<SEC-DOCUMENT>0001104659-17-060884-index.html : 20171004
<SEC-HEADER>0001104659-17-060884.hdr.sgml : 20171004
<ACCEPTANCE-DATETIME>20171004165622
ACCESSION NUMBER:		0001104659-17-060884
CONFORMED SUBMISSION TYPE:	3
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20171004
FILED AS OF DATE:		20171004
DATE AS OF CHANGE:		20171004

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Hadley Harbor Master Investors (Cayman) L.P.
		CENTRAL INDEX KEY:			0001641080
		STATE OF INCORPORATION:			E9
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38223
		FILM NUMBER:		171122270

	BUSINESS ADDRESS:	
		STREET 1:		ELIAN FIDUCIARY SERVICES (CAYMAN) LTD
		STREET 2:		89 NEXUS WAY, CAMANA BAY
		CITY:			GRAND CAYMAN
		STATE:			E9
		ZIP:			KY1-9007
		BUSINESS PHONE:		617-790-7163

	MAIL ADDRESS:	
		STREET 1:		ELIAN FIDUCIARY SERVICES (CAYMAN) LTD
		STREET 2:		89 NEXUS WAY, CAMANA BAY
		CITY:			GRAND CAYMAN
		STATE:			E9
		ZIP:			KY1-9007

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			RHYTHM PHARMACEUTICALS, INC.
		CENTRAL INDEX KEY:			0001649904
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				462159271
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		500 BOYLSTON STREET
		STREET 2:		11TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02116
		BUSINESS PHONE:		857-264-4280

	MAIL ADDRESS:	
		STREET 1:		500 BOYLSTON STREET
		STREET 2:		11TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02116

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	RHYTHM METABOLIC, INC.
		DATE OF NAME CHANGE:	20150803
</SEC-HEADER>
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Document 1 - RAW XML: a3.xml
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