SC 13G 1 tm2026968d1_sc13g.htm SCHEDULE 13G

 

 

 

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C.  20549

 

SCHEDULE 13G*/

(Rule 13d-102)

 

 

Annexon, Inc.

 

(Name of Issuer)

 

 

Common stock

 

 (Title of Class of Securities)

 

  

03589W102

 

 (CUSIP Number)

 

  

July 28, 2020

 

 Date of Event Which Requires Filing of the Statement

 

 

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

 

¨ Rule 13d-1(b)
x Rule 13d-1(c)
¨ Rule 13d-1(d)

 

  

 

*/ The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page.

 

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes). 

 

 

 

 

 

 

 1.

NAME OF REPORTING PERSON

 

Citadel Advisors LLC

 2.

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

 

(a) ¨

(b) ¨

 3.

SEC USE ONLY

 

 4.

 

CITIZENSHIP OR PLACE OF ORGANIZATION

 

Delaware

NUMBER OF

SHARES

BENEFICIALLY

OWNED BY

EACH

REPORTING

PERSON

WITH 

5.

SOLE VOTING POWER

 

0 

6.

SHARED VOTING POWER

 

2,120,333 shares 

7.

SOLE DISPOSITIVE POWER

 

0 

8.

SHARED DISPOSITIVE POWER

 

See Row 6 above

 9.

AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 

See Row 6 above

 10.

CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES ¨

 

 11.

PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

 

5.5%1

 12.

 

TYPE OF REPORTING PERSON

 

IA; OO; HC

 

 

1The percentages reported in this Schedule 13G are based upon 38,221,187 shares of common stock outstanding as of July 23, 2020 after the exercise of the underwriters’ option (according to the issuer’s prospectus as filed with the Securities and Exchange Commission on July 24, 2020). Except as described in the preceding sentence, all share numbers for the holdings of the reporting persons reported in this Schedule 13G are as of the opening of the market on August 7, 2020.

 

 

 

 

 1.

NAME OF REPORTING PERSON

 

Citadel Advisors Holdings LP

 2.

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

 

(a) ¨

(b) ¨

 3.

SEC USE ONLY

 

 4.

 

CITIZENSHIP OR PLACE OF ORGANIZATION

 

Delaware

NUMBER OF

SHARES

BENEFICIALLY

OWNED BY

EACH

REPORTING

PERSON

WITH 

5.

SOLE VOTING POWER

 

0 

6.

SHARED VOTING POWER

 

2,120,333 shares 

7.

SOLE DISPOSITIVE POWER

 

0 

8.

SHARED DISPOSITIVE POWER

 

See Row 6 above

9.

AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 

See Row 6 above

10.

CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES ¨

 

11.

PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

 

5.5%

12.

TYPE OF REPORTING PERSON

 

PN; HC

 

 

 

 

1.

NAME OF REPORTING PERSON

 

Citadel GP LLC

2.

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

 

(a) ¨

(b) ¨

3.

SEC USE ONLY

 

4.

 

CITIZENSHIP OR PLACE OF ORGANIZATION

 

Delaware

NUMBER OF

SHARES

BENEFICIALLY

OWNED BY

EACH

REPORTING

PERSON

WITH 

5.

SOLE VOTING POWER

 

0 

6.

SHARED VOTING POWER

 

2,120,333 shares 

7.

SOLE DISPOSITIVE POWER

 

0 

8.

SHARED DISPOSITIVE POWER

 

See Row 6 above

9.

AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 

See Row 6 above.

10.

CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES ¨

 

11.

PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

 

5.5%

12.

 

TYPE OF REPORTING PERSON

 

OO; HC

 

 

 

 

1.

NAME OF REPORTING PERSON 

 

Citadel Securities LLC

2.

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

 

(a) ¨

(b) ¨

3.

SEC USE ONLY

 

4.

CITIZENSHIP OR PLACE OF ORGANIZATION

 

Delaware

NUMBER OF

SHARES

BENEFICIALLY

OWNED BY

EACH

REPORTING

PERSON

WITH 

5.

SOLE VOTING POWER

 

0 

6.

SHARED VOTING POWER

 

0 shares 

7.

SOLE DISPOSITIVE POWER

 

0 

8.

SHARED DISPOSITIVE POWER

 

See Row 6 above

9.

AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 

See Row 6 above.

10.

CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES ¨

 

11.

PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

 

0%

12.

TYPE OF REPORTING PERSON

 

BD, OO

 

 

 

 

1.

NAME OF REPORTING PERSON

 

CALC IV LP

2.

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

 

(a) ¨

(b) ¨

3.

SEC USE ONLY

 

4.

CITIZENSHIP OR PLACE OF ORGANIZATION

 

Delaware

NUMBER OF

SHARES

BENEFICIALLY

OWNED BY

EACH

REPORTING

PERSON

WITH 

5.

SOLE VOTING POWER

 

0 

6.

SHARED VOTING POWER

 

0 shares 

7.

SOLE DISPOSITIVE POWER

 

0 

8.

SHARED DISPOSITIVE POWER

 

See Row 6 above

 9.

AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 

See Row 6 above.

 10.

CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES ¨

 

 11.

PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

 

0%

 12.

 

TYPE OF REPORTING PERSON

 

PN; HC

 

 

 

 

1.

NAME OF REPORTING PERSON 

 

Citadel Securities GP LLC

2.

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

 

(a) ¨

(b) ¨

3.

SEC USE ONLY

 

4.

CITIZENSHIP OR PLACE OF ORGANIZATION

 

Delaware

NUMBER OF

SHARES

BENEFICIALLY

OWNED BY

EACH

REPORTING

PERSON

WITH 

5.

SOLE VOTING POWER

 

0 

6.

SHARED VOTING POWER

 

0 shares 

7.

SOLE DISPOSITIVE POWER

 

0 

8.

SHARED DISPOSITIVE POWER

 

See Row 6 above

9.

AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 

See Row 6 above.

10.

CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES ¨

 

11.

PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

 

0%

12.

 

TYPE OF REPORTING PERSON

 

OO; HC

 

 

 

 

1.

NAME OF REPORTING PERSON 

 

Kenneth Griffin

2.

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

 

(a) ¨

(b) ¨

3.

SEC USE ONLY

 

4.

 

CITIZENSHIP OR PLACE OF ORGANIZATION

 

U.S. Citizen

NUMBER OF

SHARES

BENEFICIALLY

OWNED BY

EACH

REPORTING

PERSON

WITH 

5.

SOLE VOTING POWER

 

0 

6.

SHARED VOTING POWER

 

2,120,333 shares 

7.

SOLE DISPOSITIVE POWER

 

0 

8.

SHARED DISPOSITIVE POWER

 

See Row 6 above

9.

AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 

See Row 6 above

10.

CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES ¨

 

11.

PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

 

5.5%

12.

 

TYPE OF REPORTING PERSON

 

IN; HC

 

 

 

  

Item 1(a) Name of Issuer
  Annexon, Inc.
   
Item 1(b) Address of Issuer’s Principal Executive Offices
  180 Kimball Way, Suite 200, South San Francisco, California 94080
   
Item 2(a) Name of Person Filing
  This Schedule 13G is being jointly filed by Citadel Advisors LLC (“Citadel Advisors”), Citadel Advisors Holdings LP (“CAH”), Citadel GP LLC (“CGP”), Citadel Securities LLC (“Citadel Securities”), CALC IV LP (“CALC4”), Citadel Securities GP LLC (“CSGP”) and Mr. Kenneth Griffin (collectively with Citadel Advisors, CAH, CGP, Citadel Securities, CALC4 and CSGP, the “Reporting Persons”) with respect to shares of common stock of the above-named issuer owned by Citadel Multi-Strategy Equities Master Fund Ltd., a Cayman Islands limited company (“CM”).
   
  Citadel Advisors is the portfolio manager for CM.  CAH is the sole member of Citadel Advisors.  CGP is the general partner of CAH.  CALC4 is the non-member manager of Citadel Securities.  CSGP is the general partner of CALC4.  Mr. Griffin is the President and Chief Executive Officer of CGP, and owns a controlling interest in CGP and CSGP.
   
  The filing of this statement shall not be construed as an admission that any of the Reporting Persons is the beneficial owner of any securities covered by the statement other than the securities actually owned by such person (if any).
   
Item 2(b) Address of Principal Business Office
  The address of the principal business office of each of the Reporting Persons is 131 S. Dearborn Street, 32nd Floor, Chicago, Illinois 60603.
   
Item 2(c) Citizenship
  Each of Citadel Advisors, CGP, Citadel Securities and CSGP is organized as a limited liability company under the laws of the State of Delaware.  Each of CALC4 and CAH is organized as a limited partnership under the laws of the State of Delaware.  Mr. Griffin is a U.S. citizen.
   
Item 2(d) Title of Class of Securities
  Common stock
   
Item 2(e) CUSIP Number
  03589W102

 

 

 

 

Item 3If this statement is filed pursuant to Rules 13d-1(b), or 13d-2(b) or (c), check whether the person filing is a:

  

  (a) ¨ Broker or dealer registered under Section 15 of the Exchange Act;
       
  (b) ¨ Bank as defined in Section 3(a)(6) of the Exchange Act;
       
  (c) ¨ Insurance company as defined in Section 3(a)(19) of the Exchange Act;
       
  (d) ¨ Investment company registered under Section 8 of the Investment Company Act;
       
  (e) ¨ An investment adviser in accordance with Rule 13d-1(b)(1)(ii)(E);
       
  (f) ¨ An employee benefit plan or endowment fund in accordance with Rule 13d-1(b)(1)(ii)(F);
       
  (g) ¨ A parent holding company or control person in accordance with Rule 13d-1(b)(1)(ii)(G);
       
  (h) ¨ A savings association as defined in Section 3(b) of the Federal Deposit Insurance Act;
       
  (i) ¨ A church plan that is excluded from the definition of an investment company under Section 3(c)(14) of the Investment Company Act;
       
  (j) ¨ A non-U.S. institution in accordance with Rule 13d-1(b)(1)(ii)(J);
       
  (k) ¨ Group, in accordance with Rule 13d-1(b)(1)(ii)(K).

 

If filing as a non-U.S. institution in accordance with Rule 13d-1(b)(1)(ii)(J), please specify the type of institution: ____________.

 

 

 

 

Item 4Ownership

 

A.Citadel Advisors LLC, Citadel Advisors Holdings LP and Citadel GP LLC

 

(a)Each of Citadel Advisors LLC, Citadel Advisors Holdings LP and Citadel GP LLC may be deemed to beneficially own 2,120,333 shares of common stock.

 

(b)The number of shares that each of Citadel Advisors LLC, Citadel Advisors Holdings LP and Citadel GP LLC may be deemed to beneficially own constitutes approximately 5.5% of the common stock outstanding.

 

(c)Number of shares as to which such person has:

 

(i)sole power to vote or to direct the vote: 0

 

(ii)shared power to vote or to direct the vote: 2,120,333

 

(iii)sole power to dispose or to direct the disposition of: 0

 

(iv)shared power to dispose or to direct the disposition of: 2,120,333

 

B.Citadel Securities LLC, CALC IV LP and Citadel Securities GP LLC

 

(a)Each of Citadel Securities, CALC IV LP and Citadel Securities GP LLC may be deemed to beneficially own 0 shares of common stock.

 

(b)The number of shares that each of Citadel Securities, CALC IV LP and Citadel Securities GP LLC may be deemed to beneficially own constitutes 0% of the common stock outstanding.

 

(c)Number of shares as to which such person has:

 

(i)sole power to vote or to direct the vote: 0

 

(ii)shared power to vote or to direct the vote: 0

 

(iii)sole power to dispose or to direct the disposition of: 0

 

(iv)shared power to dispose or to direct the disposition of: 0

 

C.Kenneth Griffin

 

(a)Mr. Griffin may be deemed to beneficially own 2,120,333 shares of common stock.

 

(b)The number of shares that Mr. Griffin may be deemed to beneficially own constitutes approximately 5.5% of the common stock outstanding.

 

(c)Number of shares as to which such person has:

 

(i)sole power to vote or to direct the vote: 0

 

(ii)shared power to vote or to direct the vote: 2,120,333

 

(iii)sole power to dispose or to direct the disposition of: 0

 

(iv)shared power to dispose or to direct the disposition of: 2,120,333

 

 

 

 

Item 5 Ownership of Five Percent or Less of a Class
  If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than 5 percent of the class of securities, check the following ¨.
   
Item 6 Ownership of More than Five Percent on Behalf of Another Person
  Not Applicable
   
Item 7 Identification and Classification of the Subsidiary which Acquired the Security Being Reported on by the Parent Holding Company
  See Item 2 above
   
Item 8 Identification and Classification of Members of the Group
  Not Applicable
   
Item 9 Notice of Dissolution of Group
  Not Applicable
   
Item 10 Certification
  By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect.

  

 

 

 

After reasonable inquiry and to the best of its knowledge and belief, the undersigned certify that the information set forth in this statement is true, complete and correct.

 

Dated this 7th day of August, 2020.

 

CITADEL SECURITIES LLC   CITADEL ADVISORS LLC
         
By: /s/ Guy Miller   By: /s/ Noah Goldberg
  Guy Miller, Authorized Signatory     Noah Goldberg, Authorized Signatory
         
CALC IV LP   CITADEL ADVISORS HOLDINGS LP
         
By: /s/ Guy Miller   By: /s/ Noah Goldberg
  Guy Miller, Authorized Signatory     Noah Goldberg, Authorized Signatory
         
CITADEL SECURITIES GP LLC   CITADEL GP LLC
         
By: /s/ Guy Miller   By: /s/ Noah Goldberg
  Guy Miller, Authorized Signatory     Noah Goldberg, Authorized Signatory
         
      KENNETH GRIFFIN
         
      By: /s/ Noah Goldberg
        Noah Goldberg, attorney-in-fact*