SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 _ _ _ _ _ _ _ _ _ _ _ _ FORM 6-K REPORT of Foreign Private Issuer Pursuant to Rule 13a-16 or 15d-16 of the Securities Exchange Act of 1934 For the month of: March 2003 Filtronic plc (Exact name of registrant as specified in charter) The Waterfront, Salts Mill Road, Saltaire, Shipley West Yorkshire BD18 3TT, UK (Address of principal executive offices) Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F. Form 20-F _ X _ Form 40-F _ _ _ Indicate by check mark whether the registrant by furnishing the information contained in the Form is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934 Yes _ _ _ No _ X _ <Page> SIGNATURE 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, thereunto duly authorised. Filtronic plc Date: March 14, 2003 By: /s/ Fiona Pick _ _ _ _ _ _ _ _ _ _ Name: Fiona Pick Title: Solicitor and Assistant Company Secretary SCHEDULE 10 NOTIFICATION OF MAJOR INTERESTS IN SHARES 1. Name of company Filtronic plc 2. Name of shareholder having a major interest Fidelity International Limited and certain of its Subsidiary companies, also comprising the notifiable interest of Mr Edward C Johnson 3rd, principal shareholder of Fidelity International Limited 3. Please state whether notification indicates that it I in respect of holding of the shareholder named in 2 above or in respect of a non-beneficial interest or in the case of an individual holder if it is a holding of that person's spouse or children under the age of 18 Non-beneficial interest 4. Name of the registered holder(s) and, if more than one holder, the number of shares held by each of them See attached schedule 5. Number of shares / amount of stock acquired 100,000 6. Percentage of issued class 0.1345% 7. Number of shares / amount of stock disposed N/a 8. Percentage of issued class N/a 9. Class of security Ordinary shares 10. Date of transaction 13 March 2003 11. Date company informed 14 March 2003 12. Total holding following this notification 9,687,275 13. Total percentage holding of issued class following this notification 13.0372% 14. Any additional information 15. Name of contact and telephone number for queries Fiona Pick +44 1274 231166 16. Name and signature of authorised company official responsible for making this notification Fiona Pick Date of notification 14 March 2003 Filtronic plc Schedule to Schedule 10 14 March 2003 - FIL Registered Holder Shares Held Chase Nominees Ltd 5,496,670 Chase Manhatten Bank London 10,396 Nortrust Nominees Ltd 723,680 Bankers Trust 1,053,762 MSS Nominees Ltd 68,300 BT Globenet Nominees Ltd 200,350 RBS Trust Bank 887,926 Citibank 59,850 Bank of New York London 496,551 Northern Trust 220,190 HSBC 242,000 Deutche Bank 46,500 Mellon Nominees Ltd 66,100 Bank of New York Brussels 115,000 TOTAL 9,687,275 The FSA does not give any express or implied warranty as to the accuracy of this document or material and does not accept any liability for error or omission. The FSA is not liable for any damages (including, without limitation, damages for loss of business or loss of profits) arising in contract, tort or otherwise from the use of or inability to use this document, or any material contained in it, or from any action or decision taken as a result of using this document or any such material.