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

                                   Form 13F

                              Form 13F COVER PAGE

Report for the Calendar Year or Quarter Ended: June 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, 13(th) 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          November 14, 2012
_______________________    ________________________    _______________________
      [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).)

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                                   FORM 13F

                                 SUMMARY PAGE


Report Summary:

Number of Other Included Managers:      0

Form 13F Information Table Entry Total: 4

Form 13F Information Table Value Total: $266,590
                                       (thousands)

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

List of Other Included Managers: NONE



                          FORM 13F INFORMATION TABLE



COLUMN 1                      COLUMN 2 COLUMN 3  COLUMN 4      COLUMN 5       COLUMN 6  COLUMN 7       COLUMN 8
--------                      -------- --------- -------- ------------------ ---------- -------- ---------------------
                                                                                                   VOTING AUTHORITY
                              TITLE OF            VALUE    SHRS OR  SH/ PUT/ INVESTMENT  OTHER   ---------------------
NAME OF ISSUER                 CLASS    CUSIP    [x$1000]  PRN AMT  PRN CALL DISCRETION MANAGERS   SOLE    SHARED NONE
--------------                -------- --------- -------- --------- --- ---- ---------- -------- --------- ------ ----
                                                                                 
ARIBA INC                     COM NEW  04033V203 107,424  2,400,000 SH          SOLE             2,400,000
DOLLAR THRIFTY AUTOMOTIVE GP      COM  256743105  35,031    432,700 SH          SOLE               432,700
DOLLAR THRIFTY AUTOMOTIVE GP      COM  256743105  33,194    410,000 SH  PUT     SOLE               410,000
SUNOCO INC                        COM  86764P109  90,941  1,914,555 SH          SOLE             1,914,555