Prospectus Supplement Filing Under
Dated: August 12, 1999 Rules 424(b)(3) and 424(c)
To Prospectus dated May 27, 1998 Registration File No. 333-53657
KEYSPAN CORPORATION
INVESTOR PROGRAM
Effective May 20, 1999, MarketSpan Corporation changed its corporate name
to KeySpan Corporation, and is currently doing business as KeySpan Energy. As of
such date, the MarketSpan Corporation Investor Program is now the "KeySpan
Corporation Investor Program."
In terms of the Prospectus, dated May 27, 1998, relating to the Investor
Program:
- References to MarketSpan Corporation are changed to read KeySpan
Corporation.
- References to the "Company" should be read to mean KeySpan Corporation
rather than MarketSpan Corporation.
Any questions regarding the KeySpan Corporation Investor Program should be
directed to a KeySpan representative at 718-403-3196.
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This Prospectus Supplement should be affixed to your copy of the
prospectus dated May 27, 1998.
