August 1, 2006

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                            SCHEDULE 14A INFORMATION

                  Proxy Statement Pursuant to Section 14(a) of
            the Securities and Exchange Act of 1934 (Amendment No. )

Filed by the Registrant  [X]
Filed by a Party other than the Registrant  [ ]

Check the appropriate box:
[ ]     Preliminary Proxy Statement
[ ]     Confidential, For Use of the Commission Only (as permitted by
        Rule 14a-6(e)(2))
[ ]     Definitive Proxy Statement
[X]     Definitive Additional Materials
[ ]     Soliciting Material Pursuant to Section 240.14a-12

                              KeySpan Corporation
                              -------------------
                (Name of Registrant as Specified in Its Charter)

                                     (N/A)
                                     -----
    (Name of Person(s) Filing Proxy Statement, if Other Than the Registrant)

Payment of Filing Fee (Check the appropriate box):
[X]     No fee required.
[ ]     Fee computed on table below per Exchange Act Rules 14a-6(i)(1) and 0-11.

(1)  Title of each class of securities to which transaction applies:
     N/A______________________________________________________________
(2)  Aggregate number of securities to which transaction applies:
     N/A______________________________________________________________
(3)  Per unit price or other underlying value of transaction  computed  pursuant
     to Exchange  Act Rule 0-11 (set forth the amount on which the filing fee is
     calculated and state how it was determined):
     N/A______________________________________________________________
(4)  Proposed maximum aggregate value of transaction:
     N/A______________________________________________________________
(5)  Total fee paid:
     N/A______________________________________________________________






[  ] Fee paid previously with preliminary materials.

[  ] Check box if any part of the fee is offset as provided by Exchange Act Rule
     0-11(a)(2)  and identify the filing for which the  offsetting  fee was paid
     previously.  Identify the previous filing registration statement number, or
     the Form or Schedule and date of its filing.

(1)  Amount Previously Paid:
     N/A______________________________________________________________
(2)  Form, Schedule or Registration Statement No.:
     N/A______________________________________________________________
(3)  Filing Party:
     N/A______________________________________________________________
(4)  Date Filed:
    N/A______________________________________________________________












The following  communication is being distributed to all KeySpan Corporation and
National Grid employees:

Integration Update                 National Grid                        KeySpan
- --------------------------------------------------------------------------------

Volume 1 Issue XIII                                                 August 2006
- --------------------------------------------------------------------------------

August 1, 2006

             National Grid Shareholders Approve KeySpan Acquisition

National Grid shareholders yesterday  overwhelmingly approved the acquisition of
KeySpan  Corporation  during  the  company's  Extraordinary  General  Meeting in
London.  This  approval  is  another  step  in the  process  of  completing  the
transaction.

On July 21,  National Grid and KeySpan filed for approval of the merger with the
New York State Public  Service  Commission,  and in May the companies  filed for
approval from the U.S.  Federal Energy  Regulatory  Commission.  The transaction
gained clearance on its filings in compliance with federal antitrust and foreign
investment  requirements  in  July.  A  filing  with  the New  Hampshire  Public
Utilities Commission is expected shortly.


Additional Information and Where to Find It
- -------------------------------------------

In connection with the proposed merger, the Company has filed a definitive proxy
statement with the Securities and Exchange Commission.  BEFORE MAKING ANY VOTING
OR  INVESTMENT  DECISION,  THE  COMPANY  STOCKHOLDERS  ARE  URGED  TO  READ  THE
DEFINITIVE PROXY STATEMENT BECAUSE IT CONTAINS  IMPORTANT  INFORMATION ABOUT THE
PROPOSED MERGER. The definitive proxy statement is also available free of charge
at  the  Securities  and  Exchange   Commission's  website,   www.sec.gov,   and
stockholders  of the  Company are also able to obtain  additional  copies of the
definitive proxy statement free of charge by directing their requests to KeySpan
Corporation One MetroTech Center, Brooklyn, New York 1120-3850.

The  Company  and its  directors  and  executive  officers  may be  deemed to be
participants in the  solicitation of proxies from its stockholders in connection
with the proposed merger.  Information concerning the interests of the Company's
participants in the  solicitation is set forth in the Company's proxy statements
and Annual  Reports  on Form 10-K,  previously  filed  with the  Securities  and
Exchange  Commission,  and in the  definitive  proxy  statement  relating to the
merger.