Shareholders of KeySpan Corporation (KSE) voted on Thursday, August 17, 2006, and approved a proposed Merger between KSE and National Grid US8 Inc., a wholly owned subsidiary of National Grid plc (NGG). With the approval, KSE will be a wholly owned subsidiary of NGG. Pursuant to the terms of the merger, each share of KSE Common Stock outstanding immediately prior to the consummation of the Merger will be converted into the right to receive $42.00 cash, without interest, per KSE share. The Merger is expected to become effective on Monday, August 27, 2007. This corporate action will be coordinated with the Options Clearing Corporation.

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