Orbital ATK, Inc., a global leader in aerospace and defense technologies, today marks its first full day of operations following the completion yesterday of the merger between Orbital Sciences Corporation and the Aerospace and Defense Groups of Alliant Techsystems Inc. The merger brings into existence a new $4.5 billion* space, defense and aviation systems manufacturer that employs more than 12,000 people in 20 states across the U.S. Shares of the new company will begin trading on the New York Stock Exchange under the ticker symbol “OA” when markets open later today.

“As separate enterprises, Orbital and ATK each established proud legacies as customer-focused companies known for innovation and affordability,” said Orbital ATK President and CEO David W. Thompson. “Now, with our two organizations coming together under the Orbital ATK banner, we begin operations with substantially greater technical and industrial capabilities and increased financial resources. Orbital ATK's commitment is to provide our customers with reliable and affordable products and systems that enable them to successfully carry out their most critical missions in aerospace and defense applications. Likewise, we are committed to delivering long-term value to our shareholders as we focus on realizing the maximum synergies created by the merger and capitalizing on a broader spectrum of new market opportunities than we could have addressed as independent companies.”

Headquartered in Dulles, Virginia, Orbital ATK will conduct its business in three operating groups that serve customers in the U.S. government, commercial and international markets:

• Flight Systems Group – Headquartered in Chandler, Arizona, the Flight Systems Group (FSG) designs, manufactures, tests and operates space launch vehicles, rocket propulsion systems, missile defense systems and advanced aerospace structures. FSG employs approximately 4,500 people and operates major facilities in Arizona, Utah, Virginia, Ohio, Alabama and Mississippi.

• Defense Systems Group – The Defense Systems Group (DSG) is headquartered in Baltimore, Maryland, and supplies advanced missile products, defense electronic systems, armament systems and small caliber ammunition systems to U.S. military and allied defense customers. DSG employs approximately 4,900 people and operates major facilities in Maryland, West Virginia, Virginia, Missouri, Minnesota, California, Arizona, Texas and Florida.

• Space Systems Group – Based in Dulles, Virginia, the Space Systems Group (SSG) focuses on commercial communications and imaging satellites; national security, scientific and human exploration spacecraft; space components and subsystems; and space-related technical services. SSG employs approximately 2,700 people and operates major facilities in Virginia, Maryland, California, Arizona, Texas and Utah.

Blake E. Larson, Orbital ATK's Chief Operating Officer, said, “The Orbital ATK team is ready to support our customers' critical defense, space and aviation missions. As we begin operations of the new company, the many years of close collaboration and similar technical approaches to development, production and testing give us a head start on combined operations. No matter the business area, we are all united to deliver operational excellence for our customers and shareholders.”