May 8, 2006

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

                            SCHEDULE 14A INFORMATION
                                 (Rule 14a-101)

                  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
[ ]     Definitive Additional Materials
[X]     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______________________________________________________________

















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The following  communication  is being  distributed  to all KeySpan  Corporation
("KeySpan") and National Grid employees  through internal email systems and will
be posted on the KeySpan/National Grid websites:

Integration update                  National Grid             KeySpan


Volume I Issue V                                              May 2006

                     Off and Running - National Grid-KeySpan
                    Integration Team Holds Successful Kickoff

On April 25-26,  the National  Grid-KeySpan  integration team met in Brooklyn to
launch the  integration  effort,  kicking off the process  that will combine the
companies,  with the goal of creating the premier  energy company in the nation.
During a strategy and planning session at KeySpan's headquarters, the team began
to frame the  integration  process and build a foundation for the strong working
relationships  that will ensure our success.  National Grid USA's  President and
CEO Mike Jesanis and KeySpan  Chairman  and CEO Bob Catell both  stressed to the
team just how critical the integration  planning is and talked of the tremendous
opportunity to grow the combined business in the U.S., while continuing to serve
our customers safely, reliably, efficiently and responsibly.

Time Line

Although the regulatory  approvals may take longer, the integration team has set
an ambitious  schedule to be ready for "Day 1" by December  31, 2006.  The first
tasks the team is charged with are to establish  their  sub-teams,  develop team
work  plans of what must be ready - and what  would be good to have  ready - for
implementation on Day 1, and to identify potential  challenges and opportunities
for a successful  integration.  The analysis and comparison of the "as is" state
for both  companies is expected to be completed by the end of July.  Then begins
the identification of the recommended  approach,  synergy  opportunities and the
design of the new combined  organization,  which are to be completed by October,
with  implementation   planning  taking  place  from  November  to  December  to
facilitate a Day 1 kickoff at the beginning of 2007.

The Integration Team will meet weekly,  alternating  between major National Grid
and KeySpan  locations.  This meeting  schedule was adopted  expressly to enable
employees  of both  companies  to see  the  integration  team  leads  and  their
sub-teams  in action at various  company  locations  as they move  through  this
process.  As all  employees  possess  unique  knowledge  about their  respective
functions  and  work  areas,  assistance  from  many  will  be  invaluable  to a
successful  integration.  The  Integration  Team  thanks you in advance for your
support.



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Future Updates

We will continue to keep you informed of the team's progress through Integration
Update, the integration intranet sites and face-to-face  communications.  If you
have questions at any time,  please feel free to contact your team leads (listed
in the first Integration Update); use the Integration Hotlines at 1-800-523-1044
(National     Grid)     or     1-888-698-4397      (KeySpan);      or     e-mail
IntegrationQuestions@us.ngrid.com or IntegrationQuestions@keyspanenergy.com.

NOTE:  Please  print and  distribute  to  employees in your area who do not have
computer access.














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

KeySpan intends to file with the Securities and Exchange  Commission (the "SEC")
a definitive proxy statement and other relevant documents in connection with the
proposed  acquisition of KeySpan by National Grid. We filed a preliminary  proxy
statement  with the SEC on April 28, 2006.  Investors  and  security  holders of
KeySpan are advised to read the proxy  statementd and other  relevant  documents
when they become available, as they will contain important information about the
transaction.  Investors and security holders may obtain a free copy of the proxy
statement  and other  documents  filed by KeySpan with the SEC, when they become
available, at the SEC's web site at http:/www.sec.gov.

KeySpan  and  its  directors,  executive  officers  and  other  members  of  its
management and employees may be deemed to be participants in the solicitation of
proxies from its security  holders in connection with the proposed  acquisition.
Information   concerning  the  interests  of  KeySpan's   participants   in  the
solicitation  is set forth in KeySpan's  Annual  Report on Form 10-K (filed with
the SEC on  February  28,  2006),  Quarterly  Report on Form 10-Q for the period
ended March 31, 2006, KeySpan's  preliminary proxy statement (filed with the SEC
on April  28,  2006)  and will be set forth in the  definitive  proxy  statement
relating to the acquisition when it becomes available.










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