ACGL: Other company developments

ITEM 8.01 Other Events . On June 2, 2026, Arch Capital Group Ltd. (“ACGL”) issued a press release announcing that its wholly-owned subsidiaries, Arch Capital Group (U.S.) Inc. (“Arch Capital Group (U.S.)”) and Arch Capital Finance LLC (“Arch Capital Finance”), commenced cash tender offers to purchase (the “Tender Offers”) for a combined aggregate purchase price of up to $350 million (i) Arch Capital Group (U.S.)’s outstanding 5.144% Senior Notes due 2043, and (ii) Arch Capital Finance’s outstanding 5.031% Senior Notes due 2046. A copy of the press release announcing the Tender Offers is attached hereto as Exhibit 99.1 and incorporated by reference herein. ITEM 9.01 Financial Statements and Exhibits . (d): The following exhibits are being filed herewith. EXHIBIT NO. DESCRIPTION 99.1 Press release dated June 2, 2026 104 Cover Page Interactive Data File (embedded within the Inline XBRL document) 2 SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ARCH CAPITAL GROUP LTD. Date: June 2, 2026 By: /s/ François Morin Name: François Morin Title: Executive Vice President, Chief Financial Officer and Treasurer 3