Holding(s) in Company

For filings with the FSA include the annex For filings with issuer exclude the annex TR-1: NOTIFICATION OF MAJOR INTEREST IN SHARESi

1. Identity of the issuer or the underlying Oxford Instruments plc issuer of existing shares to which voting

rights are attached: ii

2. Reason for the notification (please tick the appropriate box or boxes):

An acquisition or disposal of voting rights x An acquisition or disposal of qualifying financial instruments which

may result in the acquisition of shares already issued to which voting rights are attached

An acquisition or disposal of instruments with similar economic effect to qualifying financial instruments

An event changing the breakdown of voting rights Other (please specify):

3. Full name of person(s) subject to The Capital Group Companies, Inc the notification obligation: iii

4. Full name of shareholder(s) (if The Capital Group Companies, Inc. ("CG") different from 3.):iv holdings: Capital Research and Management Company SMALLCAP World Fund, Inc 5. Date of the transaction and date 20th December 2012 on which the threshold is crossed or reached: v 6. Date on which issuer notified: 21st December 2012 7. Threshold(s) that is/are crossed Above 5% or reached: vi, vii

8. Notified details:

A: Voting rights attached to shares viii, ix

Class/type Situation previous Resulting situation after of to the triggering the triggering shares transaction transaction if possible Number Number % of voting using Number of Number of rights x the ISIN of Voting of voting CODE Shares Rights shares rights Indirect Direct xi Indirect Direct Indirect xii

GB0006650450 2,758,807 2,758,807 2,949,262 n/a 2,949,262 n/a 5.2459%

B: Qualifying Financial Instruments Resulting situation after the triggering transaction

Type of financial Expiration Exercise/ Number of voting % of voting

instrument date xiii Conversion Period rights that may be rights xiv acquired if the instrument is exercised/ conv erted. n/a

C: Financial Instruments with similar economic effect to Qualifying Financial Instruments xv, xvi

Resulting situation after the triggering transaction Type of Exercise Expiration Exercise/ Number of voting % of voting financial price date xvii Conversion rights instrument rights xix, xx instrument period refers to xviii Nominal Delta n/a Total (A+B+C) Number of voting rights Percentage of voting rights 2,949,262 5.2459%

9. Chain of controlled undertakings through which the voting rights and/or the financial instruments are effectively held, if applicable: xxi

The Capital Group Companies, Inc. ("CG") holdings: No. of shares % of voting rights

Capital Research and Management Company SMALLCAP World Fund, Inc 2,949,262 5.246% Proxy Voting: 10. Name of the proxy holder: 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: Oxford Instruments plc 14. Contact name: Susan Johnson-Brett 15. Contact telephone number: 01865 393 324