody, which supplies material-handling and food service equipment, had launched a $31-a-share tender offer for Joy on Dec. 2, and later proposed to sweeten the bid to $34 a share. The investor group was formed by Adler & Shaykin, a New York investment firm that specializes in leveraged buyouts.