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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 HzIXnQ3890Hvjd7/D78bXHeb0A1oMdFgBatlDNUTXWQPCuSkol9+2cWYWALENPMs
 NYqW4ZRRQ+HmagchTg3WGw==

<SEC-DOCUMENT>9999999995-09-001362.txt : 20090511
<SEC-HEADER>9999999995-09-001362.hdr.sgml : 20090511
<ACCEPTANCE-DATETIME>20090511001519
ACCESSION NUMBER:		9999999995-09-001362
CONFORMED SUBMISSION TYPE:	EFFECT
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20090508
DATE AS OF CHANGE:		20090511
EFFECTIVENESS DATE:		20090508

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			JANUS INVESTMENT FUND
		CENTRAL INDEX KEY:			0000277751
		IRS NUMBER:				840592523
		STATE OF INCORPORATION:			MA
		FISCAL YEAR END:			1031

	FILING VALUES:
		FORM TYPE:		EFFECT
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	333-158035
		FILM NUMBER:		09812543

	BUSINESS ADDRESS:	
		STREET 1:		151 DETROIT STREET
		CITY:			DENVER
		STATE:			CO
		ZIP:			80206
		BUSINESS PHONE:		3033333863

	MAIL ADDRESS:	
		STREET 1:		151 DETROIT STREET
		CITY:			DENVER
		STATE:			CO
		ZIP:			80206

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	JANUS FUND /MD/
		DATE OF NAME CHANGE:	19870701
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CENTRAL INDEX KEY:			0000277751
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<TARGET-DATA>
CENTRAL INDEX KEY:			0001110822
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<SERIES-NAME>Janus Adviser Mid Cap Growth Fund
<CLASS-CONTRACT>
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<ACQUIRING-DATA>
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<SERIES>
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<SERIES>
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<SERIES-NAME>Janus Adviser Mid Cap Growth Fund
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<TARGET-DATA>
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<SERIES>
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<CLASS-CONTRACT>
<CLASS-CONTRACT-ID>C000029132
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<TYPE>EFFECT
<SEQUENCE>1
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