X0202 SCHEDULE 13D/A 0001104659-24-068877 0002025889 XXXXXXXX LIVE 13 Class A ordinary shares, par value $0.0000001 per share 06/12/2026 false 0001899123 G11448100 BITDEER TECHNOLOGIES GROUP

08 Kallang Avenue Aperia Tower 1, #09-03/04 Singapore U0 339509

Tether Global Investments Fund 4420 4621 1793 Final Av. La Revolucion, Edif. Centro Corporativo Presidente Plaza, Nivel 12 San Salvador H3 00000 Daniel Woodard (212) 547-5400 McDermott Will & Schulte LLP One Vanderbilt Avenue New York NY 10017 0002025889 N Tether Global Investments Fund, S.I.C.A.F., S.A. WC N H3 0.00 37729510.00 0.00 37729510.00 37729510.00 N 19.7 CO Note in relation to Items 8, 10 and 11: Includes 37,729,510 Class A ordinary shares, par value $0.0000001 per share ("Class A Shares") of Bitdeer Technologies Group held by Tether International, S.A. de C.V., a wholly owned subsidiary of Tether Global Investments Fund, S.I.C.A.F., S.A. Note in relation to Item 13: This percentage is calculated based upon 191,152,162 Class A Shares outstanding on December 31, 2025, as reported in the Issuer's Annual Report of Form 20-F filed with the Securities and Exchange Commission on April 30, 2026. Y Tether Investments, S.A. de C.V. WC N H3 0.00 0.00 0.00 0.00 0.00 N 0 CO Y Tether International, S.A. de C.V. WC N H3 0.00 37729510.00 0.00 37729510.00 37729510.00 N 19.7 CO Note in relation to Item 13: This percentage is calculated based upon 191,152,162 Class A Shares outstanding on December 31, 2025, as reported in the Issuer's Annual Report of Form 20-F filed with the Securities and Exchange Commission on April 30, 2026. Y Giancarlo Devasini WC N L6 0.00 37729510.00 0.00 37729510.00 37729510.00 N 19.7 IN Note in relation to Items 8, 10 and 11: Includes 37,729,510 Class A Shares held by Tether International, S.A. de C.V., a wholly owned subsidiary of Tether Global Investments Fund, S.I.C.A.F., S.A. Mr. Devasini has a greater than 50% voting interest in Tether Global Investments Fund, S.I.C.A.F., S.A. The reporting person disclaims beneficial ownership of these shares except to the extent of the reporting person's pecuniary interest. Note in relation to Item 13: This percentage is calculated based upon 191,152,162 Class A Shares outstanding on December 31, 2025, as reported in the Issuer's Annual Report of Form 20-F filed with the Securities and Exchange Commission on April 30, 2026. Class A ordinary shares, par value $0.0000001 per share BITDEER TECHNOLOGIES GROUP 08 Kallang Avenue Aperia Tower 1, #09-03/04 Singapore U0 339509 This statement on Schedule 13D amends the Schedule 13D of Tether Holdings Limited, a British Virgin Islands business company, Tether International Limited, a British Virgin Islands business company, Ludovicus Jan Van der Velde and Giancarlo Devasini that was originally filed with the Securities and Exchange Commission on June 6, 2024, as amended by Amendment No. 1 filed on August 8, 2024, Amendment No. 2 filed on September 3, 2024, Amendment No. 3 filed on November 7, 2024, Amendment No. 4 filed on January 22, 2025, Amendment No. 5 filed on March 17, 2025, Amendment No. 6 filed on April 8, 2025, Amendment No. 7 filed on April 15, 2025, Amendment No. 8 filed on April 23, 2025, Amendment No. 9 filed on November 10, 2025, Amendment No. 10 filed on November 25, 2025, Amendment No. 11 filed on February 20, 2026 and Amendment No. 12 filed on June 16, 2026 (as amended, the "Schedule 13D") with respect to the Class A ordinary shares, par value $0.0000001 per share ("Class A Shares") of Bitdeer Technologies Group, an exempted company incorporated in the Cayman Islands (the "Issuer"). This amendment to the Schedule 13D is being filed by Tether Global Investments Fund, S.I.C.A.F., S.A. (f/k/a Tether Holdings, S.A. de C.V. and Tether Holdings Limited), an El Salvador entity, Tether Investments, S.A. de C.V. (f/k/a Tether Investments Limited), an El Salvador entity ("Tether Investments"), Tether International, S.A. de C.V., an El Salvador entity, and Giancarlo Devasini (collectively, the "Reporting Persons") and constitutes Amendment No.13 to the Schedule 13D. Capitalized terms used but not defined herein have the meanings given to such terms in the Schedule 13D. This Amendment No. 13 to Schedule 13D is being filed solely to correct an inadvertent understatement of the number of Class A Shares that Tether Investments transferred to Tether International, S.A. de C.V. as described in Item 4 of Amendment No. 12 to Schedule 13D filed by the Reporting Persons on June 16, 2026. Except as set forth herein, the Schedule 13D is unmodified. Effective on June 12, 2026, Tether Investments transferred 37,729,510 Class A Shares to Tether International, S.A. de C.V. (the "Transfer"). The Transfer resulted in no change in the aggregate number of Class A Shares beneficially owned by the Reporting Persons. The Reporting Persons beneficially own an aggregate of 37,729,510 of the Issuer's Class A Shares, representing 19.7% of the outstanding Class A Shares. This percentage is calculated based upon 191,152,162 Class A Shares outstanding on December 31, 2025, as reported in the Issuer's Annual Report of Form 20-F filed with the Securities and Exchange Commission on April 30, 2026. Each of the Reporting Persons (other than Tether Investments) has shared voting and dispositive power with respect to 37,729,510 of the Issuer's Class A Shares. Schedule B sets forth the transactions in the Class A Shares (other than the Transfer) effected by the Reporting Persons in the last 60 days. None. Not applicable. Schedule A - Executive Officers and Directors Schedule B - Transactions in Class A Shares Exhibit 1 - Agreement of filing persons relating to filing of joint statement per Rule 13d-1(k). Tether Global Investments Fund, S.I.C.A.F., S.A. /s/ Omar Rossi 06/30/2026 Tether Investments, S.A. de C.V. /s/ Giancarlo Devasini 06/30/2026 Tether International, S.A. de C.V. /s/ Giancarlo Devasini 06/30/2026 Giancarlo Devasini /s/ Giancarlo Devasini 06/30/2026