X0202 SCHEDULE 13D/A 0000947871-26-000007 0000915191 XXXXXXXX LIVE 1 Class A Common Stock ("Class A Shares") 05/13/2026 false 0001336917 904311107 Under Armour, Inc.

101 PERFORMANCE DRIVE BALTIMORE MD 21230

Sean J. Skiffington 647.280.5756 Allen Overy Shearman Sterling US LLP Commerce Court West, 199 Bay Street Toronto A6 M5L 1E8 Ryan E. Robski 416.302.1391 Allen Overy Shearman Sterling US LLP Commerce Court West, 199 Bay Street Toronto A6 M5L 1E8 0000938869 N V. PREM WATSA b OO N Z4 0.00 45300872.00 0.00 45300872.00 45300872.00 N 24.0 IN Y THE SECOND 810 HOLDCO LTD. b OO N Z4 0.00 45300872.00 0.00 45300872.00 45300872.00 N 24.0 CO Y THE SECOND 1109 HOLDCO LTD. b OO N Z4 0.00 45300872.00 0.00 45300872.00 45300872.00 N 24.0 CO 0001217251 N THE SIXTY TWO INVESTMENT COMPANY LIMITED b OO N A1 0.00 45300872.00 0.00 45300872.00 45300872.00 N 24.0 CO 0000915191 N FAIRFAX FINANCIAL HOLDINGS LIMITED b OO N Z4 0.00 45300872.00 0.00 45300872.00 45300872.00 N 24.0 CO 0001275984 N FFHL GROUP LTD. b OO N Z4 0.00 34077356.00 0.00 34077356.00 34077356.00 N 18.0 CO 0001450019 N FAIRFAX (BARBADOS) INTERNATIONAL CORP. b OO N C8 0.00 60950.00 0.00 60950.00 60950.00 N 0.0 CO Y WENTWORTH INSURANCE COMPANY LTD. b OO N C8 0.00 60950.00 0.00 60950.00 60950.00 N 0.0 CO 0001275996 N FAIRFAX (US) INC. b OO N DE 0.00 31098326.00 0.00 31098326.00 31098326.00 N 16.5 CO Y ODYSSEY GROUP HOLDINGS, INC. b OO N DE 0.00 11280564.00 0.00 11280564.00 11280564.00 N 6.0 CO 0001243947 N ODYSSEY REINSURANCE COMPANY b OO N CT 0.00 11280564.00 0.00 11280564.00 11280564.00 N 6.0 CO Y HUDSON INSURANCE COMPANY b OO N DE 0.00 265190.00 0.00 265190.00 265190.00 N 0.1 CO Y HUDSON EXCESS INSURANCE COMPANY b OO N DE 0.00 167670.00 0.00 167670.00 167670.00 N 0.1 CO 0000109261 N ZENITH NATIONAL INSURANCE CORP. b OO N DE 0.00 75440.00 0.00 75440.00 75440.00 N 0.0 CO 0001499301 N ZENITH INSURANCE COMPANY b OO N CA 0.00 75440.00 0.00 75440.00 75440.00 N 0.0 CO 0001168338 N CRUM & FORSTER HOLDINGS CORP. b OO N DE 0.00 19742322.00 0.00 19742322.00 19742322.00 N 10.5 CO 0000101618 N UNITED STATES FIRE INSURANCE COMPANY b OO N DE 0.00 19742322.00 0.00 19742322.00 19742322.00 N 10.5 CO 0001276001 N THE NORTH RIVER INSURANCE COMPANY b OO N NJ 0.00 4862016.00 0.00 4862016.00 4862016.00 N 2.6 CO Y FAIRFAX UK HOLDINGS LIMITED b OO N X0 0.00 2918080.00 0.00 2918080.00 2918080.00 N 1.5 CO Y BRIT GROUP HOLDINGS LIMITED b OO N X0 0.00 2918080.00 0.00 2918080.00 2918080.00 N 1.5 CO Y BRIT INSURANCE HOLDINGS LIMITED b OO N X0 0.00 2918080.00 0.00 2918080.00 2918080.00 N 1.5 CO Y BRIT REINSURANCE (BERMUDA) LIMITED b OO N D0 0.00 2918080.00 0.00 2918080.00 2918080.00 N 1.5 CO Y 1102952 B.C. UNLIMITED LIABILITY COMPANY b OO N A1 0.00 11223516.00 0.00 11223516.00 11223516.00 N 5.9 CO 0002060257 N ALLIED WORLD ASSURANCE COMPANY HOLDINGS, LTD b OO N D0 0.00 11223516.00 0.00 11223516.00 11223516.00 N 5.9 CO Y ALLIED WORLD ASSURANCE COMPANY HOLDINGS I, LTD b OO N D0 0.00 11223516.00 0.00 11223516.00 11223516.00 N 5.9 CO Y ALLIED WORLD ASSURANCE COMPANY, LTD b OO N D0 0.00 11223516.00 0.00 11223516.00 11223516.00 N 5.9 CO Y ALLIED WORLD ASSURANCE HOLDINGS (IRELAND) LTD b OO N D0 0.00 8408214.00 0.00 8408214.00 8408214.00 N 4.5 CO Y ALLIED WORLD ASSURANCE HOLDINGS (U.S.) INC. b OO N D0 0.00 8408214.00 0.00 8408214.00 8408214.00 N 4.5 CO Y ALLIED WORLD INSURANCE COMPANY b OO N NH 0.00 8408214.00 0.00 8408214.00 8408214.00 N 4.5 CO Y AW UNDERWRITERS INC. b OO N DE 0.00 624950.00 0.00 624950.00 624950.00 N 0.3 CO Y ALLIED WORLD SPECIALTY INSURANCE COMPANY b OO N DE 0.00 624950.00 0.00 624950.00 624950.00 N 0.3 CO Class A Common Stock ("Class A Shares") Under Armour, Inc. 101 PERFORMANCE DRIVE BALTIMORE MD 21230 Pursuant to Rule 13d-2 promulgated under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), this Amendment No. 1 to Schedule 13D (this "Amendment") amends the statement on Schedule 13D filed with the United States Securities and Exchange Commission (the "SEC") on January 1, 2026 (as amended and supplemented prior to the date hereof, the "Original Schedule 13D" and, as amended and supplemented by this Amendment, the "Schedule 13D") by Fairfax Financial Holdings Limited and certain of its affiliates relating to the class A common stock ("Shares"), of Under Armour, Inc. ("Under Armour"). The following amendments to Items 2, 5 and 7 of the Original Schedule 13D are hereby made: Item 2 of the Original Schedule 13D is hereby amended and restated in its entirety to read as follows: (i) V. PREM WATSA (ii) THE SECOND 810 HOLDCO LTD. (iii) THE SECOND 1109 HOLDCO LTD. (iv) THE SIXTY TWO INVESTMENT COMPANY LIMITED (v) FAIRFAX FINANCIAL HOLDINGS LIMITED (vi) FFHL GROUP LTD. (vii) FAIRFAX (BARBADOS) INTERNATIONAL CORP. (viii) WENTWORTH INSURANCE COMPANY LTD. (ix) FAIRFAX (US) INC. (x) ODYSSEY GROUP HOLDINGS, INC. (xi) ODYSSEY REINSURANCE COMPANY (xii) HUDSON INSURANCE COMPANY (xiii) HUDSON EXCESS INSURANCE COMPANY (xiv) ZENITH NATIONAL INSURANCE CORP. (xv) ZENITH INSURANCE COMPANY (xvi) CRUM & FORSTER HOLDINGS CORP. (xvii) UNITED STATES FIRE INSURANCE COMPANY (xviii) THE NORTH RIVER INSURANCE COMPANY (xix) FAIRFAX UK HOLDINGS LIMITED (xx) BRIT GROUP HOLDINGS LIMITED (xxi) BRIT INSURANCE HOLDINGS LIMITED (xxii) BRIT REINSURANCE (BERMUDA) LIMITED (xxiii) 1102952 B.C. UNLIMITED LIABILITY COMPANY (xxiv) ALLIED WORLD ASSURANCE COMPANY HOLDINGS, LTD (xxv) ALLIED WORLD ASSURANCE COMPANY HOLDINGS I, LTD (xxvi) ALLIED WORLD ASSURANCE COMPANY, LTD (xxvii) ALLIED WORLD ASSURANCE HOLDINGS (IRELAND) LTD (xxviii) ALLIED WORLD ASSURANCE HOLDINGS (U.S.) INC. (xxix) ALLIED WORLD INSURANCE COMPANY (xxx) AW UNDERWRITERS INC. (xxxi) ALLIED WORLD SPECIALTY INSURANCE COMPANY (i) 95 Wellington Street West, Suite 800, Toronto, Ontario, Canada M5J 2N7 (ii) 95 Wellington Street West, Suite 800, Toronto, Ontario, Canada M5J 2N7 (iii) 95 Wellington Street West, Suite 802, Toronto, Ontario, Canada M5J 2N7 (iv) 1600 Cathedral Place, 925 West Georgia St., Vancouver, British Columbia, Canada V6C 3L2 (v) 95 Wellington Street West, Suite 800, Toronto, Ontario, Canada M5J 2N7 (vi) 95 Wellington Street West, Suite 800, Toronto, Ontario, Canada M5J 2N7 (vii) #12 Pine Commercial Centre, The Pine, St. Michael, BB11103, Barbados (viii) #12 Pine Commercial Centre, The Pine, St. Michael, BB11103, Barbados (ix) 401 East Corporate Drive, Suite 200, Lewisville, Texas, 75057, USA (x) 300 First Stamford Place, Stamford, Connecticut, USA 06902 (xi) 300 First Stamford Place, Stamford, Connecticut, USA 06902 (xii) Corporation Trust Company, 1209 Orange Street, Corporate Trust Center, Wilmington, County of New Castle, Delaware, 19801, USA (xiii) Corporation Trust Company, 1209 Orange Street, Corporate Trust Center, Wilmington, County of New Castle, Delaware, 19801, USA (xiv) 21255 Califa Street, Woodland Hills, California, 91367-5021, USA (xv) 21255 Califa Street, Woodland Hills, California, 91367-5021, USA (xvi) Corporation Trust Company, 1209 Orange Street, Corporate Trust Center, Wilmington, County of New Castle, Delaware, 19801, USA (xvii) Corporation Trust Company, 1209 Orange Street, Corporate Trust Center, Wilmington, County of New Castle, Delaware, 19801, USA (xviii) 305 Madison Avenue, Morristown, New Jersey, USA, 07962 (xix) The Leadenhall Building, 122 Leadenhall Street, London, United Kingdom, EC3V 4AB (xx) The Leadenhall Building, 122 Leadenhall Street, London, United Kingdom, EC3V 4AB (xxi) The Leadenhall Building, 122 Leadenhall Street, London, United Kingdom, EC3V 4AB (xxii) Clarendon House, 2 Church Street, Hamilton, Bermuda HM 11 (xxiii) 1600 - 925 West Georgia Street, Vancouver, British Columbia, V6C 3L2, Canada (xxiv) 27 Richmond Road, Pembroke, Bermuda HM 08 (xxv) 27 Richmond Road, Pembroke, Bermuda HM 08 (xxvi) 27 Richmond Road, Pembroke, Bermuda HM 08 (xxvii) 27 Richmond Road, Pembroke, Bermuda HM 08 (xxviii) Corporation Trust Company, 1209 Orange Street, Corporate Trust Center, Wilmington, County of New Castle, Delaware, 19801, USA (xxix) 10 Ferry Street, Suite 313, Concord, New Hampshire, 03301, USA (xxx) Corporation Service Company, 251 Little Falls Drive, Wilmington, Delaware, 19808, USA (xxxi) Corporation Service Company, 251 Little Falls Drive, Wilmington, Delaware, 19808, USA For each of the Reporting Persons, a full response to Item 2(c) Present principal occupation or employment and the name, principal business and address of any corporation or other organization in which such employment is conducted is set forth in Exhibit 99.4 hereto. (i) No (ii) No (iii) No (iv) No (v) No (vi) No (vii) No (viii) No (ix) No (x) No (xi) No (xii) No (xiii) No (xiv) No (xv) No (xvi) No (xvii) No (xviii) No (xix) No (xx) No (xxi) No (xxii) No (xxiii) No (xxiv) No (xxv) No (xxvi) No (xxvii) No (xxviii) No (xxix) No (xxx) No (xxxi) No (i) No (ii) No (iii) No (iv) No (v) No (vi) No (vii) No (viii) No (ix) No (x) No (xi) No (xii) No (xiii) No (xiv) No (xv) No (xvi) No (xvii) No (xviii) No (xix) No (xx) No (xxi) No (xxii) No (xxiii) No (xxiv) No (xxv) No (xxvi) No (xxvii) No (xxviii) No (xxix) No (xxx) No (xxxi) No (i) CANADA (ii) CANADA (iii) CANADA (iv) BRITISH COLUMBIA (v) CANADA (vi) CANADA (vii) BARBADOS (viii) BARBADOS (ix) DELAWARE (x) DELAWARE (xi) CONNECTICUT (xii) DELAWARE (xiii) DELAWARE (xiv) DELAWARE (xv) CALIFORNIA (xvi) DELAWARE (xvii) DELAWARE (xviii) NEW JERSEY (xix) UNITED KINGDOM (xx) UNITED KINGDOM (xxi) UNITED KINGDOM (xxii) BERMUDA (xxiii) BRITISH COLUMBIA (xxiv) BERMUDA (xxv) BERMUDA (xxvi) BERMUDA (xxvii) BERMUDA (xxviii) DELAWARE (xxix) NEW HAMPSHIRE (xxx) DELAWARE (xxxi) DELAWARE Based on the most recent information available, the aggregate number and percentage of Shares (the securities identified by Item 1 of this Schedule 13D) that are beneficially owned by each of the Reporting Persons is set forth in boxes 11 and 13 of this Schedule 13D for each of the Reporting Persons, and such information is incorporated herein by reference. The percentage of Class A Shares beneficially owned by each of the Reporting Persons was calculated based on 188,834,386 Class A Shares outstanding as of January 31, 2026, as reported by Under Armour, Inc. The numbers of Class A Shares as to which each of the Reporting Persons has sole voting power, shared voting power, sole dispositive power and shared dispositive power is set forth in boxes 7, 8, 9 and 10, respectively, on the second part of the cover page to this Schedule 13D for each of the Reporting Persons, and such information is incorporated herein by reference. To the best knowledge of the Reporting Persons, the persons listed in Exhibit 99.5 hereto beneficially own the amounts of Class A Shares listed therein and have sole voting power and sole dispositive power with respect to such Class A Shares. Except as described in Exhibit 99.6, to the best knowledge of the Reporting Persons, none of the persons listed in Exhibit 99.4 hereto beneficially owns, or has acquired or disposed of, any Class A Shares during the last 60 days. No person is known to have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of Class A Shares held by the Reporting Persons other than each of the Reporting Persons. Not applicable. Exhibit 99.4 Directors and Executive Officers of the Reporting Persons Exhibit 99.5 Beneficial Ownership by Directors and Executive Officers of the Reporting Persons Exhibit 99.6 Transactions in the Class A Shares of the Issuer by the Reporting Persons During the Last Sixty (60) Days Exhibit 99.7 Joint Filing Agreement dated as of May 15, 2026 among the Reporting Persons V. PREM WATSA /s/ V. Prem Watsa 05/15/2026 THE SECOND 810 HOLDCO LTD. /s/ V. Prem Watsa 05/15/2026 THE SECOND 1109 HOLDCO LTD. /s/ V. Prem Watsa 05/15/2026 THE SIXTY TWO INVESTMENT COMPANY LIMITED /s/ V. Prem Watsa 05/15/2026 FAIRFAX FINANCIAL HOLDINGS LIMITED /s/ Peter Clarke 05/15/2026 FFHL GROUP LTD. /s/ V. Prem Watsa 05/15/2026 FAIRFAX (BARBADOS) INTERNATIONAL CORP. /s/ Peter Clarke 05/15/2026 WENTWORTH INSURANCE COMPANY LTD. /s/ Peter Clarke 05/15/2026 FAIRFAX (US) INC. /s/ Peter Clarke 05/15/2026 ODYSSEY GROUP HOLDINGS, INC. /s/ Peter Clarke 05/15/2026 ODYSSEY REINSURANCE COMPANY /s/ Peter Clarke 05/15/2026 HUDSON INSURANCE COMPANY /s/ Peter Clarke 05/15/2026 HUDSON EXCESS INSURANCE COMPANY /s/ Peter Clarke 05/15/2026 ZENITH NATIONAL INSURANCE CORP. /s/ Peter Clarke 05/15/2026 ZENITH INSURANCE COMPANY /s/ Peter Clarke 05/15/2026 CRUM & FORSTER HOLDINGS CORP. /s/ Peter Clarke 05/15/2026 UNITED STATES FIRE INSURANCE COMPANY /s/ Peter Clarke 05/15/2026 THE NORTH RIVER INSURANCE COMPANY /s/ Peter Clarke 05/15/2026 FAIRFAX UK HOLDINGS LIMITED /s/ Gavin Wilkinson 05/15/2026 BRIT GROUP HOLDINGS LIMITED /s/ Gavin Wilkinson 05/15/2026 BRIT INSURANCE HOLDINGS LIMITED /s/ Gavin Wilkinson 05/15/2026 BRIT REINSURANCE (BERMUDA) LIMITED /s/ Gavin Wilkinson 05/15/2026 1102952 B.C. UNLIMITED LIABILITY COMPANY /s/ Peter Clarke 05/15/2026 ALLIED WORLD ASSURANCE COMPANY HOLDINGS, LTD /s/ Peter Clarke 05/15/2026 ALLIED WORLD ASSURANCE COMPANY HOLDINGS I, LTD /s/ Peter Clarke 05/15/2026 ALLIED WORLD ASSURANCE COMPANY, LTD /s/ Peter Clarke 05/15/2026 ALLIED WORLD ASSURANCE HOLDINGS (IRELAND) LTD /s/ Peter Clarke 05/15/2026 ALLIED WORLD ASSURANCE HOLDINGS (U.S.) INC. /s/ Peter Clarke 05/15/2026 ALLIED WORLD INSURANCE COMPANY /s/ Peter Clarke 05/15/2026 AW UNDERWRITERS INC. /s/ Peter Clarke 05/15/2026 ALLIED WORLD SPECIALTY INSURANCE COMPANY /s/ Peter Clarke 05/15/2026 Power of attorney, dated March 9, 2020 (incorporated by reference to Exhibit 8 to the Schedule 13D filed by certain of the Reporting Persons with the SEC on March 9, 2020). Power of attorney, dated June 14, 2021 (incorporated by reference to Exhibit 5 to the Schedule 13D filed by certain of the Reporting Persons with the SEC on June 14, 2021).