<SEC-DOCUMENT>0001140361-25-047051.txt : 20251231
<SEC-HEADER>0001140361-25-047051.hdr.sgml : 20251231
<ACCEPTANCE-DATETIME>20251231155214
ACCESSION NUMBER:		0001140361-25-047051
CONFORMED SUBMISSION TYPE:	3
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20251221
FILED AS OF DATE:		20251231
DATE AS OF CHANGE:		20251231

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MASSACHUSETTS MUTUAL LIFE INSURANCE CO
		CENTRAL INDEX KEY:			0000225602
		ORGANIZATION NAME:           	
		STATE OF INCORPORATION:			MA
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38103
		FILM NUMBER:		251617367

	BUSINESS ADDRESS:	
		STREET 1:		1295 STATE STREET
		CITY:			SPRINGFIELD
		STATE:			MA
		ZIP:			01111
		BUSINESS PHONE:		4137448411

	MAIL ADDRESS:	
		STREET 1:		1295 STATE STREET
		CITY:			SPRINGFIELD
		STATE:			MA
		ZIP:			01111

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			JANUS HENDERSON GROUP PLC
		CENTRAL INDEX KEY:			0001274173
		STANDARD INDUSTRIAL CLASSIFICATION:	INVESTMENT ADVICE [6282]
		ORGANIZATION NAME:           	02 Finance
		EIN:				000000000
		STATE OF INCORPORATION:			Y9
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		201 BISHOPSGATE
		CITY:			LONDON
		STATE:			X0
		ZIP:			EC2M 3AE
		BUSINESS PHONE:		442078181818

	MAIL ADDRESS:	
		STREET 1:		201 BISHOPSGATE
		CITY:			LONDON
		STATE:			X0
		ZIP:			EC2M 3AE

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	HENDERSON GROUP PLC
		DATE OF NAME CHANGE:	20050511

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	HHG PLC
		DATE OF NAME CHANGE:	20031223
</SEC-HEADER>
<DOCUMENT>
<TYPE>3
<SEQUENCE>1
<FILENAME>form3.xml
<DESCRIPTION>FORM 3
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0206</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2025-12-21</periodOfReport>

    <noSecuritiesOwned>1</noSecuritiesOwned>

    <issuer>
        <issuerCik>0001274173</issuerCik>
        <issuerName>JANUS HENDERSON GROUP PLC</issuerName>
        <issuerTradingSymbol>JHG</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0000225602</rptOwnerCik>
            <rptOwnerName>MASSACHUSETTS MUTUAL LIFE INSURANCE CO</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1295 STATE STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SPRINGFIELD</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>01111</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isOther>true</isOther>
            <otherText>See Remarks</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <remarks>The Reporting Person may be deemed to be a member of a group for purposes of Rule 13d-5 of the Securities Exchange Act of 1934, as amended, that beneficially owns more than ten percent of the outstanding Issuer ordinary shares.  The filing of this report shall not be deemed to be an admission that the Reporting Person is a member of any such group, and the Reporting Person disclaims beneficial ownership of any securities beneficially owned by such other members.</remarks>

    <ownerSignature>
        <signatureName>MASSACHUSETTS MUTUAL LIFE INSURANCE COMPANY, By: /s/ Jaime Genua, Name: Jaime Genua, Title: Assistant Secretary</signatureName>
        <signatureDate>2025-12-31</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
