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    <ACCEPTANCE-DATETIME>20231222092828
    ACCESSION NUMBER:		0000350894-23-000110
    CONFORMED SUBMISSION TYPE:	8-K
    PUBLIC DOCUMENT COUNT:		30
    CONFORMED PERIOD OF REPORT:	20231219
    ITEM INFORMATION:		Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers: Compensatory Arrangements of Certain Officers
    ITEM INFORMATION:		Financial Statements and Exhibits
    FILED AS OF DATE:		20231222
    DATE AS OF CHANGE:		20231222

    FILER:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			SEI INVESTMENTS CO
    		CENTRAL INDEX KEY:			0000350894
    		STANDARD INDUSTRIAL CLASSIFICATION:	SECURITY BROKERS, DEALERS & FLOTATION COMPANIES [6211]
    		ORGANIZATION NAME:           	02 Finance
    		IRS NUMBER:				231707341
    		STATE OF INCORPORATION:			PA
    		FISCAL YEAR END:			1231

    	FILING VALUES:
    		FORM TYPE:		8-K
    		SEC ACT:		1934 Act
    		SEC FILE NUMBER:	000-10200
    		FILM NUMBER:		231507475

    	BUSINESS ADDRESS:
    		STREET 1:		1 FREEDOM VALLEY DRIVE
    		CITY:			OAKS
    		STATE:			PA
    		ZIP:			19456-1100
    		BUSINESS PHONE:		6106761000

    	MAIL ADDRESS:
    		STREET 1:		1 FREEDOM VALLEY DRIVE
    		CITY:			OAKS
    		STATE:			PA
    		ZIP:			19456-1100

    	FORMER COMPANY:
    		FORMER CONFORMED NAME:	SEI INVESTMENT CO
    		DATE OF NAME CHANGE:	20040806

    	FORMER COMPANY:
    		FORMER CONFORMED NAME:	SEI CORP
    		DATE OF NAME CHANGE:	19920703
    </SEC-HEADER>
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    <SEQUENCE>1
    <FILENAME>seic-20231219.htm
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    Document 1 - file: seic-20231219.htm

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    <DOCUMENT>
    <TYPE>EX-99.1
    <SEQUENCE>2
    <FILENAME>ex991withrowseparationag.htm
    <DESCRIPTION>SEPARATION AGREEMENT RELATED TO WAYNE WITHROW DATED DECEMBER 19, 2023
    <TEXT>
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    <SEQUENCE>30
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