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<ACCEPTANCE-DATETIME>20171106062005
ACCESSION NUMBER:		0001193125-17-333514
CONFORMED SUBMISSION TYPE:	S-1/A
PUBLIC DOCUMENT COUNT:		19
FILED AS OF DATE:		20171106
DATE AS OF CHANGE:		20171106

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Arsanis, Inc.
		CENTRAL INDEX KEY:			0001501697
		STANDARD INDUSTRIAL CLASSIFICATION:	BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES) [2836]
		IRS NUMBER:				273181608
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		S-1/A
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	333-221050
		FILM NUMBER:		171178161

	BUSINESS ADDRESS:	
		STREET 1:		890 WINTER STREET, SUITE 230
		CITY:			WALTHAM
		STATE:			MA
		ZIP:			02451
		BUSINESS PHONE:		781-819-5704

	MAIL ADDRESS:	
		STREET 1:		890 WINTER STREET, SUITE 230
		CITY:			WALTHAM
		STATE:			MA
		ZIP:			02451
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