July 24, 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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Check the appropriate box:
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        Rule 14a-6(e)(2))
[ ]     Definitive Proxy Statement
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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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(1)  Title of each class of securities to which transaction applies:
     N/A______________________________________________________________
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     N/A______________________________________________________________

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     to Exchange  Act Rule 0-11 (set forth the amount on which the filing fee is
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The following  communication is being distributed to all KeySpan Corporation and
National Grid employees:

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

Volume 1 Issue XII                                                    July 2006
- --------------------------------------------------------------------------------

July 24, 2006

  National Grid and KeySpan File with New York State Public Service Commission

In a joint filing with the New York State Public  Service  Commission,  National
Grid and KeySpan  proposed a plan under which the merged  company  will  provide
customer  savings and will be better  positioned to serve customers by operating
efficiently,  managing energy supply costs and expanding programs to help reduce
energy use. The filing  highlights  customer  benefits  achieved because of what
National Grid and KeySpan can offer jointly, versus what either company could do
alone.

Permanent  savings of more than $500 million are  anticipated for New York State
customers during the10-year proposal,  possible only through the cost-reductions
generated from combining the companies.  Additional  benefits  coming to KeySpan
customers  include  low-income and supplier  choice  programs,  and  accelerated
infrastructure improvements.

The NYPSC  will be  reviewing  the  proposal  over an  approximately  nine month
period.  For more  details of the rate  filing,  employees  can access the press
release  on the  corporate  intranet  or  call  Media  Relations  for a copy  at
516-545-4547.


Additional Frequently Asked Questions

Has it been  determined  how many  jobs  will be lost as a result  of  combining
National Grid and KeySpan?

While we don't know where specific reductions may occur or which reductions will
come from current National Grid positions or KeySpan  positions,  to achieve the
estimated $200 million in synergy savings we expect a reduction of approximately
10 percent of the combined number of jobs between the two companies. These would
mainly be in support positions where duplication exists, rather than in field or
customer  service  positions.  Both National Grid and KeySpan have  historically
achieved merger reductions through attrition and voluntary programs, and plan to
continue this  practice.  The  Integration  Team will be developing the detailed
plans during the coming months and will communicate the information to employees
once it's determined.




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We're  always  told  how  customers  will  benefit  from the  mergers.  How will
employees benefit?

Employees  stand to  benefit  from  several  aspects of the  mergers,  including
opportunities to grow their careers as part of an international  and much larger
organization.  The addition of KeySpan and New England Gas to National Grid will
help the new  company  build  upon its gas and  electricity  industry  expertise
through  the  sharing  of best  practices.  As part of a  growing  international
company,  employees  will  also  have  the  opportunity  to  work  in  different
locations,  expand  their  knowledge  and  skills  of the  gas  and  electricity
business,  and interact with  employees from companies that may have a different
culture, which we can combine to make a more productive culture for one company.

Will pensions or benefits be affected?

Vested  pension  benefits  will not be affected.  Part of the joint  integration
process,  however,  does include a thorough review of National Grid, KeySpan and
New England Gas pay and benefit  programs.  Our goal is to provide  compensation
and benefit plans that are not only competitive,  but help us attract and retain
the talent we need to support our business growth. Employees will be informed of
any changes stemming from the review after decisions are made.

With  the two new  acquisitions,  what is the  total  number  of  customers  for
National Grid, both combined with the U.K. and the U.S. alone?

The company  will have 4.4 million  electric  customers  (including  1.1 million
electric customers KeySpan services for the Long Island Power Authority) and 3.4
million gas customers throughout New York,  Massachusetts,  Rhode Island and New
Hampshire.

Is there any future  probability of purchasing  either  National Fuel Gas or New
York State Electric and Gas (NYSEG)? What about the rumor that National Grid may
be acquired by the Spanish company Endesa?

We do not comment on rumors or speculation  about mergers and  acquisitions.  At
this time we are  concentrating  our efforts on ensuring a seamless  integration
with KeySpan and New England Gas.

Will people who hold  shares of KeySpan  stock be paid in cash or will they have
the option of receiving the same value in National Grid stock?

Once the merger occurs,  all outstanding  shares of KeySpan common stock will be
converted to the right to receive $42 per share in cash (the transaction price).
At that time, KeySpan shareholders will receive a cash payment,  which will have
tax  consequences.  KeySpan  common  stock  cannot be  exchanged  for  shares of
National Grid. The transaction only provides for a cash  consideration  for each
share.





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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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