<SEC-DOCUMENT>0001564590-18-005038-index.html : 20180309
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<ACCEPTANCE-DATETIME>20180309081340
ACCESSION NUMBER:		0001564590-18-005038
CONFORMED SUBMISSION TYPE:	10-K
PUBLIC DOCUMENT COUNT:		15
CONFORMED PERIOD OF REPORT:	20171231
FILED AS OF DATE:		20180309
DATE AS OF CHANGE:		20180309

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:		10-K
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38295
		FILM NUMBER:		18678503

	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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Document 1 - file: asns-10k_20171231.htm

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Document 2 - file: asns-ex1037_392.htm

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Document 3 - file: asns-ex231_447.htm

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<DESCRIPTION>EX-31.1
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Document 4 - file: asns-ex311_468.htm

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