<SEC-DOCUMENT>0001193125-20-197435-index.html : 20200723
<SEC-HEADER>0001193125-20-197435.hdr.sgml : 20200723
<ACCEPTANCE-DATETIME>20200723064832
ACCESSION NUMBER:		0001193125-20-197435
CONFORMED SUBMISSION TYPE:	S-1/A
PUBLIC DOCUMENT COUNT:		43
FILED AS OF DATE:		20200723
DATE AS OF CHANGE:		20200723

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Annexon, Inc.
		CENTRAL INDEX KEY:			0001528115
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				275414423
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		S-1/A
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	333-239647
		FILM NUMBER:		201042698

	BUSINESS ADDRESS:	
		STREET 1:		180 KIMBALL WAY
		STREET 2:		SUITE 200
		CITY:			SOUTH SAN FRANCISCO
		STATE:			CA
		ZIP:			94080
		BUSINESS PHONE:		(650)-822-5500

	MAIL ADDRESS:	
		STREET 1:		180 KIMBALL WAY
		STREET 2:		SUITE 200
		CITY:			SOUTH SAN FRANCISCO
		STATE:			CA
		ZIP:			94080
</SEC-HEADER>
<DOCUMENT>
<TYPE>S-1/A
<SEQUENCE>1
<FILENAME>d773514ds1a.htm
<DESCRIPTION>S-1/A
<TEXT>
Document 1 - file: d773514ds1a.htm
</DOCUMENT> <DOCUMENT> <TYPE>EX-5.1 <SEQUENCE>2 <FILENAME>d773514dex51.htm <DESCRIPTION>EX-5.1 <TEXT> Document 2 - file: d773514dex51.htm
</DOCUMENT> <DOCUMENT> <TYPE>EX-10.5.(A) <SEQUENCE>3 <FILENAME>d773514dex105a.htm <DESCRIPTION>EX-10.5.(A) <TEXT> Document 3 - file: d773514dex105a.htm
</DOCUMENT> <DOCUMENT> <TYPE>EX-10.6 <SEQUENCE>4 <FILENAME>d773514dex106.htm <DESCRIPTION>EX-10.6 <TEXT> Document 4 - file: d773514dex106.htm
</DOCUMENT> <DOCUMENT> <TYPE>EX-23.1 <SEQUENCE>5 <FILENAME>d773514dex231.htm <DESCRIPTION>EX-23.1 <TEXT> Document 5 - file: d773514dex231.htm
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>6 <FILENAME>g773514g02e84.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 6 - file: g773514g02e84.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>7 <FILENAME>g773514g02r42.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 7 - file: g773514g02r42.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>8 <FILENAME>g773514g09l31.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 8 - file: g773514g09l31.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>9 <FILENAME>g773514g10j85.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 9 - file: g773514g10j85.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>10 <FILENAME>g773514g16w09.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 10 - file: g773514g16w09.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>11 <FILENAME>g773514g18a54.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 11 - file: g773514g18a54.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>12 <FILENAME>g773514g20t78.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 12 - file: g773514g20t78.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>13 <FILENAME>g773514g21m00.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 13 - file: g773514g21m00.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>14 <FILENAME>g773514g21m47.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 14 - file: g773514g21m47.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>15 <FILENAME>g773514g22x55.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 15 - file: g773514g22x55.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>16 <FILENAME>g773514g23r02.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 16 - file: g773514g23r02.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>17 <FILENAME>g773514g25h63.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 17 - file: g773514g25h63.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>18 <FILENAME>g773514g26o17.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 18 - file: g773514g26o17.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>19 <FILENAME>g773514g28x11.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 19 - file: g773514g28x11.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>20 <FILENAME>g773514g28y21.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 20 - file: g773514g28y21.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>21 <FILENAME>g773514g32p90.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 21 - file: g773514g32p90.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>22 <FILENAME>g773514g33c68.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 22 - file: g773514g33c68.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>23 <FILENAME>g773514g34v86.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 23 - file: g773514g34v86.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>24 <FILENAME>g773514g35y96.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 24 - file: g773514g35y96.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>25 <FILENAME>g773514g36c17.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 25 - file: g773514g36c17.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>26 <FILENAME>g773514g36m63.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 26 - file: g773514g36m63.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>27 <FILENAME>g773514g37x35.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 27 - file: g773514g37x35.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>28 <FILENAME>g773514g43r37.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 28 - file: g773514g43r37.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>29 <FILENAME>g773514g45j64.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 29 - file: g773514g45j64.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>30 <FILENAME>g773514g52p85.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 30 - file: g773514g52p85.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>31 <FILENAME>g773514g54i19.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 31 - file: g773514g54i19.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>32 <FILENAME>g773514g54u14.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 32 - file: g773514g54u14.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>33 <FILENAME>g773514g75k69.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 33 - file: g773514g75k69.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>34 <FILENAME>g773514g82q36.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 34 - file: g773514g82q36.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>35 <FILENAME>g773514g88d44.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 35 - file: g773514g88d44.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>36 <FILENAME>g773514g89g55.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 36 - file: g773514g89g55.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>37 <FILENAME>g773514g90w00.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 37 - file: g773514g90w00.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>38 <FILENAME>g773514g91c19.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 38 - file: g773514g91c19.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>39 <FILENAME>g773514g93e09.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 39 - file: g773514g93e09.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>40 <FILENAME>g773514g93s80.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 40 - file: g773514g93s80.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>41 <FILENAME>g773514g98f32.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 41 - file: g773514g98f32.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>42 <FILENAME>g773539v1_page1.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 42 - file: g773539v1_page1.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>43 <FILENAME>g773539v2.jpg <DESCRIPTION>GRAPHIC <TEXT> Document 43 - file: g773539v2.jpg
</DOCUMENT> </SEC-DOCUMENT>