AFFILIATED MANAGERS GROUP, INC. 10-Q

Item 5. Other Information The Company’s Board of Directors has amended and restated the Company’s By-laws, effective as of the date of this Quarterly Report on Form 10-Q, to address administrative matters relating to meetings of stockholders, including rules of conduct at meetings, presiding officer selection and proposal information requirements, as well as to the notice provisions for meetings of our board of directors, in Sections 2, 3, and 12 of Article I, and Sections 3 and 10 of Article II. The preceding summary is qualified in its entirety by the text of the amended and restated By-laws, which are attached as Exhibit 3.1 to this Quarterly Report on Form 10-Q. Item 6. Exhibits The exhibits are listed on the Exhibit Index and are included elsewhere in this Quarterly Report on Form 10-Q. 39 Table of Contents EXHIBIT INDEX Exhibit No. Description 3.1 Amended and Restated By-Laws* 4.1 Indenture for Junior Subordinated Notes between Affiliated Managers Group, Inc., as issuer, and U.S. Bank National Association, as trustee, dated as of March 27, 2019 (incorporated by reference to Exhibit 4.1 to Affiliated Managers Group, Inc.’s Form 8-K, dated March 27, 2019). 4.2 Third Supplemental Indenture, dated as of July 13, 2021, between Affiliated Managers Group, Inc., as issuer, and U.S. Bank National Association, as trustee, including the form of Global Note attached as Annex A thereto (incorporated by reference to Exhibit 4.2 to Affiliated Managers Group, Inc.’s Current Report on Form 8-K filed July 13, 2021). 10.1 Second Amendment to Third Amended and Restated Term Credit Agreement, dated as of June 10, 2021, among Affiliated Managers Group, Inc., as borrower, Bank of America, N.A., as administrative agent, and the lenders party thereto (incorporated by reference to Exhibit 10.1 to Affiliated Managers Group, Inc.’s Current Report on Form 8-K filed June 11, 2021). 31.1 Certification of Registrant’s Chief Executive Officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002* 31.2 Certification of Registrant’s Chief Financial Officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002* 32.1 Certification of Registrant’s Chief Executive Officer pursuant to Section 906 of the Sarbanes-Oxley Act of 2002** 32.2 Certification of Registrant’s Chief Financial Officer pursuant to Section 906 of the Sarbanes-Oxley Act of 2002** 101 The following financial statements from the Registrant’s Quarterly Report on Form 10-Q for the quarter ended June 30, 2021 are filed herewith, formatted in XBRL (Inline eXtensible Business Reporting Language): (i) the Consolidated Statements of Income for the three- and six-month periods ended June 30, 2021 and 2020, (ii) the Consolidated Statements of Comprehensive Income for the three- and six-month periods ended June 30, 2021 and 2020, (iii) the Consolidated Balance Sheets at June 30, 2021 and December 31, 2020, (iv) the Consolidated Statements of Changes in Equity for the three- and six-month periods ended June 30, 2021 and 2020, (v) the Consolidated Statements of Cash Flows for the six-month periods ended June 30, 2021 and 2020, and (vi) the Notes to the Consolidated Financial Statements 104 The cover page from the Registrant’s Quarterly Report on Form 10-Q for the quarter ended June 30, 2021, formatted in XBRL (Inline eXtensible Business Reporting Language) and contained in Exhibit 101 † Indicates a management contract or compensatory plan * Filed herewith ** Furnished herewith 40 Table of Contents 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, thereunto duly authorized. AFFILIATED MANAGERS GROUP, INC. (Registrant) August 5, 2021 /s/ THOMAS M. WOJCIK Thomas M. Wojcik on behalf of the Registrant as Chief Financial Officer (and also as Principal Financial and Principal Accounting Officer) 41 Table of Contents QuickLinks PART I—FINANCIAL INFORMATION Item 1. Financial Statements AFFILIATED MANAGERS GROUP, INC. CONSOLIDATED STATEMENTS OF INCOME (in millions, except per share data) (unaudited) AFFILIATED MANAGERS GROUP, INC. CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (in millions) (unaudited) AFFILIATED MANAGERS GROUP, INC. CONSOLIDATED CONDENSED BALANCE SHEETS (in millions) (unaudited) AFFILIATED MANAGERS GROUP, INC. CONSOLIDATED STATEMENT OF CHANGES IN EQUITY (in millions) (unaudited) AFFILIATED MANAGERS GROUP, INC. CONSOLIDATED STATEMENTS OF CASH FLOWS (in millions) (unaudited) AFFILIATED MANAGERS GROUP, INC. NOTES TO CONSOLIDATED FINANCIAL STATEMENTS Item 2. Management's Discussion and Analysis of Financial Condition and Results of Operations Item 3. Quantitative and Qualitative Disclosures About Market Risk Item 4. Controls and Procedures PART II—OTHER INFORMATION Item 2. Unregistered Sales of Equity Securities and Use of Proceeds Item 5 . Other Information Item 6. Exhibits EXHIBIT INDEX SIGNATURES