UPDATE 1-Miner Inmet to make all-cash offer for Petaquilla

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PHILADELPHIA, July 6 (Reuters) - Inmet Mining Corp said on Sunday it would make an all-cash offer to acquire Petaquilla Copper Ltd (PTC.TO: Quote, Profile, Research, Stock Buzz), its partner in the Petaquilla copper project in Panama, for $2 per share.

The offer represents a 108-percent premium to the closing price of the Petaquilla Copper common shares as of July 4, the last trading day immediately prior to announcement, Inmet said.

The offer is subject to certain conditions, including receipt of regulatory clearances, the absence of any material adverse change in Petaquilla Copper and acceptance of the offer by Petaquilla Copper shareholders 50.1 percent or more of the the company's common stock on a fully-diluted basis, Inmet said.

Inmet said it entered into an agreement with certain institutional shareholders owning 15.1 million shares of Petaquilla Copper, or 9.38 percent of the company, which have agreed to tender their holdings under the offer.

Inmet and Petaquilla Copper are partners in a $3.5 billion copper deposit project in Panama. In May, Petaquilla Copper said Inmet would takeover management of the project to bring it to production as planned by 2013.

Petaquilla Copper owns 52 percent of the project and Inmet owns 48 percent. Teck Cominco (TCKb.TO: Quote, Profile, Research, Stock Buzz) has the option to take half of Petaquilla Copper's share by agreeing to fund about half of the mine's development.

Petaquilla Copper said in April that copper and zinc company Teck had not met conditions necessary to exercise that option. (Reporting by Jessica Hall; editing by Clarence Fernandez) (For more M&A news and our DealZone blog, go to here)