    <SEC-DOCUMENT>0001144204-19-027563-index.html : 20190522
    <SEC-HEADER>0001144204-19-027563.hdr.sgml : 20190522
    <ACCEPTANCE-DATETIME>20190521191942
    ACCESSION NUMBER:		0001144204-19-027563
    CONFORMED SUBMISSION TYPE:	S-1/A
    PUBLIC DOCUMENT COUNT:		16
    FILED AS OF DATE:		20190522
    DATE AS OF CHANGE:		20190521

    FILER:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			SeqLL, Inc.
    		CENTRAL INDEX KEY:			0001605888
    		STANDARD INDUSTRIAL CLASSIFICATION:	LABORATORY ANALYTICAL INSTRUMENTS [3826]
    		IRS NUMBER:				465319744
    		STATE OF INCORPORATION:			DE
    		FISCAL YEAR END:			1231

    	FILING VALUES:
    		FORM TYPE:		S-1/A
    		SEC ACT:		1933 Act
    		SEC FILE NUMBER:	333-230985
    		FILM NUMBER:		19843698

    	BUSINESS ADDRESS:
    		STREET 1:		317 NEW BOSTON STREET
    		STREET 2:		SUITE 210
    		CITY:			WOBURN
    		STATE:			MA
    		ZIP:			01801
    		BUSINESS PHONE:		(781) 817-3755

    	MAIL ADDRESS:
    		STREET 1:		317 NEW BOSTON STREET
    		STREET 2:		SUITE 210
    		CITY:			WOBURN
    		STATE:			MA
    		ZIP:			01801
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    <DOCUMENT>
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    <SEQUENCE>1
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    Document 1 - file: tv519463-s1a.htm

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    <TYPE>EX-1.1
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    <FILENAME>tv519463_ex1-1.htm
    <DESCRIPTION>EXHIBIT 1.1
    <TEXT>
    Document 2 - file: tv519463_ex1-1.htm

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    <DOCUMENT>
    <TYPE>EX-3.3
    <SEQUENCE>3
    <FILENAME>tv519463_ex3-3.htm
    <DESCRIPTION>EXHIBIT 3.3
    <TEXT>
    Document 3 - file: tv519463_ex3-3.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-4.1
    <SEQUENCE>4
    <FILENAME>tv519463_ex4-1.htm
    <DESCRIPTION>EXHIBIT 4.1
    <TEXT>
    Document 4 - file: tv519463_ex4-1.htm

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    <DOCUMENT>
    <TYPE>EX-5.1
    <SEQUENCE>5
    <FILENAME>tv519463_ex5-1.htm
    <DESCRIPTION>EXHIBIT 5.1
    <TEXT>
    Document 5 - file: tv519463_ex5-1.htm

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    <DOCUMENT>
    <TYPE>EX-23.1
    <SEQUENCE>6
    <FILENAME>tv519463_ex23-1.htm
    <DESCRIPTION>EXHIBIT 23.1
    <TEXT>
    Document 6 - file: tv519463_ex23-1.htm

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    <FILENAME>lg_seqll-02.jpg
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    Document 8 - file: tv507078_chrt-line.jpg

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    Document 10 - file: tv507078_chrt-bar2.jpg

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    <FILENAME>tv507078_chrt-flow.jpg
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    Document 12 - file: tv507078_chrt-flow.jpg

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    <FILENAME>tv507078_img-tsms.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 13 - file: tv507078_img-tsms.jpg

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    <SEQUENCE>14
    <FILENAME>tv507078_ex5-1img.jpg
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    Document 14 - file: tv507078_ex5-1img.jpg

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    <TEXT>
    Document 15 - file: tv519463_ex4-1img01.jpg

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    <SEQUENCE>16
    <FILENAME>tv519463_ex4-1img02.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 16 - file: tv519463_ex4-1img02.jpg

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