Rockhopper Regulatory News (RKH)

Embargoed: 0700hrs 9 January 2012

Rockhopper Exploration plc

("Rockhopper" or the "Company")

End of Drilling Campaign

Rockhopper Exploration plc (AIM: RKH), the North Falkland Basin oil and gas exploration company, announces that the Ocean Guardian drilling unit has been towed successfully from the 14/15-4 well location and is now off hire to Rockhopper.

14/15-4 was the final well in Rockhopper's first North Falkland Basin drilling campaign, which has lasted from 16 April 2010 to 8 January 2012.

The Company estimates that it will have over USD $100 million of cash resources available once all charges for completing the drilling campaign have been accounted for.

Sam Moody, Chief Executive, commented,

"This marks the end of what has been a highly successful and safe drilling campaign. We have operated ten wells, conducted two Drill Stem Tests, two short offset sidetracks and collected in excess of 450m of core with the Ocean Guardian on hire to us for a total of 397 days. I would like to thank the entire Rockhopper team and our contractors for their efforts which have resulted in seven successful wells of our ten drilled, with three oil discoveries, three gas discoveries, multiple successful Sea Lion appraisal wells and a successful appraisal well on Casper."

Enquiries:

Rockhopper Exploration plc

Sam Moody - Chief Executive

Tel. +44 (0)20 7920 2340 (via M: Communications)

M: Communications

Patrick d'Ancona or Ben Simons

Tel. +44 (0)20 7920 2347

Canaccord Genuity Limited

Charles Berkeley / Henry Fitzgerald-O'Connor

Tel. +44 (0) 20 7050 6500

Notes to Editors

Rockhopper was established in February 2004 with a strategy to invest in and carry out an offshore oil exploration programme to the north of the Falkland Islands. The Company floated on AIM in August 2005 and holds a 100 per cent. interest in four offshore production licences: PL023, PL024, PL032 and PL033 which cover approximately 3,800 sq. km. Rockhopper also farmed in (7.5% working interest) to licences PL003 and PL004, which are operated by Desire Petroleum. In addition to the original farm-in, and in consideration for drilling one well on the north-western acreage of licence PL004, known as Area 1, which contains the extension to the Sea Lion field as well as the Beverley, Casper and Casper South features, Rockhopper farmed-in with operatorship and an aggregate 60% interest in Area 1.

An extensive work programme has been carried out over a number of years on the licences operated by Rockhopper. This has included 2D and 3D Seismic and Controlled Source Electromagnetic Mapping (CSEM). In February 2010, the Ocean Guardian drilling rig arrived in Falkland waters to carry out a multi-well drilling campaign. Rockhopper drilled an exploration well on its Sea Lion prospect during April and May 2010, the result of which was the first oil discovery and Contingent Oil Resource in the North Falkland Basin. The Sea Lion

discovery was successfully tested during September 2010 and June 2011 and was the first oil to flow to surface in Falkland Islands waters. Rockhopper's drilling campaign lasted from 16 April 2010 to 8 January 2012 and resulted in seven successful wells of the ten drilled, with three oil discoveries, three gas discoveries, multiple successful Sea Lion appraisal wells and a successful appraisal well on Casper.

Rockhopper contracted seismic vessels MV Polarcus Asima and Nadia to carry out a 3D seismic survey over areas of licences PL024, PL032 and PL033 which were not previously defined by 3D, as well as adjacent areas. Data over the southern portion of licences PL032 and PL033 has been fast track processed and an initial interpretation has now been completed. The balance of the newly acquired 3D seismic data is still being processed and the Company expects it will be available for interpretation during January 2012.

Rockhopper Exploration plc www.rockhopperexploration.co.uk