SEC Form 5

FORM 5		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 ANNUAL STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940	OMB APPROVAL OMB Number: 3235-0362 Estimated average burden hours per response: 1.0
	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.

1. Name and Address of Reporting Person* SMITH MARK D (Last) (First) (Middle) 3725 WEST GRACE AVENUE (Street) MEQUON WI 53092 (City) (State) (Zip)	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)
	3. Statement for Issuer's Fiscal Year Ended (Month/Day/Year) 12/31/2010
	4. If Amendment, Date of 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

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							19,453(1)	D
Common Stock	01/29/2010		G	582	A	$0	5,556	I	In trust(2)
Common Stock	07/07/2010		G	578	A	$0	9,201(3)	I	In trust(2)
Common Stock	12/17/2010		G	659	D	$0	8,542	I	In trust(2)
Common Stock	06/28/2010		G	579	A	$0	1,920(4)	I	Held by spouse

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 Securities Underlying Derivative Security (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: 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(5)						(6)	(7)	Common Stock	0		43,149(8)	I	In trust(2)
Class A Common Stock	$0(5)						(6)	(7)	Common Stock	0		919(9)	I	Held by spouse

Explanation of Responses:

1. On November 15, 2010, the common stock of A. O. Smith Corporation split 3-for-2, resulting in the reporting person's ownership of 6,484 additional shares of common stock.

2. The reporting person beneficially owns the shares as settlor of a revocable family trust.

3. On November 15, 2010, the common stock of A. O. Smith Corporation split 3-for-2, resulting in the reporting person's beneficial ownership of 3,067 additional shares of common stock.

4. On November 15, 2010, the common stock of A. O. Smith Corporation split 3-for-2, resulting in the reporting person's beneficial ownership of 640 additional shares of common stock.

5. 1 for 1

6. Convertible at any time.

7. None.

8. On November 15, 2010, the common stock of A. O. Smith Corporation split 3-for-2, resulting in the reporting person's beneficial ownership of 14,383 additional shares of Class A Common Stock.

9. On November 15, 2010, the common stock of A. O. Smith Corporation split 3-for-2, resulting in the reporting person's beneficial ownership of 306 additional shares of Class A Common Stock.

Remarks:

	Kenneth J. Maciolek, Attorney-in-Fact for Mark D. Smith	02/04/2011
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* 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).
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