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

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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(Print or Type Responses)
1. Name and Address of Reporting Person *
Smith Family Trusts
  2. Issuer Name and Ticker or Trading Symbol
SMITH A O CORP [AOS]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
C/O SMITH INVESTMENT COMPANY, 11270 WEST PARK PLACE
3. Date of Earliest Transaction (Month/Day/Year)
04/14/2009
(Street)

MILWAUKEE, WI 53224
4. If Amendment, Date Original Filed(Month/Day/Year)
6. Individual or Joint/Group Filing(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 Following Reported Transaction(s)
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock               4,734 D (1)  
Common Stock               2,649 I See Note (2)
Common Stock               105,811 I See Note (3)

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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 Following Reported Transaction(s)
(Instr. 4)
10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)
11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Class A Common Stock $ 0 (4)               (5)   (6) Common Stock 547,506   547,506 I See Note (7)
Phantom Stock (10) $ 27.675 04/14/2009   A   3,253 (8)     (9)   (9) Common Stock 3,253 $ 0 10,413 D (10)  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
Smith Family Trusts
C/O SMITH INVESTMENT COMPANY
11270 WEST PARK PLACE
MILWAUKEE, WI 53224
    X    

Signatures

 Bruce M. Smith as Representative for Smith Family Trusts   04/15/2009
**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 direct ownership of the Issuer's Common Stock by certain individuals or trusts that form part of the Reporting Person.
(2) Represents the indirect ownership of the Issuer's Common Stock by one individual who is part of the Reporting Person under the A. O. Smith Corporation Directors' Deferred Compensation Plan (the "Plan").
(3) Represents the Reporting Person's proportionate interest in shares of the Issuer's Common Stock held by SICO, including certain shares held in trust. Beneficial ownership of the shares of the Issuer owned by SICO is disclaimed.
(4) Convertible on a 1 for 1 basis.
(5) Convertible at any time.
(6) None.
(7) Represents the Reporting Person's proportionate interest in shares of the Issuer's Class A Common Stock held by SICO, including certain shares held in trust. Beneficial ownership of the shares of the Issuer owned by SICO is disclaimed.
(8) Payment of portion of retainer in phantom stock to one individual, who is a director of the Issuer and part of the Reporting Person, under the Plan.
(9) The Plan allows for the payment of a retainer in phantom stock and it also permits the participant/recipient to defer receipt of the award. One individual who is part of the Reporting Person made a deferral pursuant to the Plan.
(10) Represents direct ownership of the Issuer's phantom stock by one individual who is part of the Reporting Person.
 
Remarks:
Explanation of Responses:

The Smith Family Trusts (the "Reporting Person") consist of certain shareholders of Smith Investment Company, a Nevada corporation ("SICO"), that holds shares of A. O. Smith Corporation (the "Issuer").  The shareholders of SICO that comprise the Reporting Person are certain individual members of the Smith family and trusts for the benefit of certain members of the Smith family.  On December 10, 2008, the Reporting Person filed a Schedule 13D/A related to the Issuer's Common Stock pursuant to Section 13(d) of the Securities Exchange Act of 1934 (the "Exchange Act").  The collective beneficial ownership of the Issuer's outstanding Common Stock under Rule 13d-3 under the Exchange Act exceeds 10% of the Issuer's Common Stock.  The Reporting Person disclaims beneficial ownership of the shares of the Issuer's Common Stock held by SICO and also disclaims that the Reporting Person constitutes a "group" pursuant to Section 13(d).

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