Schedule 13G Amendment No. 3

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

 

 

SCHEDULE 13G

 

 

UNDER THE SECURITIES EXCHANGE ACT OF 1934

(AMENDMENT NO. 3)*

 

 

 

Union Pacific Corporation


(Name of Issuer)

 

Common


(Title of Class of Securities)

 

 

907818108


                                (CUSIP Number)                                 

 

December 31, 2005


(Date of Event Which Requires Filing of this Statement)

 

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

 

x Rule 13d-1(b)

 

¨ 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 the disclosures provided in a prior cover page.

 

The information required in 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).

 

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    CUSIP NO. 907818108

   13G    PAGE 2 OF 5 PAGES    

 

  1  

NAME OF REPORTING PERSON

S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

 

            Dodge & Cox

            94-1441976

   
  2  

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*

(a)  ¨

(b)  ¨

 

            N/A

   
  3  

SEC USE ONLY

 

   
  4  

CITIZENSHIP OR PLACE OF ORGANIZATION

 

            California - U.S.A.

   

NUMBER OF

SHARES

BENEFICIALLY

OWNED BY

EACH

REPORTING

PERSON

WITH

 

  5    SOLE VOTING POWER

 

                26,420,993


  6    SHARED VOTING POWER

 

                287,900


  7    SOLE DISPOSITIVE POWER

 

                28,171,494


  8    SHARED DISPOSITIVE POWER

 

                0

  9  

AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 

            28,171,494

   
10  

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

 

            N/A

   
11  

PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

 

            10.6%

   
12  

TYPE OF REPORTING PERSON*

 

            IA

   

 

 

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Item 1  

(a)

   Name of Issuer:          
         Union Pacific Corporation          
Item 1  

(b)

   Address of Issuer’s Principal Executive Offices:          
        

1400 Douglas Street

Omaha, NE 68179-1920

         
Item 2  

(a)

   Name of Person Filing:          
         Dodge & Cox          
Item 2  

(b)

   Address of the Principal Office or, if none, Residence:          
        

555 California Street, 40th Floor

San Francisco, CA 94104

         
Item 2  

(c)

   Citizenship:          
         California - U.S.A.          
Item 2  

(d)

   Title of Class of Securities:          
         Common          
Item 2  

(e)

   CUSIP Number:          
         907818108          
Item 3   If the Statement is being filed pursuant to Rule 13d-1(b), or 13d-2(b), check whether the person filing is a:     
    (e)    x    Investment Advisor registered under section 203 of the Investment Advisors Act of 1940

 

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Item 4   Ownership:     
    (a)    Amount Beneficially Owned:          
         28,171,494          
    (b)    Percent of Class:          
         10.6%          
    (c)    Number of shares as to which such person has:          
         (i)    sole power to vote or direct the vote:          
              26,420,993          
         (ii)    shared power to vote or direct the vote:          
              287,900          
         (iii)    sole power to dispose or to direct the disposition of:          
              28,171,494          
         (iv)    shared power to dispose or to direct the disposition of:          
              0          

Item 5

  Ownership of Five Percent or Less of a Class:     
    Not applicable.     

Item 6

  Ownership of More than Five Percent on Behalf of Another Person:          
    Securities reported on this Schedule 13G are beneficially owned by clients of Dodge & Cox, which clients may include investment companies registered under the Investment Company Act and/or employee benefit plans, pension funds, endowment funds or other institutional clients.          

Item 7

  Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on By the Parent Holding Company:
    Not applicable.

Item 8

  Identification and Classification of Members of the Group:          
    Not applicable.          

Item 9

  Notice of Dissolution of a 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 acquired in the ordinary course of business and were not acquired for the purpose of and do not have the effect of changing or influencing the control of the issuer of such securities and were not acquired in connection with or as a participant in any transaction having such purpose or effect.          

 

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SIGNATURE

 

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

 

Dated: February 3, 2006

 

DODGE & COX

By:

 

/S/ THOMAS M. MISTELE


Name:

 

Thomas M. Mistele

Title:

 

Chief Counsel & COO

 

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