<SEC-DOCUMENT>0001047469-13-001056.txt : 20130214
<SEC-HEADER>0001047469-13-001056.hdr.sgml : 20130214
<ACCEPTANCE-DATETIME>20130214100338
ACCESSION NUMBER:		0001047469-13-001056
CONFORMED SUBMISSION TYPE:	13F-HR/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20120930
FILED AS OF DATE:		20130214
DATE AS OF CHANGE:		20130214
EFFECTIVENESS DATE:		20130214

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Magnetar Financial LLC
		CENTRAL INDEX KEY:			0001352851
		IRS NUMBER:				043818748
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		13F-HR/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	028-11800
		FILM NUMBER:		13607151

	BUSINESS ADDRESS:	
		STREET 1:		1603 ORRINGTON AVE.
		STREET 2:		13TH FLOOR
		CITY:			EVANSTON
		STATE:			IL
		ZIP:			60201
		BUSINESS PHONE:		(847)905-4400

	MAIL ADDRESS:	
		STREET 1:		1603 ORRINGTON AVE.
		STREET 2:		13TH FLOOR
		CITY:			EVANSTON
		STATE:			IL
		ZIP:			60201
</SEC-HEADER>
<DOCUMENT>
<TYPE>13F-HR/A
<SEQUENCE>1
<FILENAME>a2212729z13f-hra.txt
<DESCRIPTION>13F-HR/A
<TEXT>
<Page>

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                    FORM 13F

                               FORM 13F COVER PAGE

Report for the Calendar Year or Quarter Ended: September 30, 2012
                                               -----------------------

Check Here if Amendment /X/; Amendment Number: 1
                                               ---------
   This Amendment (Check only one.):    / / is a restatement.
                                        /X/ adds new holdings entries.

Institutional Investment Manager Filing this Report:

   Name:         Magnetar Financial LLC
                 ---------------------------------
   Address:      1603 Orrington Avenue, 13th Floor
                 ---------------------------------
                 Evanston, IL  60201
                 ---------------------------------

Form 13F File Number: 28-11800
                         ---------------------

The institutional investment manager filing this report and the person by whom
it is signed hereby represent that the person signing the report is authorized
to submit it, that all information contained herein is true, correct and
complete, and that it is understood that all required items, statements,
schedules, lists, and tables, are considered integral parts of this form.

Person Signing this Report on Behalf of Reporting Manager:

Name:    Michael Turro
         -------------------------------
Title:   Chief Compliance Officer
         -------------------------------
Phone:   847-905-4690
         -------------------------------

Signature, Place, and Date of Signing:

          /s/Michael Turro               Evanston, IL     February 14, 2013
   -------------------------------    -----------------   -----------------
           [Signature]                  [City, State]           [Date]

Report Type (Check only one.):

/x/ 13F HOLDINGS REPORT. (Check here if all holdings of this reporting
    manager are reported in this report.)

/ / 13F NOTICE. (Check here if no holdings reported are in this report,
    and all holdings are reported by other reporting manager(s).)

/ / 13F COMBINATION REPORT. (Check here if a portion of the holdings for this
    reporting manager are reported in this report and a portion are reported by
    other reporting manager(s).)

<Page>

                              FORM 13F SUMMARY PAGE

Report Summary:

Number of Other Included Managers:      0
                                        --------------------

Form 13F Information Table Entry Total: 6
                                        --------------------

Form 13F Information Table Value Total: $ 302,510
                                        --------------------
                                            (thousands)

THIS FILING LISTS  SECURITIES  HOLDINGS  REPORTED ON THE FORM 13F FILED ON
NOVEMBER 14, 2012 PURSUANT TO A REQUEST FOR  CONFIDENTIAL TREATMENT AND FOR
WHICH THE CONFIDENTIAL TREATMENT EXPIRED ON FEBRUARY 14, 2013 OR ARE NO LONGER
NECESSARY.

List of Other Included Managers: NONE

<Page>

                           FORM 13F INFORMATION TABLE

<Table>
<Caption>
       COLUMN 1           COLUMN 2 COLUMN 3   COLUMN 4        COLUMN 5       COLUMN 6  COLUMN 7       COLUMN 8
---------------------------------------------------------------------------------------------------------------------
  NAME OF                 TITLE OF              VALUE    SHRS OR  SH/  PUT/ INVESTMENT OTHER      VOTING AUTHORITY
  ISSUER                  CLASS      CUSIP    [x$1000]   PRN AMT  PRN  CALL DISCRETION MANAGERS    SOLE   SHARED NONE
---------------------------------------------------------------------------------------------------------------------
<S>                         <C>    <C>         <C>      <C>       <C>  <C>  <C>        <C>      <C>       <C>    <C>
*  MEDICIS PHARMACEUTICAL
    CORP  CL A              NEW    584690309    16,239    375,300 SH                              375,300
*  SHAW GROUP INC           COM    820280105    47,708  1,093,729 SH                            1,093,729
*  SHAW GROUP INC           COM    820280105     4,362    100,000 SH   CALL                       100,000
*  TEMPUR PEDIC INTL INC    COM    88023U101     8,220    275,000 SH                              275,000
*  COOPER INDUSTRIES PLC    SHS    G24140108   211,849  2,822,397 SH                            2,822,397
*  GEOEYE INC               COM    37250W108    14,132    534,700 SH                              534,700
</Table>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>