Korea Zinc Co., which is fending off an unsolicited bid for control from a private equity firm, has roped in Bain Capital to buy back up to 18% outstanding shares of the Seoul-listed company.

Expert warns against winner's curse as stock price rises on counteroffer by Korea ZincBoth Korea Zinc and an alliance between private equity firm MBK Partners and Young Poong are making last-ditch efforts in their escalating battle to secure management rights over the world’s largest zinc smelter.

Korea Zinc Inc. said Wednesday it will buy back 2.66 trillion won (US$2 billion) worth of its own shares in a rare counteroffer to fend off a tender offer by private equity firm MBK Partners and Young Poong,

MBK Partners is open to considering a higher offer to take control of Korea Zinc Co. if rival suitors for the world’s biggest producer of refined zinc and lead emerge, a top executive of the private equity firm said.

MBK Partners sweetened its unsolicited bid for control of Korea Zinc Co. by about 14%, pushing the stock to a record and valuing the world’s biggest zinc smelter at 15.5 trillion won ($11.6 billion).Most Read from BloombergNJ Transit,

The vice chairman of Korea Zinc on Tuesday strongly condemned a takeover attempt by its major shareholder Young Poong, which teamed up with private equity firm MBK Partners for the bid, calling it a “predatory action” that would lead to the outflow of homegrown technology and put the country’s industrial competitiveness under threat.

Korea Zinc, the world’s largest zinc smelter, made a public tender offer Wednesday for an 18 percent stake of the company, countering Young Poong and MBK Partners’ offer for a controlling stake.

Korea Zinc Inc. said Wednesday it plans to make a counteroffer to buy back and cancel its own shares to fend off a tender offer by private equity firm MBK Partners and Young Poong, the biggest shareholder of the world's largest zinc smelter.