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 * BLACKBURN MARK A   2. Issuer Name and Ticker or Trading Symbol State Auto Financial CORP [STFC] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director __X__ 10% Owner __X__ Officer (give title below) _____ Other (specify below) Senior Vice President (Last) (First) (Middle) 518 E. BROAD STREET 3. Date of Earliest Transaction (Month/Day/Year) 05/17/2006 (Street) COLUMBUS, OH 43215 4. If Amendment, Date Original Filed(Month/Day/Year) 05/19/2006 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 Shares without par value 05/17/2006   A   10,000 A $ 0 17,024.866 (3) (4) (5) D

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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

Employee Stock Option (Right to Buy) NQ

$ 33.5

05/17/2006

A

15,939

05/17/2007(2)

05/16/2016

Common Shares

15,939

$ 0 (1)

15,939

D

Employee Stock Option (Right to Buy)ISO

$ 33.5

05/17/2006

A

4,061

05/17/2007(2)

05/16/2016

Common Shares

4,061

$ 0 (1)

4,061

D

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
BLACKBURN MARK A 518 E. BROAD STREET COLUMBUS, OH 43215		X	Senior Vice President

Signatures

Mark A. Blackburn by John R. Lowther, attorney in fact pursuant to a POA filed with the Commission on 3-8-00		07/20/2006
**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)	field should be left blank, but due to a software defect, requires input.
(2)	The options vest in three equal installments beginning on May 17, 2007.
(3)	Includes the following acquisitions: 27.241 shares acquired in December 2004, 45.237 shares acquired in March 2005, 51.224 shares acquired in June 2005, 44.973 shares acquired in September 2005, 31.937 shares acquired in December 2005, 41.452 shares acquired in March 2006 and 37.172 shares acquired in June 2006 through the STFC 401(K) Stock Purchase Plan.
(4)	Includes the following acquisitions: 10.633 shares acquired in January 2006, 11.677 shares acquired in March 2006 and 12.981 shares acquired in June 2006 under the dividend reinvestment feature of the STFC Employee Stock Purchase Plan; and 0.093 shares acquired in January 2006, 0.115 shares acquired in March 2006 and 0.12 shares acquired in June 2006 under the STFC Dividend Reinvestment Plan.
(5)	Includes the following acquistions: 302.400 shares acquired in May 2006 through the State Auto Financial Corporation Employee Stock Purchase Plan.

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