X0609 4 2026-05-08 0 0001073404 GERDAU S.A. GGB GGBR 0002120774 Da Cunha Gustavo Werneck true AVENUE DOUTORA RUTH DE CARDOSO, 8501 8TH FLOOR, PINHEIROS SAO PAULO SAO PAULO D5 05425-070 0 1 0 0 CEO and Board Member 0 Preferred shares 2026-05-08 4 A 0 432774 0 A 432854 D Preferred shares 2026-05-08 4 S 0 432854 4.87 D 0 D Restricted Stock Units 3.84 2027-02-12 2027-02-12 Preferred shares 86455 86455 D Restricted Stock Units 3.73 2027-09-01 2027-09-01 Preferred shares 152887 152887 D Restricted Stock Units 3.6 2028-02-12 2028-02-12 Preferred shares 92024 92024 D Restricted Stock Units 4.1 2029-02-12 2029-02-12 Preferred shares 86598 86598 D The shares were received by the reporting person pursuant to the settlement of a compensation arrangement between the issuer and the reporting person. The price is denominated in Brazilian reais and has been translated into U.S. dollars at the May 8, 2026 selling rate of R$4.8999 per US$1.00, as reported by the Central Bank of Brazil. The price reported in Column 4 is a weighted average price. There shares were sold in multiple transactions at prices ranging from $4.86 to $4.90, inclusive. The price is denominated in Brazilian reais and has been translated into U.S. dollars at the April 9, 2026 selling rate of R$5.0821 per US$1.00, as reported by the Central Bank of Brazil. /s/ Gustavo Werneck Da Cunha 2026-05-12