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SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 8-K
Current Report Pursuant to Section 13 or 15(d)
of the Securities Exchange Act of 1934
Date of Report (Date of earliest event reported): May 10, 1999
ORBITAL SCIENCES CORPORATION
Delaware 0-18287 06-1209561
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(State or other jurisdiction of (Commission File (I.R.S. Employer
incorporation or organization) Number) Identification No.)
21700 Atlantic Boulevard
Dulles, Virginia 20166
(703) 406-5000
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(Address and telephone number of principal executive offices)
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ITEM 4. CHANGES IN REGISTRANT'S CERTIFYING ACCOUNTANT.
On May 10, 1999, Orbital Sciences Corporation (the "Company") engaged
PricewaterhouseCoopers LLP ("PricewaterhouseCoopers") as its independent
auditor to audit the Company's consolidated financial statements for the year
ended December 31, 1999. During the two most recent fiscal years of the
Company, and during the subsequent interim period preceding the engagement of
PricewaterhouseCoopers, neither the Company nor anyone on its behalf has
consulted with PricewaterhouseCoopers regarding either (i) the application of
accounting principles to specified transactions, either completed or proposed,
or the type of audit opinion that might be rendered on the Company's financial
statements, or (ii) any of the matters described in the Company's Current
Report on Form 8-K dated April 29, 1999, and neither a written report nor oral
advice was provided to the Company by PricewaterhouseCoopers.
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SIGNATURES
Pursuant to the requirements of the Securities Exchange Act of 1934,
the registrant has duly caused this report to be signed on its behalf by the
undersigned hereunto duly authorized.
ORBITAL SCIENCES CORPORATION
Date: May 11, 1999 By: /s/ Jeffrey V. Pirone
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Jeffrey V. Pirone
Executive Vice President and
Chief Financial Officer
