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

SCHEDULE 13G

Under the Securities Exchange Act of 1934

(Amendment No. 4)*


Micron Technology

(Name of Issuer)

Common

(Title of Class of Securities)

 

 

595112103

 

 
   
(CUSIP Number)
   

 

(Date of Event Which Requires Filing of this Statement)

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

        *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).

Page 1 of 4 Pages


Schedule 13G

CUSIP No. 595112103


(1)   NAMES OF REPORTING PERSONS.
I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY).

 

 

PRIMECAP Management Company                                      95-3868081

(2)   Check the Appropriate Box if a Member of a Group (See Instructions)
    (a) o
    (b) o

(3)   SEC USE ONLY

 

 

 

(4)   CITIZENSHIP OR PLACE OF ORGANIZATION    

 

 

225 South Lake Avenue #400, Pasadena, CA 91101-3005

    (5)   SOLE VOTING POWER
        5,355,506
Number of  
Shares   (6)   SHARED VOTING POWER  
Beneficially       -0-
Owned by  
Each   (7)   SOLE DISPOSITIVE POWER  
Reporting       43,248,756
Person With:  
    (8)   SHARED DISPOSITIVE POWER
        -0-

(9)   AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 

 

43,248,756

(10)   CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)

 

 

o

(11)   PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)    

 

 

7.12%

(12)   TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)

 

 

IA

SEE INSTRUCTION BEFORE FILLING OUT!

Page 2 of 4 Pages


Item 10. Certification


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.

     
    March 31, 2003
   
Date
     
    /s/ THEO A. KOLOKOTRONES
   
Signature
     
    Theo A. Kolokotrones, President
   
Name/Title

Page 3 of 4 Pages




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SIGNATURE