Update - Horse Hill, UK Weald Basin

Doriemus plc ("Doriemus" or "the Company") Update - Horse Hill, UK Weald Basin Doriemus plc (AIM: DOR) notes the comments in today's press in relation to theHorse Hill licences. The Company has been informed that the current twoexploration licences over the Horse Hill licence area and their expiry datesare as follows: the PEDL137 licence (within which the Horse Hill-1 well was drilled and whichwas the subject of the Company announcement of 9 April 2015) expires on 30September 2015; and PEDL246 licence expires on 30 June 2019. Doriemus has also been informed that the operator of the two licences, HorseHill Developments Limited* ("HHDL"), has already applied to the Oil & GasAuthority ("OGA") (formerly the Department of Energy and Climate Change) for aone year extension of the exploration period of PEDL137. The Company will update the market on this licence extension in due course. Further, the Company has been informed by the PEDL137 operator, HHDL, that itintends to conduct a flow test on Horse Hill-1 later in 2015 and that it hasalready submitted the applications to the authorities for their consent.Planning approval for a flow test on Horse Hill-1 is already in place, as thiswas included in the original Surrey County Council planning approval. Subjectto the results of the flow test being successful, the operator would seek, inconjunction with the OGA and other regulators, to move the PEDL137 licence intothe Production Period, via submission of a Field Development Plan to OGA. Doriemus interest in Horse Hill: The Horse Hill-1 well is located within onshore exploration license PEDL 137,on the northern side of the Weald Basin near Gatwick Airport. Doriemus owns a10% direct interest in Horse Hill Developments Ltd ("HHDL"). HHDL is a specialpurpose company that owns a 65% participating interest and operatorship oflicence PEDL 137 and the adjacent licence PEDL 246 in the UK Weald Basin. Theparticipants in the Horse Hill-1 well are HHDL with a 65% working interest andMagellan Petroleum Corporation with a 35% interest. Note *: The PEDL137 and PEDL246 licenses are held 35% by Magellan PetroleumCorporation and 65% by Horse Hill Developments Limited. Enquiries: Doriemus plcDonald Strang/Hamish Harris +44 (0) 20 7440 0640 Cairn Financial Advisers LLP:James Caithie / Carolyn Sansom +44 (0) 20 7148 7900 Public Relations:Square 1 Consulting Ltd +44 (0) 20 7929 5599David Bick/Mark Longson