Holding(s) in Company

TR-1: Notifications of Major Interests in Shares 1. Identity of the issuer or the Oxford Instruments PLC underlying issuer of existing shares to which voting rights are attached: 2: Reason for notification (yes/no) An acquisition or disposal of voting rights yes An acquisition or disposal of qualifying financial instruments which no may result in the acquisition of shares already issued to which voting rights are attached An acquisition or disposal of instruments with similar economic no effect to qualifying financial instruments An event changing the breakdown of voting rights no Other (please specify): no 3. Full name of person(s) subject to the Kames Capital notification obligation: 4. Full name of shareholder(s) (if different from 3.): 5. Date of the transaction (and date on 19th October 2012 which the threshold is crossed or reached): 6. Date on which issuer notified: 23rd October 2012 7. Threshold(s) that is/are crossed or 5% reached: 8: Notified Details A. Voting rights attached to shares * Class/type of share If possible GB0006650450 use ISIN code Situation previous to the triggering transaction * Number of shares * Number of voting rights 2,772,850 2,772,850 Resulting situation after the triggering transaction * Number of Number of voting rights Percentage of shares voting rights Direct Indirect Direct Indirect 1,803,391 1,803,391 932,258 3.21% 1.66% B. Qualifying Financial Instruments Resulting situation after the triggering transaction Type of Expiration Exercise/ No. of voting Percentage of financial date conversion rights that may voting rights instrument period/date be acquired (if the instrument exercised/ converted) C: Financial Instruments with similar economic effect to Qualifying Financial Instruments Resulting situation after the triggering transaction Type of financial Exercise Expiration Exercise/ Number of % of voting instrument price date Conversion voting rights period rights instrument refers to Nominal Delta Contract for Difference 75,524 0.13% 1 Total (A+B+C) Number of voting rights Percentage of voting rights 2,811,173 5.00% 9. Chain of controlled undertakings through which the voting rights and/or the financial instruments are effectively held, if applicable: Kames Capital:- Kames Capital plc Kames Capital Management Ltd Kames Capital ICVC Kames Capital VCIC Proxy Voting: 10. Name of the proxy holder: Kames Capital 11. Number of voting rights proxy holder will cease to hold: 12. Date on which proxy holder will cease to hold voting rights: 13. Additional information: 14. Contact name: Susan Johnson-Brett, Company Secretary 15. Contact telephone number: 01865 393324
UK 100