OZ Minerals has poured cold water on rumours that Glencore Xstrata is preparing a takeover bid, declaring it has received no contact from the Swiss giant.
London media speculated over the weekend that Glencore had built a "secret" 10 per cent stake in OZ - which mines for copper and gold in South Australia - and was preparing to launch a full takeover soon.
The speculation sparked strong interest in OZ shares, which rose 6.7 per cent in early trading on Monday, but eased after OZ distanced itself from Glencore.
"The company advises it has not received a substantial shareholder notice from Glencore nor has OZ Minerals been approached by Glencore in regard to any proposal," said OZ in a statement.
Under ASX rules, shareholders must file a "substantial shareholder" notice as soon as they own 5 per cent or more of a company.
Local pundits were sceptical about the likelihood of a takeover, with most suggesting such a move would be at odds with Glencore's recently stated business strategy.
Glencore has recently opted to leave most of its undeveloped assets as they are, and focus instead on developing existing operations and bolt-on acquisitions.
Much of OZ's value relates to the undeveloped Carrapateena deposit in South Australia, with its one operating mine - the nearby Prominent Hill - being closer to the end of its life than the start, and suffering from rising costs.
Wilson HTM analyst Cameron Judd said he did not expect Glencore to mount a full takeover for OZ. "Never say never, but I don't think it's likely," he said.
Mr Judd said the outlook for copper markets was generally strong and South Australia was a good place to mine, but buying OZ Minerals would be at odds with the cost reduction process, including the sale of copper assets, that Glencore has under way.
"Glencore, or another entity with balance sheet strength, is more likely to emerge as a potential joint-venture partner at Carrapateena, and that would be a scenario I think OZ Minerals would be happy with too."
Carrapateena is considered highly prospective, but development is several years and many millions of dollars away.
OZ shares closed just 2¢ higher at $4.43.
OZ has in recent years been seen as a likely acquirer of assets, given it has long boasted a cash pile of almost $1 billion. But that cash pile has gradually been eroded by the Carrapateena purchase and dividend payments, to the point where it stood at just $432.9 million in the August results.