Ownership Submission
FORM 5
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
Form 3 Holdings Reported
Form 4 Transactions Reported
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

ANNUAL STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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1. Name and Address of Reporting Person *
SMITH MARK D
 2. Issuer Name and Ticker or Trading Symbol
SMITH A O CORP [AOS] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director _____ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)

3725 WEST GRACE AVENUE		 3. Statement for Issuer's Fiscal Year Ended (Month/Day/Year)
12/31/2009
(Street)


MEQUON, WI 53092		 4. If Amendment, Date Original Filed(Month/Day/Year)
02/05/2010		 6. Individual or Joint/Group Reporting
(check applicable line)

_X_ Form Filed by One Reporting Person
___ Form Filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)		 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)		 4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)		 5. Amount of Securities Beneficially Owned at end of Issuer's Fiscal Year
(Instr. 3 and 4)		 6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)		 7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Amount (A) or (D) Price
Common Stock 05/28/2009   A4 40 A $ (1) 118 I Held by spouse

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number. SEC 2270 (9-02)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)		 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)		 5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)		 6. Date Exercisable and Expiration Date
(Month/Day/Year)		 7. Title and Amount of Underlying Securities
(Instr. 3 and 4)		 8. Price of Derivative Security
(Instr. 5)		 9. Number of Derivative Securities Beneficially Owned at End of Issuer's Fiscal Year
(Instr. 4)		 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)		 11. Nature of Indirect Beneficial Ownership
(Instr. 4)
(A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Class A Common Stock $ 0 (2) 05/28/2009   A4 (1) 613     (3)   (4) Common Stock
 
$ 0 613
I
Held by spouse

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
SMITH MARK D
3725 WEST GRACE AVENUE
MEQUON, WI 53092		   X      

Signatures

James F. Stern, Attorney-in-Fact for Mark D. Smith 02/04/2011
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) Represents the conversion of shares of Smith Investment Company ("SICO") common stock held by his spouse into shares of Common Stock and Class A Common Stock of A. O. Smith Corporation ("the "Issuer") pursuant to a merger of SICO with a subsidiary of the Issuer (the "Merger"). No consideration was paid or received except for the conversion of each SICO share into shares of the Issuer's Common Stock and Class A Common Stock. The conversion in the Merger was approved in advance by the Issuer's board of directors on behalf of the reporting person. Also, certain shares of the Issuer's Common Stock issued in the Merger are being held in escrow pursuant to the related merger agreement.
(2) 1 for 1
(3) Convertible at any time
(4) None

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