EarthLink (ELNK) 10-Q 2003 Q1 Quarterly report

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Exhibit 99.1

CERTIFICATION PURSUANT TO
18 U.S.C. SECTION 1350,
AS ADOPTED PURSUANT TO
SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

        In connection with the Quarterly Report on Form 10-Q of EarthLink, Inc. (the "Company") for the period ending March 31, 2003 as filed with the Securities and Exchange Commission on the date hereof (the "Report"), I, Charles G. Betty, Chief Executive Officer of the Company, certify, pursuant to 18 U.S.C. § 1350, as adopted pursuant to § 906 of the Sarbanes-Oxley Act of 2002, to my knowledge that:

(1)

the Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and



(2)

the information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

/s/  CHARLES G. BETTY      

Charles G. Betty
Chief Executive Officer
May 15, 2003

A signed original of this written statement required by Section 906 has been provided to EarthLink, Inc. and will be retained by EarthLink, Inc. and furnished to the Securities and Exchange Commission or its staff upon request.

This certificate is being submitted in accordance with the procedure provided in Section III of SEC Release No. 33-8212, 34-47551, IC-25967 (March 21, 2003) for treatment as a document "accompanying" the Quarterly Report on Form 10-Q to which it is attached and not as a document "filed" as a part of such Quarterly Report. This certificate shall not be deemed incorporated by reference into any of EarthLink, Inc.'s Securities Act registration statements.

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CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350, AS ADOPTED PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002