July 20, 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. )

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[ ]     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)

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The following  communication  is being  distributed  to all KeySpan  Corporation
employees through internal email system.


To:      KeySpan Employees
From:    Mike Jesanis and Bob Catell
Re:      Culture Integration - Assessment Process
Date:    July 20, 2006

This communication will be the first of many that will discuss the importance of
creating a new culture as part of the  successful  integration  of National Grid
and KeySpan. As we move forward with our integration work, a critical element in
our success will be our ability to develop this unified  culture.  While we know
that there will be differences  between the entities (and even within them),  it
is essential that we merge not only our operations,  but also our organizational
values and norms of behavior.

In order for us to do that, we must be well  informed as to the current  culture
you work within and also your  thinking  about the  desired  culture for the new
enterprise.  We want to hear from  people  representing  all  groups  within our
organizations - both union and management.

To facilitate this effort, we are working with the HayGroup, a global management
consulting  firm, to assist in this culture  integration.  Hay has a tool called
"Culture-Sort"  that we will  be  asking  a broad  cross-section  of  people  to
complete as part of this process. The tool is on-line,  easy to use and actually
fun to complete. The tool asks you to take 56 dimensions of culture that Hay has
benchmarked as being important in successful cultures and place them on a normal
curve of importance in the current  culture  (either  National Grid or Keyspan).
The tool then asks you to do the same process again but, this time, to place the
attributes  on the  curve  based on the  ideal  new  culture - what you want the
integrated company to look like.

Please be assured  that all of this data is  completely  anonymous.  We will see
only aggregate reports, no individual information.  The data will be analyzed by
Hay to determine the key areas of culture that are similar and where differences
exist. Focus groups will also be held. At that point, Hay will present the model
of the desired  culture for final  discussion and approval.  We will then lead a
series of meetings  within the company to develop  specific areas and approaches
to  mange  the  change,  such  as  large  group  meetings,  alignment  sessions,
communications, etc.

In order to complete  the  Culture-Sort,  many of you will be receiving an email
directly  from Hay  with  log-in  information.  If you  have  any  questions  or
concerns,  please contact Ruth Bramson at  508-389-3400  or Elaine  Weinstein at
718-403-2349 at KeySpan.

We appreciate your involvement in this important process.  We know that managing
change is always stressful. However, working together, we can create a positive,
effective work environment for our new organization.


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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.














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