8-K 1 a2120789z8-k.htm 8-K
QuickLinks -- Click here to rapidly navigate through this document

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): October 22, 2003

AFFILIATED MANAGERS GROUP, INC.
(Exact name of Registrant as specified in charter)

Delaware
(State or other jurisdiction
of incorporation)		   0001-13459
(Commission
file number)		   043218510
(IRS employer
identification no.)


600 Hale Street, Prides Crossing, MA 01965
(Address of principal executive offices) (Zip code)

(617) 747-3300
(Registrant's telephone number, including area code)


Item 7. Exhibits.

        Exhibit 99.1 Registrant's Press Release dated October 22, 2003.


Item 12. Results of Operations and Financial Condition.

        The following information is being furnished under Item 12 of Form 8-K. On October 22, 2003, Registrant issued a press release setting forth its financial and operating results for the most recently completed quarter. A copy of this press release is attached hereto as Exhibit 99.1 and hereby incorporated by reference herein.

        The information in this Current Report on Form 8-K and the Exhibit attached hereto shall not be deemed "filed" for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the "Exchange Act") or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act, regardless of any general incorporation language in such filing.


SIGNATURES

        Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

  AFFILIATED MANAGERS GROUP, INC.

Date: October 22, 2003
/s/  DARRELL W. CRATE      
DARRELL W. CRATE
 Executive Vice President, Chief Financial Officer and Treasurer
(and also as Principal Financial and Accounting Officer)


QuickLinks

SIGNATURES