Announces Effect of Share Acquisition by Invecture Group on Shareholder Rights Plan

Toronto and Phoenix, AZ - December 12, 2008 - Frontera Copper Corporation (FCC:TSX, FCC.NT:TSX, FCC.NT.A:TSX) reports on the current status of Frontera's Shareholder Rights Plan (the "SRP"). On December 9, 2008, Invecture Group, S.A. de C.V. ("Invecture") announced that Invecture had acquired additional common shares of Frontera, bringing its aggregate holdings to 21.45% of the outstanding common shares of Frontera. As a consequence, Invecture became an "Acquiring Person" pursuant to Frontera's SRP. In the absence of a waiver of the application of the SRP, the Rights issued pursuant to the SRP would separate from the common shares and become exercisable at the close of business on December 23, 2008. If the Rights become exercisable, each Right (other than the Rights associated with the shares held by Invecture) would entitle the holder to purchase for Cdn$20 common shares of Frontera having an aggregate market price of Cdn$40.

Invecture has informally notified Frontera that it became an Acquiring Person by inadvertence, and that it intends to reduce its shareholdings to below 20%. Pursuant to the SRP, the Board of Directors may waive the application of the SRP in such circumstances, in which case the Rights would not separate or become exercisable as described above.

ABOUT FRONTERA COPPER CORPORATION

Frontera Copper is a Canadian mining, development and exploration company whose principal activity is the production of copper cathode from the Piedras Verdes run-of-mine heap-leach copper operation in Sonora, Mexico. Based on the January 1, 2008 ore reserves and the estimated recoverable copper contained on the leach pads at December 31, 2007, approximately 1 billion pounds of copper are projected to be produced over the remaining 17-year life of the operation.

For further information, please see Frontera Copper's website at www.fronteracopper.com or contact:

Rodney Prokop
Vice President, Investor Relations
(602) 424-5483
ir@fronteracopper.com

Alan Edwards
President and Chief Executive Officer
(602) 424-5488