UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549





Form 10-K/A

(Amendment No.1)



|x | ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
|- | ------------------------------------------------------------------------------------

FOR THE FISCAL YEAR ENDED DECEMBER 31, 2011

OR



| ̈ | TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
|- | ----------------------------------------------------------------------------------------

001-32878

(Commission File Number)





PENSON
WORLDWIDE, INC.

(Exact name of registrant as specified in its charter)



|                                                               |  |                                                          |  |                                     
|-------------------------------------------------------------- |  | -------------------------------------------------------- |  | ------------------------------------
|Delaware                                                       |  | 6211                                                     |  | 75-2896356                          
|(State or Other Jurisdiction of
Incorporation or Organization) |  | (Primary Standard Industrial Classification Code Number) |  | (I.R.S. Employer Identification No.)

1700 Pacific Avenue, Suite 1400

Dallas, Texas 75201

(214) 765-1100

(Address, including zip code, and telephone number,
including area code, of the registrants principal executive offices)

Securities registered pursuant to
Section 12(b) of the Act



|                                        |  |                                          
|--------------------------------------- |  | -----------------------------------------
|Title of Each Class                     |  | Name of Each Exchange on Which Registered
|Common Stock, par value $0.01 per share |  | NASDAQ Global Select Market              

Securities registered pursuant to Section 12(g) of the Act

None





Indicate by
check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.    Yes   ̈    No  x

Indicate by check mark if the registrant is not required to file reports pursuant
to Section 13 or Section 15(d) of the Act.    Yes   ̈    No  x

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every
Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such
files).    Yes  x    No   ̈

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the
Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports) and (2) has been subject to such filing requirements for the past
90 days.    Yes  x    No   ̈

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and
will not be contained, to the best of registrants knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K.   ̈

Indicate by check mark whether the registrant is a large accelerated filer, an
accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of large accelerated filer, accelerated filer and smaller reporting company in Rule 12b-2 of the Exchange Act.
(Check one):



|                        |  |                                                  |  |                           |  |  
|----------------------- |  | ------------------------------------------------ |  | ------------------------- |  | -
|Large accelerated filer |  |  ̈                                                |  | Accelerated filer         |  | x
|                        |  |                                                  | 
|Non-accelerated filer   |  |  ̈  (Do not check if a smaller reporting company) |  | Smaller reporting company |  |  ̈

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the
Exchange Act).    Yes   ̈    No  x

The aggregate market value of the registrants common stock held by non-affiliates as of June 30, 2011 (the last business day
of the registrants most recently completed second fiscal quarter) was $57,305,604.

The number of outstanding shares of
the registrants Common Stock, $0.01 par value, as of March 12, 2012 was 27,984,321.









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EXPLANATORY NOTE

This Amendment No. 1 on Form 10-K/A (this Amendment) amends Penson Worldwide, Inc.s (unless otherwise indicated,
all references in this Amendment to we and our refer to Penson Worldwide, Inc. and our subsidiaries) Annual Report on Form 10-K for the fiscal year ended December 31, 2011, originally filed on March 15, 2012 (the
Original Filing). We are filing this Amendment to replace Exhibit 10.45 to include certain portions of the Exhibit that had previously been omitted or redacted pursuant to a request for confidential treatment. This Amendment
provides a revised redacted version of Exhibit 10.45.

Except as described above, no other changes have been made to the
Original Filing. The Original Filing continues to speak as of the date of the Original Filing, and we have not updated the disclosures contained therein to reflect any events which occurred at a date subsequent to the filing of the Original Filing.

PART IV

ITEM 15. EXHIBITS AND FINANCIAL STATEMENT SCHEDULES

(b) See Exhibit Index attached hereto.



2



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Signatures

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused the report to be signed on its behalf by the undersigned, thereunto duly
authorized.



PENSON WORLDWIDE, INC.By:

/s/ Philip A. PendergraftName:

Philip A. PendergraftTitle:

Chief Executive Officer


Date: June 29, 2012

Pursuant to the requirements of the Securities Exchange Act of 1934, this report has been signed by the following persons in the capacities and on the dates indicated:



|                                |  |                                                    |  |              
|------------------------------- |  | -------------------------------------------------- |  | -------------
|Signature                       |  | Title                                              |  | Date         
|                                |  |                                                   
|/s/ Roger J. Engemoen, Jr.      |  | Chairman                                           |  | June 29, 2012
|Roger J. Engemoen, Jr.          |  |                                                    |  |              
|                                |  |                                                   
|/s/ Philip A. Pendergraft       |  | Chief Executive Officer                            |  | June 29, 2012
|Philip A. Pendergraft           |  | (Principal Executive Officer) and Director         |  |              
|                                |  |                                                   
|/s/ Daniel P. Son Daniel P. Son |  | Non Executive Vice Chairman and Director           |  | June 29, 2012
|                                |  |                                                   
|/s/ Bart McCain Bart McCain     |  | Executive Vice President & Chief Financial Officer |  | June 29, 2012
|                                |  | (Principal Financial and Accounting Officer)       |  |              
|                                |  |                                                   
|/s/ Robert S. Basso             |  | Director                                           |  | June 29, 2012
|Robert S. Basso                 |  |                                                    |  |              
|                                |  |                                                   
|/s/ David Johnson               |  | Director                                           |  | June 29, 2012
|David Johnson                   |  |                                                    |  |              
|                                |  |                                                   
|/s/ David M. Kelly              |  | Director                                           |  | June 29, 2012
|David M. Kelly                  |  |                                                    |  |              
|                                |  |                                                   
|/s/ Diane L. Schueneman         |  | Director                                           |  | June 29, 2012
|Diane L. Schueneman             |  |                                                    |  |              



3



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INDEX TO EXHIBITS



|        |  |                                                                                                                                                                                                                                                                                   
|------- |  | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|Exhibit |  | Description                                                                                                                                                                                                                                                                       
|        | 
|10.45  |  | Third Amendment to the Second Amended and Restated Credit Agreement, dated the 6th day of December, 2011, by and among the Company, Regions Bank, as Administrative Agent, Swing Line
Lender, and Letter of Credit Issuer, the lenders party thereto and the other parties thereto
|        | 
|31.1    |  | Certification of Chief Executive Officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002 (filed herewith)                                                                                                                                                               
|        | 
|31.2    |  | Certification of Chief Financial Officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002 (filed herewith)                                                                                                                                                               



| | Confidential treatment has been requested for certain information contained in this document. Such information has been omitted and filed separately with the
Securities and Exchange Commission.
|- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------