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* DIDION JAMES J (Last) (First) (Middle) HIGHWAY 50 & AEROJET ROAD (Street) RANCHO CORDOVA CA 95670 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol GENCORP INC [ GY ]	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) 11/30/2004
	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

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
Stock Options (Right to buy)	$7.73	10/28/2004		G		7,075	08/05/2003	02/05/2013	Common Stock	7,075	(2)	0	D
Stock Options Right to buy)	$10.92	10/28/2004		G		5,085	08/06/2004	02/06/2014	Common Stock	5,085	(2)	0	D
Stock Options (Right to buy)	$14	10/28/2004		G		4,630	01/02/2003	01/02/2012	Common Stock	4,630	(2)	0	D
Phantom Stock Unit	(3)	10/28/2004		G		10,284.341(4)	(5)	(6)	Common Stock	10,284.341	(2)	0	I	By Plan
Stock Options (Right to buy)	$14	10/28/2004		G	4,630		01/02/2003	01/02/2012	Common Stock	4,630	(2)	4,630	I	By Trust
Stock Options (Right to buy)	$7.73	10/28/2004		G	7,075		08/05/2003	02/05/2013	Common Stock	7,075	(2)	7,075	I	By Trust
Stock Options (Right to buy)	$10.92	10/28/2004		G	5,085		08/06/2004	02/06/2014	Common Stock	5,085	(2)	5,085	I	By Trust
Phantom Stock Unit	(3)	10/28/2004		G	10,284.341		(5)	(6)	Common Stock	10,284.341	(2)	10,284.341	I	By Trust

Explanation of Responses:

1. On October 28, 2004, Mr. Didion transferred all GenCorp stock options and his entire interest in the GenCorp Deferred Compensation Plan for Nonemployee Directors, including Phantom Stock Units, to the Didion Trust (James J. Didion and Gloria K. Didion, Trustees).

2. Due to the nature of this transaction (i.e. a gift), the Price of the Derivative Security is not relevant to this transaction.

3. These Derivative Securities are Phantom Stock Units in the GenCorp Deferred Compensation Plan for Nonemployee Directors. The Phantom Stock Units are payable in cash upon a future date elected by the Director at the time of deferral, based upon the market value of GenCorp common shares at the time of payment. Therefore, there is no Conversion or Exercise Price for these Derivative Securities.

4. Since Mr. Didion's last reporting of Phantom Stock Units, 87.341 shares have been added to his balance. These shares include Phantom Stock Units acquired under the Dividend Reinvestment Plan in the Deferred Compensation Plan for Nonemployee Directors on 11-30-03, 2-27-04 and 5-28-04.

5. Under the terms of the GenCorp Deferred Compensation Plan for Nonemployee Directors, there is no Exercisable Date for Phantom Stock Units.

6. Under the terms of the GenCorp Deferred Compensation Plan for Nonemployee Directors, there is no Expiration Date for Phantom Stock Units.

Remarks:

	Mark A. Whitney as Attorney-in-Fact for James J. Didion	01/14/2005
	** Signature of Reporting Person	Date
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