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              BlackRock, Inc           
notification                                                                   
                                                                               
obligation:                                                                    
                                                                               
4. Full name of shareholder(s) (if                                             
different from 3.):                                                            
                                                                               
5. Date of the transaction (and date on               14 March 2012            
which the threshold                                                            
                                                                               
is crossed or reached):                                                        
                                                                               
6. Date on which issuer notified:                     16 March 2012            
                                                                               
7. Threshold(s) that is/are crossed or          Holding has gone below 16%     
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       
                                                                               
              6,597,937                               6,597,937                
                                                                               
Resulting situation after the triggering transaction                           
                                                                               
    * Number of           Number of voting rights            Percentage of     
        shares                                               voting rights     
                                                                               
                         Direct            Indirect       Direct     Indirect  
                                                                               
       n/a                n/a             7,252,451         n/a       12.92%   

 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)                    
                                                                               

1,700,191NominalDelta

C: Financial Instruments with similar economic effect to Qualifying             
Financial Instruments                                                           
                                                                                
Resulting situation after the triggering transaction                            
                                                                                
Type of          Exercise Expiration Exercise/  Number of    % of voting        
financial        price    date       Conversion voting       rights             
instrument                           period     rights                          
                                                instrument                      
                                                refers to                       
                                                                                
      CFD                                                                       
                                                                                
                                                                 3.03%     3.03%
                                                                                

Total (A+B+C)                                                                  
                                                                               
Number of voting rights                      Percentage of voting rights       
                                                                               
                 8,952,642                                 15.95%              

9. Chain of controlled undertakings through which the voting rights and/or the 
financial instruments are effectively held, if applicable:                     
                                                                               
BlackRock Investment Management (UK) Limited - 8,952,642 (15.95%)              

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:                                                    
                                                                               
14. Contact name:                     Susan Johnson-Brett, Company Secretary   
                                                                               
15. Contact telephone number:                      01865 393324