<SEC-DOCUMENT>0001274173-24-000067-index.html : 20240411
<SEC-HEADER>0001274173-24-000067.hdr.sgml : 20240411
<ACCEPTANCE-DATETIME>20240411095146
ACCESSION NUMBER:		0001274173-24-000067
CONFORMED SUBMISSION TYPE:	SC 13G
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20240411
DATE AS OF CHANGE:		20240411

SUBJECT COMPANY:	

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ARCA biopharma, Inc.
		CENTRAL INDEX KEY:			0000907654
		STANDARD INDUSTRIAL CLASSIFICATION:	IN VITRO & IN VIVO DIAGNOSTIC SUBSTANCES [2835]
		ORGANIZATION NAME:           	03 Life Sciences
		IRS NUMBER:				363855489
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SC 13G
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	005-51477
		FILM NUMBER:		24837330

	BUSINESS ADDRESS:	
		STREET 1:		10170 CHURCH RANCH WAY
		STREET 2:		SUITE 100
		CITY:			WESTMINSTER
		STATE:			CO
		ZIP:			80021
		BUSINESS PHONE:		7209402200

	MAIL ADDRESS:	
		STREET 1:		10170 CHURCH RANCH WAY
		STREET 2:		SUITE 100
		CITY:			WESTMINSTER
		STATE:			CO
		ZIP:			80021

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	NUVELO INC
		DATE OF NAME CHANGE:	20030203

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	HYSEQ INC
		DATE OF NAME CHANGE:	19970610

FILED BY:		

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

	FILING VALUES:
		FORM TYPE:		SC 13G

	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>SC 13G
<SEQUENCE>1
<FILENAME>JHBIFArcaBiopharma040324.txt
<DESCRIPTION>JANUS HENDERSON GROUP PLC OWNS 7.4% OF ARCA BIOPHARMA, INC
<TEXT>
Document 1 - file: JHBIFArcaBiopharma040324.txt

</DOCUMENT>
</SEC-DOCUMENT>