Page 1 of 13 Pages UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (AMENDMENT NO.6)* MERRILL LYNCH & CO INC ------------------------------------------------------ (NAME OF ISSUER) Common Stock ------------------------------------------------------ (TITLE OF CLASS OF SECURITIES) 590188108 ------------------------------------------------------ (CUSIP NUMBER) December 31, 1998 ------------------------------------------------------ (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which this Schedule is filed: X Rule 13d-1(b) - Rule 13d-1(c) - Rule 13d-1(d) - * The remainder of this cover page shall be filled out for a reporting person`s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page. The information required in the remainder of this cover page shall not be deemed to be 'filed' for the purpose of Section 18 of the Securities Exchange Act of 1934 ('Act') or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes). (CONTINUED ON FOLLOWING PAGE(S)) -------------------- -------------------- CUSIP NO. 590188108 13G Page 2 of 13 Pages -------------------- -------------------- -------------------------------------------------------------------- 1- NAME OF REPORTING PERSON AXA Assurances I.A.R.D. Mutuelle S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON ------------------------------------------------------------------- 2- CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP * (A) [ ] (B) [X] ------------------------------------------------------------------- 3- SEC USE ONLY ------------------------------------------------------------------- 4- CITIZENSHIP OR PLACE OF ORGANIZATION France ------------------------------------------------------------------- NUMBER OF SHARES BENEFICIALLY OWNED AS OF December 31, 1998 BY EACH REPORTING PERSON WITH ----------------------------------------------- 5- SOLE VOTING POWER 2,601,047 ----------------------------------------------- 6- SHARED VOTING POWER 1,188,500 ----------------------------------------------- 7- SOLE DISPOSITIVE POWER 4,370,088 ----------------------------------------------- 8- SHARED DISPOSITIVE POWER 56,727 -------------------------------------------------------------------- 9- AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 4,426,815 (Not to be construed as an admission of beneficial ownership) ------------------------------------------------------------------- 10- CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES * |------| |------| ------------------------------------------------------------------- 11- PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 1.2% ------------------------------------------------------------------- 12- TYPE OF REPORTING PERSON * IC -------------------------------------------------------------------- * SEE INSTRUCTIONS BEFORE FILLING OUT! -------------------- -------------------- CUSIP NO. 590188108 13G Page 3 of 13 Pages -------------------- -------------------- -------------------------------------------------------------------- 1- NAME OF REPORTING PERSON AXA Assurances Vie Mutuelle S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON ------------------------------------------------------------------- 2- CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP * (A) [ ] (B) [X] ------------------------------------------------------------------- 3- SEC USE ONLY ------------------------------------------------------------------- 4- CITIZENSHIP OR PLACE OF ORGANIZATION France -------------------------------------------------------------------- NUMBER OF SHARES BENEFICIALLY OWNED AS OF December 31, 1998 BY EACH REPORTING PERSON WITH ----------------------------------------------- 5- SOLE VOTING POWER 2,601,047 ----------------------------------------------- 6- SHARED VOTING POWER 1,188,500 ----------------------------------------------- 7- SOLE DISPOSITIVE POWER 4,370,088 ----------------------------------------------- 8- SHARED DISPOSITIVE POWER 56,727 -------------------------------------------------------------------- 9- AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 4,426,815 (Not to be construed as an admission of beneficial ownership) ------------------------------------------------------------------- 10- CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES * |------| |------| ------------------------------------------------------------------- 11- PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 1.2% ------------------------------------------------------------------- 12- TYPE OF REPORTING PERSON * IC -------------------------------------------------------------------- * SEE INSTRUCTIONS BEFORE FILLING OUT! -------------------- -------------------- CUSIP NO. 590188108 13G Page 4 of 13 Pages -------------------- -------------------- -------------------------------------------------------------------- 1- NAME OF REPORTING PERSON AXA Conseil Vie Assurance Mutuelle (formerly Alpha Assurances Vie Mutuelle) S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON ------------------------------------------------------------------- 2- CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP * (A) [ ] (B) [X] ------------------------------------------------------------------- 3- SEC USE ONLY ------------------------------------------------------------------- 4- CITIZENSHIP OR PLACE OF ORGANIZATION France -------------------------------------------------------------------- NUMBER OF SHARES BENEFICIALLY OWNED AS OF December 31, 1998 BY EACH REPORTING PERSON WITH ----------------------------------------------- 5- SOLE VOTING POWER 2,601,047 ----------------------------------------------- 6- SHARED VOTING POWER 1,188,500 ----------------------------------------------- 7- SOLE DISPOSITIVE POWER 4,370,088 ----------------------------------------------- 8- SHARED DISPOSITIVE POWER 56,727 -------------------------------------------------------------------- 9- AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 4,426,815 (Not to be construed as an admission of beneficial ownership) ------------------------------------------------------------------- 10- CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES * |------| |------| ------------------------------------------------------------------- 11- PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 1.2% ------------------------------------------------------------------- 12- TYPE OF REPORTING PERSON * IC -------------------------------------------------------------------- * SEE INSTRUCTIONS BEFORE FILLING OUT! -------------------- -------------------- CUSIP NO. 590188108 13G Page 5 of 13 Pages -------------------- -------------------- -------------------------------------------------------------------- 1- NAME OF REPORTING PERSON AXA Courtage Assurance Mutuelle S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON ------------------------------------------------------------------- 2- CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP * (A) [ ] (B) [X] ------------------------------------------------------------------- 3- SEC USE ONLY ------------------------------------------------------------------- 4- CITIZENSHIP OR PLACE OF ORGANIZATION France -------------------------------------------------------------------- NUMBER OF SHARES BENEFICIALLY OWNED AS OF December 31, 1998 BY EACH REPORTING PERSON WITH ----------------------------------------------- 5- SOLE VOTING POWER 2,601,047 ----------------------------------------------- 6- SHARED VOTING POWER 1,188,500 ----------------------------------------------- 7- SOLE DISPOSITIVE POWER 4,370,088 ----------------------------------------------- 8- SHARED DISPOSITIVE POWER 56,727 -------------------------------------------------------------------- 9- AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 4,426,815 (Not to be construed as an admission of beneficial ownership) ------------------------------------------------------------------- 10- CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES * |------| |------| ------------------------------------------------------------------- 11- PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 1.2% ------------------------------------------------------------------- 12- TYPE OF REPORTING PERSON * IC -------------------------------------------------------------------- * SEE INSTRUCTIONS BEFORE FILLING OUT! -------------------- -------------------- CUSIP NO. 590188108 13G Page 6 of 13 Pages -------------------- -------------------- -------------------------------------------------------------------- 1- NAME OF REPORTING PERSON AXA (formerly AXA-UAP) S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON ------------------------------------------------------------------- 2- CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP * (A) [ ] (B) [ ] ------------------------------------------------------------------- 3- SEC USE ONLY ------------------------------------------------------------------- 4- CITIZENSHIP OR PLACE OF ORGANIZATION France -------------------------------------------------------------------- NUMBER OF SHARES BENEFICIALLY OWNED AS OF December 31, 1998 BY EACH REPORTING PERSON WITH ----------------------------------------------- 5- SOLE VOTING POWER 2,601,047 ----------------------------------------------- 6- SHARED VOTING POWER 1,188,500 ----------------------------------------------- 7- SOLE DISPOSITIVE POWER 4,370,088 ----------------------------------------------- 8- SHARED DISPOSITIVE POWER 56,727 -------------------------------------------------------------------- 9- AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 4,426,815 (Not to be construed as an admission of beneficial ownership) ------------------------------------------------------------------- 10- CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES * |------| |------| ------------------------------------------------------------------- 11- PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 1.2% ------------------------------------------------------------------- 12- TYPE OF REPORTING PERSON * HC -------------------------------------------------------------------- * SEE INSTRUCTIONS BEFORE FILLING OUT! -------------------- -------------------- CUSIP NO. 590188108 13G Page 7 of 13 Pages -------------------- -------------------- -------------------------------------------------------------------- 1- NAME OF REPORTING PERSON THE EQUITABLE COMPANIES INCORPORATED S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON 13-3623351 ------------------------------------------------------------------- 2- CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP * (A) [ ] (B) [ ] ------------------------------------------------------------------- 3- SEC USE ONLY ------------------------------------------------------------------- 4- CITIZENSHIP OR PLACE OF ORGANIZATION State of Delaware -------------------------------------------------------------------- NUMBER OF SHARES BENEFICIALLY OWNED AS OF December 31, 1998 BY EACH REPORTING PERSON WITH ----------------------------------------------- 5- SOLE VOTING POWER 2,588,547 ----------------------------------------------- 6- SHARED VOTING POWER 1,188,500 ----------------------------------------------- 7- SOLE DISPOSITIVE POWER 4,357,588 ----------------------------------------------- 8- SHARED DISPOSITIVE POWER 56,727 -------------------------------------------------------------------- 9- AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 4,414,315 ------------------------------------------------------------------- 10- CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES * |------| |------| ------------------------------------------------------------------- 11- PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 1.2% ------------------------------------------------------------------- 12- TYPE OF REPORTING PERSON * HC -------------------------------------------------------------------- * SEE INSTRUCTIONS BEFORE FILLING OUT! Item 1(a) Name of Issuer: Page 8 of 13 Pages -------------- MERRILL LYNCH & CO INC Item 1(b) Address of Issuer's Principal Executive Offices: ----------------------------------------------- 250 Versey Street New York, NY 10281 Item 2(a) Name of Person Filing: --------------------- AXA Conseil Vie Assurance Mutuelle, (formerly Alpha Assurances Vie Mutuelle) AXA Assurances I.A.R.D Mutuelle, AXA Assurances Vie Mutuelle, and AXA Courtage Assurance Mutuelle, as a group (collectively, the 'Mutuelles AXA'). AXA (formerly AXA-UAP) The Equitable Companies Incorporated (the 'Equitable Companies') (Please contact Patrick Meehan at (212) 641-8234 with any questions.) Item 2(b) Address of Principal Business Office: ------------------------------------ AXA Conseil Vie Assurance Mutuelle 100-101 Terrasse Boieldieu 92042 Paris La Defense France AXA Assurances I.A.R.D Mutuelle and AXA Assurances Vie Mutuelle 21, rue de Chateaudun 75009 Paris France AXA Courtage Assurance Mutuelle 26, rue Louis le Grand 75002 Paris France AXA 9 Place Vendome 75001 Paris France The Equitable Companies Incorporated 1290 Avenue of the Americas New York, New York 10104 Page 9 of 13 Pages Item 2(c) Citizenship: ----------- Mutuelles AXA and AXA France Equitable Companies - Delaware Item 2(d) Title of Class of Securities: ---------------------------- Common Stock Item 2(e) CUSIP Number: ------------ 590188108 Item 3. Type of Reporting Person: ------------------------ Equitable Companies as a parent holding company, in accordance with 240.13d-1 (b)(ii)(G). The Mutuelles AXA, as a group, acting as a parent holding company. AXA as a parent holding company.