OA Orbital Atk, Inc. (delisted)

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PART I — REGISTRANT INFORMATION

PART II — RULES 12b-25(b) AND (c)

If the subject report could not be filed without unreasonable effort or expense and the registrant seeks relief pursuant to Rule 12b-25(b), the following should be completed. (Check box if appropriate)

PART III — NARRATIVE

State below in reasonable detail why Forms 10-K, 20-F, 11-K, 10-Q, 10-D, N-SAR, N-CSR, or the transition report or portion thereof, could not be filed within the prescribed time period.

Orbital ATK, Inc. (the “Company”) is unable to file its Annual Report on Form 10-K for the year ended December 31, 2016 (the “2016 Form 10-K”) within the prescribed time period without unreasonable effort or expense because of the circumstances described below .

As reported in the Company’s Current Reports on Form 8-K filed on August 10, 2016 and November 3, 2016, the Audit Committee of the Board of Directors of the Company, after considering the recommendation of management, concluded that the Company’s previously issued financial statements for the nine-month transition period ended December 31, 2015 (“2015 transition period”), fiscal year ended March 31, 2015 (“fiscal 2015”), fiscal year ended March 31, 2014 (“fiscal 2014”), and fiscal year ended March 31, 2013 (“fiscal 2013”), and the quarters in each period (except for the first quarter of 2013) and the quarter ended April 3, 2016, should no longer be relied upon as a result of misstatements in such financial statements.

The Company filed an amendment to the Transition Report on Form 10-K for the 2015 transition period (the “Form 10-K/A”) on February 24, 2017, in which it restated its consolidated financial statements for the 2015 transition period, fiscal 2015, fiscal 2014, the unaudited quarterly information in the 2015 transition period and fiscal 2015 and the unaudited selected financial data contained in the Form 10-K/A. The misstatement corrections contained in the restated financial statements collectively are referred to as the “Restatement.” An explanation of the underlying cause of the Restatement is included in the above referenced Form 10-K/A.

The Company expects to file a Form 10-Q/A for the quarter ended April 3, 2016 (the “Form 10-Q/A”), which will include restated consolidated financial statements for that period and the comparative period as soon as practical. Thereafter, the Company expects to file a Form 10-Q for each of the quarters ended July 3, 2016 and October 2, 2016 (collectively, the “2016 Forms 10-Q”). After it has filed the Form 10-Q/A and the 2016 Forms 10-Q, the Company expects to file its 2016 Form 10-K.

In view of the resources that were focused on the preparation of the Form 10-K/A that was recently filed and the ongoing work in preparing the Form 10-Q/A, the 2016 Forms 10-Q and 2016 Form 10-K, the Company will not be able to without unreasonable effort or expense file its 2016 Form 10-K by March 16, 2017, which is the deadline for the extended filing period pursuant to Rule 12b-25.

As previously disclosed, the Company has entered into an extension agreement with its credit agreement lenders to extend to April 14, 2017 the deadline under its credit agreement for filing with the SEC the 2016 Form 10-K, as well as the Form 10-Q/A and 2016 Forms 10-Q.

Forward Looking Statements

Certain matters discussed in this filing constitute forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. These forward-looking statements are based on management’s current beliefs, assumptions and expectations regarding future events, which in turn are based on information currently available to management. Such forward-looking statements include the timing of the filing of the Form 10-Q/A, the 2016 Forms 10-Q and the 2016 Form 10-K . The Company cautions you not to place undue reliance on any such forward-looking statements. Several factors could cause actual results to differ materially from those expressed in or contemplated by the forward-looking statements. Such factors include, but are not limited to, the fact that the Company is continuing to prepare the Form 10-Q/A, the 2016 Forms 10-Q and the 2016 Form 10-K, the risk that additional information may arise or different conclusions are reached prior to the expected filing with the SEC of the contemplated filings, the preparation of the Company’s restated financial statements or other subsequent events that would require us to make additional adjustments, as well as inherent limitations in internal controls over financial reporting. Other risk factors affecting the Company are discussed in detail in the Company’s filings with the SEC, including in the Form 10-K/A. The Company undertakes no obligation to publicly update or revise any forward-looking statement, whether as a result of new information, future events or otherwise, except as may be required by law.