Air Products and Chemicals said on Wednesday it filed proxy materials to elect three nominees to the board of Airgas as it bids to take control of Airgas.

The filing comes after Air Products said in May it would push the board slate, which includes John Clancey, chairman emeritus of shipping company Maersk; Robert Lumpkins, board chairman of fertilizer producer Mosaic; and Ted Miller, former chief executive officer of wireless communication provider Crown Castle International Corp.

Air Products went hostile in February in its bid for rival Airgas, the largest U.S. distributor of industrial gases and related equipment, offering $60 per share in cash or roughly $5.1 billion.

In a statement in response to preliminary proxy materials filed by Air Products, Airgas said its board continues to recommend stockholders reject the Air Products offer.