SEC Form 4

FORM 4		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 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: 3235-0287 Estimated average burden hours per response: 0.5
X	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person* THOMPSON DAVID W (Last) (First) (Middle) C/O ORBITAL SCIENCES CORPORATION 45101 WARP DRIVE (Street) DULLES VA 20166 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol ORBITAL SCIENCES CORP /DE/ [ ORB ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) X Director 10% Owner X Officer (give title below) Other (specify below) Chairman, President and CEO
	3. Date of Earliest Transaction (Month/Day/Year) 02/09/2015
	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 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	01/07/2014		G		2,000	D	$0	223,511	D
Common Stock	02/19/2014		G		750	D	$0	222,761	D
Common Stock	02/26/2014		G		500	D	$0	222,261	D
Common Stock	03/19/2014		G		500	D	$0	221,761	D
Common Stock	06/09/2014		G		500	D	$0	221,261	D
Common Stock	06/23/2014		G		1,000	D	$0	220,261	D
Common Stock	08/14/2014		G		1,000	D	$0	219,261	D
Common Stock	09/02/2014		G		1,000	D	$0	218,261	D
Common Stock	09/24/2014		G		500	D	$0	217,761	D
Common Stock	01/26/2015		G		1,000	D	$0	216,761	D
Common Stock(1)	02/09/2015		A		30,000	A	$0(2)	246,761	D
Common Stock	02/09/2015		D		246,761	D	(3)	0	D
Common Stock	02/09/2015		D		22,600	D	(4)	0	I	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)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. Grant of Restricted Stock Units under the issuer's Amended and Restated 2005 Stock Incentive Plan that vest one-half the day after the closing of the Merger (as defined in the Transaction Agreement) and one-half one year thereafter.

2. The reporting person received the Restricted Stock Units in connection with his employment for no monetary consideration.

3. Represents 118,481 shares of common stock disposed of pursuant to the Transaction Agreement among Alliant Techsystems, Inc. (renamed Orbital ATK, Inc.) ("Orbital ATK"), Vista Merger Sub Inc., Vista Outdoor Inc. (formerly known as Vista SpinCo Inc.) and Orbital Sciences Corporation ("Orbital") (the "Transaction Agreement"), pursuant to which each share of Orbital common stock was converted into 0.449 shares of Orbital ATK common stock and cash payable in lieu of fractional shares and 128,280 Restricted Stock Units disposed of pursuant to the Transaction Agreement whereby each Restricted Stock Unit of Orbital was converted into 0.449 Restricted Stock Units of Orbital ATK with the same vesting schedule, resulting in 53,197 shares of Orbital ATK common stock and 57,597 Restricted Stock Units of Orbital ATK, each at a market value of $63.94 based on the opening price per share of Orbital ATK common stock on the first trading day following the Merger.

4. Represents 22,600 shares of common stock disposed of pursuant to the Transaction Agreement, pursuant to which each share of Orbital common stock was converted into 0.449 shares of Orbital ATK common stock and cash payable in lieu of fractional shares of Orbital ATK common stock, resulting in 10,147 shares of Orbital ATK common stock at a market value of $63.94 based on the opening price per share of Orbital ATK common stock on the first day of trading following the Merger.

	/s/ James S. Black II, Attorney-in-Fact	02/11/2015
	** 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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