Lodge with the Stock Exchange (which may publicise) and with the Panel. A copy must also be sent to the company the voting securities of which (or the rights over the voting securities of which) are acquired.

Date of disclosure 22 OCTOBER 2009

DISCLOSURE UNDER RULE 6 OF THE IRISH TAKEOVER PANEL
ACT, 1997, SUBSTANTIAL ACQUISITION RULES, 2007 ("SARs")

Date of Acquisition: 21 OCTOBER 2009

Acquisition in
ISLAND OIL & GAS PLC (name of company)

(1) Class of voting securities (e.g. ordinary shares)	Number of voting securities/rights over voting securities acquired	If rights over voting securities acquired, as opposed to the securities themselves specify nature of rights
ORDINARY SHARES OF €0.01 EACH	NIL securities 15,250,000 rights	IRREVOCABLE COMMITMENTS
(2) Resultant total holding of voting securities (and % of total voting securities in issue)	Resultant total holding of rights over voting securities (and % of total voting securities in issue)	Total percentage
21,000 (0.02%)	40,250,000 (29.61%)	40,271,000 (29.63%)
(3) Party making disclosure SAN LEON ENERGY PLC
(4)(a) Name of person acquiring securities or rights over securities SAN LEON ENERGY PLC and, if different, beneficial owner ................................................................................................
(b) Names of any other persons acting in concert (see SAR 3) PURSUANT TO RULE 3.3(b)(ii)(1) OF PART A OF THE TAKEOVER RULES THERE IS A PRESUMPTION THAT EACH DIRECTOR OF SAN LEON ENERGY PLC IS ACTING IN CONCERT WITH SAN LEON ENERGY PLC. PHILIP THOMPSON, A DIRECTOR OF SAN LEON ENERGY PLC, HOLDS 21,000 ORDINARY SHARES IN ISLAND OIL & GAS PLC

Signed, for and on behalf of the party named in (3) above .Oisin Fanning

(Also print name of signatory) OISIN FANNING

Telephone and extension number + 353 (0) 1291 6292

Note 1. Under SAR 3, the holdings of and acquisitions by persons acting in concert must be aggregated and treated as a holding of or acquisition by one person. SAR 8(b) requires persons who must aggregate holdings to disclose certain disposals.

Note 2. "Stock Exchange": see definition in Rule 2.1(a) of Part A of the Takeover Rules.

For details of the SARs disclosure requirements, see Rules 4, 6 and 8(b) of the SARs. If in doubt, consult the Panel.

This information is provided by RNS
The company news service from the London Stock Exchange

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Disclosure Form SAR 6