SOUTHERN GAS NETWORKS PLC (the "Issuer")

(LEGAL IDENTIFIER NUMBER: 549300SPX8573VZ2SK79)

Notification of Investigation under s.25 of the Competition Act 1998

The Issuer has received notification from Gas and Electricity Markets Authority, the governing body of the Office of Gas and Electricity Markets, that it has opened an investigation under s.25 of the Competition Act 1998 into the conduct of Scotia Gas Networks Limited ("SGN") and any companies that form or previously formed part of the same corporate group which focusses on SGN's connections business. The Issuer is a wholly owned subsidiary of SGN.

The Issuer and SGN are cooperating fully with the investigation.

This announcement contains Inside Information for the purposes of Article 7 of the Market Abuse Regulation (EU) 596/2014 as it forms part of UK Domestic Law by virtue of the European Union (Withdrawal) Act 2018, as amended (the "UK Market Abuse Regulation").

For further information, please contact:

Alexander Rutherford

Treasurer

+44 (0)1293 818 316

[email protected]

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