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, in light of the Board’s appointment of an independent Chairman of the Board and in connection with the Board of Directors’ regular review of the Company’s governance and organizational documents. The amendments to the Company’s By-laws provide that the Company need not have a Lead Director if the Chairman of the Board of Directors is an independent director (within the meaning of the New York Stock Exchange listing standards). The summary above 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 Senior Notes between Affiliated Managers Group, Inc., as issuer, and U.S. Bank National Association, as trustee, dated as of June 5, 2020 (incorporated by reference to the Company’s Current Report on Form 8-K (No. 001-13459), filed June 5, 2020) 4.2 First Supplemental Indenture, dated as of June 5, 2020, 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 the Company’s Current Report on Form 8-K (No. 001-13459), filed June 5, 2020) 10.1† Amendment No. 1 to Affiliated Managers Group, Inc. 2011 Stock Option and Incentive Plan* 10.2† Amendment No. 1 to Affiliated Managers Group, Inc. 2006 Stock Option and Incentive Plan* 10.3† Amendment No. 1 to Affiliated Managers Group, Inc. Amended and Restated 2002 Stock Option and Incentive Plan* 10.4† Amendment No. 1 to Affiliated Managers Group, Inc. Amended and Restated 1997 Stock Option and Incentive Plan* 10.5† Affiliated Managers Group, Inc. 2020 Equity Incentive Plan (incorporated by reference to the Company’s Registration Statement on Form S-8 (No. 333-240091), filed July 24, 2020) 10.6† Form of Restricted Stock Unit Award Agreement pursuant to Affiliated Managers Group, Inc. 2020 Equity Incentive Plan* 10.7† Form of Restricted Stock Unit Award Agreement for Directors pursuant to Affiliated Managers Group, Inc. 2020 Equity Incentive Plan* 10.8† Form of Stock Option Award Agreement pursuant to Affiliated Managers Group, Inc. 2020 Equity Incentive Plan* 10.9† Form of Stock Option Award Agreement for Directors pursuant to Affiliated Managers Group, Inc. 2020 Equity Incentive Plan* 10.10† Form of Restricted Stock Unit Award Agreement pursuant to Affiliated Managers Group, Inc. 2002 Stock Option Incentive Plan* 10.11† Form or Stock Option Award Agreement pursuant to Affiliated Managers Group, Inc. Stock Option and Incentive Plan* 10.12† Annual Director Compensation* 10.13† Agreement, dated as of May 15, 2020, by and between Affiliated Managers Group, Inc. and Hugh P. B. Cutler* 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, 2020 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, 2020 and 2019, (ii) the Consolidated Statements of Comprehensive Income for the three- and six-month periods ended June 30, 2020 and 2019, (iii) the Consolidated Balance Sheets at June 30, 2020 and December 31, 2019, (iv) the Consolidated Statements of Changes in Equity for the three- and six-month periods ended June 30, 2020 and 2019, (v) the Consolidated Statements of Cash Flows for the six-month periods ended June 30, 2020 and 2019, 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, 2020, formatted in XBRL (Inline eXtensible Business Reporting Language) and contained in Exhibit 101 * 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) July 31, 2020 /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 6. Exhibits EXHIBIT INDEX SIGNATURES