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

                            SCHEDULE 14A INFORMATION
                                 (Rule 14a-101)

                  Proxy Statement Pursuant to Section 14(a) of
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                              KeySpan Corporation
                              -------------------
                (Name of Registrant as Specified in Its Charter)

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                                     -----
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The following  communications  were  distributed  to all  employees  through our
internal email system and will be posted on our internal KeySpan  website.  They
will also be printed and posted in common  areas of  KeySpan's  facilities  (i.e
elevator banks, employee lounges, areas where publications are generally located
and available for employees to pick up and read, etc.) for employees to read.


Communication #1:
- -----------------

First Two Issues of: National Grid/KeySpan Integration Update

As we move  forward with the National  Grid/KeySpan  integration,  communication
will  play a  critical  role.With  that in mind,  we've  attached  the first two
installments of what will become a series of National  Grid/KeySpan  Integration
Update communications.

The first two issues of this  publication  address  frequently  asked  questions
submitted by employees to the Merger Hotline,  including questions regarding the
effect of the transaction on their KeySpan Common Stock holdings in the Employee
Discount Stock Purchase Plan and the KeySpan 401(k) Plan.




                                       3



Communication #2.
- --------------------------------------------------------------------------------
nationalgrid                    KEYSPAN                  Integration Update
- --------------------------------------------------------------------------------
Volume I Issue I                                               March 2006
- --------------------------------------------------------------------------------

                      Your Top 10 Qs (and As) on the Merger

As we move forward with the National  Grid/KeySpan  integration,  it will become
easier to answer more of your questions about the merger. In the meantime, we've
put  together  the  first  in  what  will  be a  series  of  Integration  Update
communications  with  information  as complete as possible in these  preliminary
stages of the transaction.

Also,  managers and  officers  throughout  the Company  will address  issues and
concerns  specific to their areas as we move  through this  integration  process
together.

1. Why did KeySpan decide to sell?

The timing is favorable from both regulatory and economic  vantage  points.  New
federal  regulations  on  interstate  ownership of utilities  make it easier for
companies to buy and sell assets.  This has  resulted in  consolidations  in our
industry  as  companies  seek to  drive  increased  shareholder  value.  Utility
valuations  are also  relatively  high,  so selling now  provides an  attractive
opportunity to deliver significant value to our shareholders.

2. Why did we accept National Grid's offer?

National  Grid's  all-cash offer for KeySpan will provide our  shareholders  the
best return on their  investment,  with an immediate  premium to the  unaffected
closing  stock  price.  And from a customer  perspective,  National  Grid has an
impressive  track  record in  delivering  safe,  reliable,  efficient,  low-cost
service.  Finally, National Grid intends to leverage its technology expertise to
introduce  efficiencies  and best  practices that will improve  performance  and
benefit customers over the long term.

3. What attracted National Grid to KeySpan?

The KeySpan  acquisition is a natural  extension of National  Grid's U.S. growth
strategy.  KeySpan  is a leading  gas and  electric  delivery  company.  It's an
excellent  geographic,  operational  and  strategic  fit.  We also have a strong
operational  track  record  and  good  growth  prospects,  particularly  in  the
diversified,  strong and  growing  Long  Island and  metropolitan  areas,  which
provide an excellent foundation for continued economic growth.

The combined company, which will be the third largest energy delivery company in
the U.S., will have greater resources available to enhance generation assets and
energy  delivery  infrastructure,  as well as enjoy  synergies that will benefit
customers.

4. How will the transaction  impact our electric business  operations - the LIPA
relationship and electric generation?

LIPA  continues to receive the highest  level of service and we are committed to
continue that. The relationship  with LIPA is very important to KeySpan,  and we
will continue to operate and provide  services to LIPA with  existing  personnel
under  the  KeySpan  name.  Continuing  efficiency/service  investments  for the
benefit of LIPA's one million customers remains a high priority.

One thing to keep in mind:  Although  LIPA  doesn't  have a say in the  approval
process of our deal with  National  Grid, a change of control does allow them to
consider the Management  Services  Agreement (MSA) contract in default.  As many
employees know, we just completed  negotiations on a very favorable new contract
for LIPA's  customers  that would last through  2013.  So in the coming  months,
we'll be  working  hard to  convey  the  positive  nature  of this  deal to LIPA
customers.  We'll be working with government on all levels to keep them informed
of the benefits to consumers and our employees.  We'll also be helping LIPA with
its analysis and taking our own very detailed look into  potential  benefits for
gas and electric customers.


                                       4




                      Your Top 10 Qs (and As) on the Merger

Continued from front


As far as electric generation goes, National Grid has no current plans to divest
KeySpan's generation  portfolio,  which is substantially  supported by long-term
contracts  with  LIPA and the  attractive  characteristics  of the New York City
capacity market.

5. Who will be responsible for integrating the two companies? How will decisions
be made?

An Integration  Team with members from both  organizations  will be appointed to
carefully,  thoroughly  and  thoughtfully  study  how we  will  consolidate  the
businesses.  John Caroselli,  KeySpan EVP and Chief Strategy  Officer,  has been
selected  to lead the  National  Grid-KeySpan  integration  effort  on behalf of
KeySpan.  John will work with Kwong Nuey, SVP and Chief Information Officer, who
will be the  integration  team lead for National Grid.  They will put together a
team of National Grid and KeySpan  delegates who will work over the next several
months to identify how the combined  companies will operate once the merger goes
forward.

6. How will this  acquisition  affect my  department or a major project that I'm
working on?

Honestly,  it's  too soon to tell.  But  things  will  become  clearer  once the
Integration  Team begins to look at how we can combine our companies'  expertise
and best  practices to create  greater  efficiencies  and one stronger  company.
Throughout this process,  it's really  important for employees to remain focused
on providing the best possible service to customers.

7. Will there be cuts in union or management positions?

National Grid will honor all labor  agreements  currently in effect with KeySpan
unions,  and all KeySpan  employees  will become  National Grid  employees  upon
completion  of the  acquisition.  The  Integration  Team will  study how best to
integrate  the  businesses,  including  looking  at where we may have  duplicate
functions. They will be guided by how best to deliver safe, reliable,  efficient
service  to  customers.  As in  past  mergers,  we  expect  to  achieve  any job
reductions through attrition and voluntary programs.

8. Will facilities be closed or departments moved to different facilities?

We expect to find that certain facilities can be combined. But it's too early to
discuss  specifically  what may happen.  The Integration Team will be looking at
this and we will communicate decisions as soon as possible after they're made.

9. How will my benefits be affected?

Will KeySpan employees be moved into the National Grid compensation and benefits
plans? Both companies offer comprehensive  benefits packages.  As a condition of
the merger,  National  Grid will provide  non-union  KeySpan  employees  with an
aggregate  benefits package equivalent to KeySpan's current benefits program for
two years after the merger closes.  During the integration process, the benefits
plans at both KeySpan and National Grid will be reviewed. One of the Integration
Team's  requirements is to develop  recommendations  for a benefits  program for
non-union  employees;  National  Grid will  continue  to  provide  the  benefits
packages negotiated for KeySpan's union employees.  Going forward,  the combined
company is committed to providing a competitive wage and benefits package to all
employees.

10. Where is National Grid stock traded, and will employees be able to purchase
it at a discount?

National  Grid  ordinary  shares  are  traded in the U.K.  on the  London  Stock
Exchange  under the  ticker  symbol  "NG." In the U.S.,  National  Grid stock is
traded on the New York Stock  Exchange  as an  American  Depositary  Share (ADS)
under the ticker symbol NGG; each ADS represents  five ordinary shares traded on
the London  Exchange.  Currently,  there is no discount  stock purchase plan for
employees.  National Grid shares are,  however,  offered as an investment option
under National Grid 401(k) plans.


                                       5


Communication #3
- --------------------------------------------------------------------------------
nationalgrid                    KEYSPAN                  Integration Update
- --------------------------------------------------------------------------------
Volume I Issue II                                                 March 2006
- --------------------------------------------------------------------------------
                         Important Information Regarding
                KeySpan Common Stock Through Your Employee Plans

Since the National Grid  transaction  was announced,  employees have raised many
questions  regarding the effect of the transaction on their KeySpan Common Stock
holdings in the Employee  Discount  Stock  Purchase Plan and the KeySpan  401(k)
Plan.  The  following  answers  respond  to  employees'  most  frequently  asked
questions:

Employee Discount Stock Purchase Plan (EDSPP)
- ---------------------------------------------
Q. What happens to my shares of KeySpan  Common  Stock in my EDSPP  account once
the acquisition occurs?
A: Once the  acquisition  occurs,  National Grid will  purchase all  outstanding
shares of KeySpan  Common Stock for $42 per share (the  transaction  price).  At
that time,  any shares that you have in your  account will be converted to cash.
You  will  receive  a  payment  for  the  cash  proceeds  which  will  have  tax
consequences in the year in which the acquisition occurs.

Q. Can I exchange my shares of KeySpan Common Stock for shares of National Grid?
A: No.  The  transaction  only  provides  for a cash  purchase  of each share of
KeySpan Common Stock at $42.

Q. What are the tax  consequences  with  respect to shares  purchased  under the
current plan?
A: After the  acquisition,  you will  receive a cash payout equal to the $42 per
share transaction price. There are different tax consequences depending upon how
long you've held the shares in the EDSPP.  We are still  checking  the impact of
various IRS  pronouncements  on the tax  consequences  of selling stock acquired
under this EDSPP (and its  predecessors)  as it existed  prior to May 2003.  The
following  is a summary  of the  potential  tax  impact  from the sale of shares
purchased within the current (post May 2003) EDSPP:

For gain on sales of shares acquired under the current EDSPP (post May 2003)
A: In general,  your overall  taxable gain resulting from the sale on your stock
in the EDSPP to National Grid will be equal to the  difference  between the sale
price ($42) and the discounted  price (purchase price less the 10% discount) you
paid for the stock.

Part of the gain is compensation  (ordinary)  income,  and part is capital gain.
Under the current EDSPP (post May 2003) the compensation  (ordinary) income part
is an amount equal to the discount granted at the time of purchase.  The balance
of the gain is capital gain.  If the stock was held for more than one year,  the
capital gain part will be long term capital gain. If the stock was held for less
than one year, the capital gain part will be a short term capital gain.

PLEASE NOTE: You will receive  additional  information in future  communications
regarding sales of shares acquired under the EDSPP and related tax implications.
You should consult your tax advisor for more information regarding the potential
tax impact on your tax return.

Q.  Will I be able to  continue  my  contributions  to the  EDSPP up  until  the
transaction is consummated?
A: Currently,  you may continue to make  contributions to the EDSPP and continue
to receive a 10% discount on the purchase of KeySpan  shares  through the EDSPP.
However, the provisions of the EDSPP are subject to review by KeySpan's Board of
Directors at any time.

Q. How can I change my payroll deductions or enroll in the EDSPP?
A: In order to change your  payroll  deductions  or enroll in the EDSPP you must
complete  an  "EDSPP  Form  for  Payroll  Deduction  Authorization,   Change  or
Cancellation" and forward it to the appropriate payroll department listed on the
form. To access this form go to the Intranet  Homepage and click on Need a Form?
under Quick Links.  Once you have  accessed the forms page the EDSPP form can be
found under the Stock Plans Area.


                                       6



KeySpan 401(k) Plan
- -------------------
Q. Will the KeySpan Common Stock Fund remain an investment option in the Plan?
A. Until the transaction is consummated,  KeySpan  anticipates  that the KeySpan
Common Stock Fund will remain an investment  option in the Plan.  Therefore,  no
action needs to be taken at this time if you'd like to continue to invest in the
KeySpan  Common Stock Fund.  Once the  transaction is  consummated,  the KeySpan
Common Stock Fund will be eliminated as an option in the Plan.

Q. What will happen to my investment  in the KeySpan  Common Stock Fund once the
merger transaction is consummated?
A. At the time of merger,  National Grid will purchase all outstanding shares of
KeySpan  Common Stock for $42 per share and any holdings you have in the KeySpan
Common Stock Fund will be converted to cash.  At that time,  you will be able to
allocate  the cash  proceeds  to  another  investment  option  within the Plan's
then-current fund lineup.

Q. Can I still allocate contributions to the KeySpan Common Stock Fund?
A. Yes.  We  anticipate  that until the  transaction  is  consummated,  you will
continue to be able to allocate all or a portion of your  Pre-Tax  Contributions
and/or your Employer  Matching  Contributions  to the KeySpan Common Stock Fund.
Please  note  that  continued  investment  in any fund  offered  under the Plan,
including  the KeySpan  Common Stock Fund,  is subject to the  discretion of the
KeySpan Investment Review Committee.

Q. Will I still  receive a discount on the  purchase of KeySpan  Common Stock in
the Plan?
A. Yes.  If you are  currently  eligible,  you will  continue  to  receive a 10%
discount on the  purchase of KeySpan  Common  Stock in the KeySpan  Common Stock
Fund.

Q. Will I still receive  dividends on KeySpan Common Stock in the KeySpan Common
Stock Fund?
A. Yes. As long as KeySpan's Board of Directors  continues to declare dividends,
you will continue to receive  dividends on any KeySpan Common Stock holdings you
have in the Plan until the transaction is consummated.

Q. Can I exchange  my  holdings  in the  KeySpan  Common  Stock Fund to purchase
shares of National Grid?
A. No. Currently National Grid shares are not an investment option in the Plan.

Please be assured that  KeySpan is  committed to keeping you informed  about any
changes  to the  EDSPP  and  the  KeySpan  401(k)  Plan  and  will  continue  to
communicate  with you as KeySpan and National Grid work toward the  consummation
of the transaction.

If you have questions about your EDSPP account,  please contact Computershare at
(800)  666-7401.  If you have questions about your KeySpan 401(k) account please
contact Vanguard at 1-800-523-1188 or visit vanguard online at www.vanguard.com.
Any other questions you may have regarding how the National Grid  acquisition of
KeySpan  will  affect  your  holdings  in your  employee  plans  please  contact
KeySpan's  Stock Plans Hotline at (718) 403-3131 or e-mail the Stock Plans Group
at financial@keyspanenergy.com.

Additional Information and Where to Find It
- -------------------------------------------
KeySpan  intends to file with the Securities and Exchange  Commission  ("SEC") a
proxy  statement and other  relevant  documents in connection  with the proposed
transaction  between KeySpan and National Grid Investors and security holders of
KeySpan are advised to read the proxy  statement  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  transaction.
Information   concerning  the  interests  of  KeySpan's   participants   in  the
solicitation  is set forth in KeySpan's  most recent proxy  statement and Annual
Report on Form 10-K filed (filed with the Securities and Exchange  Commission on
March 30,  2005 and March 2,  2006,  respectively)  and will be set forth in the
proxy statement relating to the merger when it becomes available.


                                       7



Additional Information and Where to Find It
- -------------------------------------------
KeySpan intends to file with the Securities and Exchange  Commission (the "SEC")
a proxy  statement and other relevant  documents in connection with the proposed
acquisition  of KeySpan by National  Grid.  Investors  and  security  holders of
KeySpan are advised to read the proxy  statement  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  most recent proxy  statement and Annual
Report on Form 10-K (filed with the SEC on March 30, 2005 and February 28, 2006,
respectively)  and will be set  forth in the  proxy  statement  relating  to the
acquisition when it becomes available.



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