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                              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 effect    No   
to qualifying financial instruments                                            
                                                                               
An event changing the breakdown of voting rights                          No   
                                                                               
Other (please                                                             No   
specify):                                                                      

3. Full name of person(s) subject to                Kames Capital              
the notification obligation: iii                                               
                                                                               
4. Full name of shareholder(s) (if                                             
different from 3.):iv                                                          
                                                                               
5. Date of the transaction and date              16th December 2011            
on which the threshold is crossed or                                           
reached: v                                                                     
                                                                               
6. Date on which issuer notified:                20th December 2011            
                                                                               
7. Threshold(s) that is/are crossed                      3%                    
or reached: vi, vii                                                            

8. Notified details:
A: Voting rights attached to shares viii, ix

Class/type of Situation previous            Resulting situation after           
shares         to the triggering                  the triggering                
                  transaction                      transaction                  
                                                                                
if possible              Number                   Number          % of voting   
using          Number      of      Number           of             rights x     
the ISIN CODE    of      Voting      of           voting                        
               Shares    Rights    shares         rights                        
                                                                                
                                   Direct   Direct xi Indirect  Direct  Indirect
                                                        xii                     
                                                                                
GB00006650450 1,612,253 1,612,253 1,252,637 1,252,637 615,116   2.27%    1.11%  

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/                  
                                                   converted.                  
                                                                               

C: Financial Instruments with similar economic effect to Qualifying Financial  
Instruments xv, xvi                                                            
                                                                               
Resulting situation after the triggering transaction                           

Type of finan  Exercise Expiration Exercise/  Number of voting    % of voting   
     cial       price   date xvii  Conversion rights instrument  rights xix, xx 
  instrument                         period       refers to                     
                                     xviii                                      
                                                                                
                                                                Nominal   Delta 
                                                                                
 Contract for                                                               1   
  difference                                                                    

Total (A+B+C)                                                                  

        Number of voting rights               Percentage of voting rights      
                                                                               
               1,867,753                                 3.38%                 

9. Chain of controlled undertakings through which the voting rights and/or the 
financial instruments are effectively held, if applicable: xxi                 
                                                                               
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:                     Oxford Instruments plc         
                                                                               
14. Contact name:                       Susan Johnson-Brett (Company Secretary)
                                                                               
15. Contact telephone number:                        01865 393324              

Note: Annex should only be submitted to the FSA not the issuer                 
                                                                               
Annex: Notification of major interests in sharesxxii                           

A: Identity of the persons or legal entity subject to the notification
obligation

Full name                                                                      
(including legal form of legal                                                 
entities)                                                                      
                                                                               
Contact address                                                                
(registered office for legal entities)                                         
                                                                               
Phone number & email                                                           
                                                                               
Other useful information                                                       
(at least legal representative for                                             
legal persons)                                                                 

B: Identity of the notifier, if applicable

Full name                                                                      
                                                                               
Contact address                                                                
                                                                               
Phone number & email                                                           
                                                                               
Other useful information(e.g.                                                  
functional relationship with the person                                        
or legal entity subject to the                                                 
notification obligation)                                                       

C: Additional information                                                      
                                                                               

For notes on how to complete form TR-1 please see the FSA website.