and Exhibit 99.1 hereto shall not be deemed “filed” for purposes of Section 18 of the Securities and Exchange Act of 1934, as amended, nor shall it be deemed incorporated by reference in any filing with the Securities and Exchange Commission, except as shall be expressly provided by specific reference in such filing.

Other Events. On May 27, 2026, the Board of Directors of the Company declared a dividend of $0.52 per share. The cash dividend will be payable to shareholders of record on June 8, 2026, with a payment date of June 16, 2026. A copy of the press release is furnished as Exhibit 99.1 and incorporated in this

and Exhibit 99.1 hereto shall not be deemed “filed” for purposes of Section 18 of the Securities and Exchange Act of 1934, as amended, nor shall it be deemed incorporated by reference in any filing with the Securities and Exchange Commission, except as shall be expressly provided by specific reference in such filing.

and Exhibit 99.1 hereof shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, nor shall it be deemed incorporated by reference in any filing with the Securities and Exchange Commission, except as shall be expressly provided by specific reference in such filing. This Current Report on Form 8-K and the Exhibit hereto contains forward-looking statements within the meaning or the rules and regulations of the Securities and Exchange Commission.…

Results of Operations and Financial Condition. On Wednesday, January 28, 2026, SEI Investments Company (the "Company") issued a press release announcing its financial and operating results for the fourth quarter ended December 31, 2025. A copy of the press release is furnished as Exhibit 99.1 and incorporated in this

CEO — Ryan Hicke: The filing discloses a new employment agreement and compensation terms for the sitting CEO, not a departure, appointment, or board election.

Executive Chairman — Alfred P. West, Jr.: The founder and long-serving Executive Chairman is resigning from his officer and director roles but transitioning to a non-voting Chairman Emeritus position, with a named successor appointed, indicating an orderly succession rather than a sudden loss of leadership.

Other Events. Also on December 12, 2025, the Board of Directors of SEI Investments Company declared a dividend of $0.52 per share. The cash dividend will be payable to shareholders of record on December 29, 2025 with a payment date of January 12, 2026.

Other Events. On October 20, 2025, the Board of Directors of SEI Investments Company approved an increase in its stock repurchase program by an additional $650 million, increasing the available authorization under the program to approximately $773 million. A copy of the press release is furnished as Exhibit 99.1 and incorporated in this

Results of Operations and Financial Condition. On Wednesday, October 22, 2025, SEI Investments Company (the "Company") issued a press release announcing its financial and operating results for the third quarter ended September 30, 2025. A copy of the press release is furnished as Exhibit 99.1 and incorporated in this

and Exhibit 99.1 hereof shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, nor shall it be deemed incorporated by reference in any filing with the Securities and Exchange Commission, except as shall be expressly provided by specific reference in such filing. This Current Report on Form 8-K and the Exhibit hereto contains forward-looking statements within the meaning or the rules and regulations of the Securities and Exchange Commission.…

Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant. On Monday, August 18, 2025, SEI Investments Company (the "Company") entered into a Credit Agreement, dated as of such date, among the Company, U.S. Bank National Association, as administrative agent, Wells Fargo Bank, National Association, as syndication agent, Bank of America, N.A., JP Morgan Chase Bank, N.A., CIBC Bank USA and Citizens Bank, N.A., each as documentation agent, a…

Entry into a Material Definitive Agreement. The information set forth under item 2.03, “Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant,” is incorporated herein by reference.

and Exhibit 99.1 hereto shall not be deemed “filed” for purposes of Section 18 of the Securities and Exchange Act of 1934, as amended, nor shall it be deemed incorporated by reference in any filing with the Securities and Exchange Commission, except as shall be expressly provided by specific reference in such filing.

Director — Stephanie D. Miller: The filing reports the resignation of a director and the immediate appointment of two new directors to fill the vacancies, which is a standard board composition change rather than a loss of senior executive management.

and Exhibit 99.1 hereof shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, nor shall it be deemed incorporated by reference in any filing with the Securities and Exchange Commission, except as shall be expressly provided by specific reference in such filing. This Current Report on Form 8-K and the Exhibits hereto may contain forward looking statements within the meaning or the rules and regulations of the Securities and Exchange Commissi…

Other Events. On May 28, 2025, the Board of Directors of the Company declared a dividend of $0.49 per share. The cash dividend will be payable to shareholders of record on June 9, 2025, with a payment date of June 17, 2025. A copy of the press release is furnished as Exhibit 99.1 and incorporated in this

and Exhibit 99.1 hereto shall not be deemed “filed” for purposes of Section 18 of the Securities and Exchange Act of 1934, as amended, nor shall it be deemed incorporated by reference in any filing with the Securities and Exchange Commission, except as shall be expressly provided by specific reference in such filing.

Other Events. On March 18, 2025, the Board of Directors of SEI Investments Company approved an increase in its stock repurchase program by an additional $500 million, increasing the available authorization under the program to approximately $556 million. A copy of the press release is furnished as Exhibit 99.1 and incorporated in this

CFO — Sean J. Denham: The filing announces an internal executive expanding his existing CFO role to also serve as COO, which is a consolidation of leadership rather than a departure.

Results of Operations and Financial Condition. On Wednesday, January 29, 2025, SEI Investments Company (the "Company") issued a press release announcing its financial and operating results for the fourth quarter ended December 31, 2024. A copy of the press release is furnished as Exhibit 99.1 and incorporated in this

and Exhibit 99.1 hereof shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, nor shall it be deemed incorporated by reference in any filing with the Securities and Exchange Commission, except as shall be expressly provided by specific reference in such filing. This Amendment No. 1 to the Current Report on Form 8-K and the Exhibits hereto may contain forward looking statements within the meaning or the rules and regulations of the Securitie…

and Exhibit 99.1 hereof shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, nor shall it be deemed incorporated by reference in any filing with the Securities and Exchange Commission, except as shall be expressly provided by specific reference in such filing. This Current Report on Form 8-K and the Exhibits hereto may contain forward looking statements within the meaning or the rules and regulations of the Securities and Exchange Commissi…

Other Events. On December 12, 2024, the Board of Directors of SEI Investments Company declared a dividend of $0.49 per share. The cash dividend will be payable to shareholders of record on December 27, 2024 with a payment date of January 8, 2025. A copy of the press release is furnished as Exhibit 99.1 and incorporated in this

Results of Operations and Financial Condition. On Wednesday, October 23, 2024, SEI Investments Company (the "Company") issued a press release announcing its financial and operating results for the third quarter ended September 30, 2024. A copy of the press release is furnished as Exhibit 99.1 and incorporated in this