Holding(s) in Company

NOTIFICATION OF MAJOR INTERESTS IN SHARES

1.   Identity of the issuer or the underlying issuer of existing shares to     
     which voting rights are attached:                                         
                                                                               
     Johnson Matthey plc                                                       
                                                                               
2.   Reason for the notification:                                              
                                                                               
     An acquisition or disposal of voting rights                               
     An acquisition or disposal of instruments with similar economic effect to 
     qualifying instruments                                                    
                                                                               
3.   Full name of person(s) subject to the notification obligation:            
                                                                               
     BlackRock, Inc.                                                           
                                                                               
4.   Full name of shareholder(s) (if different from 3.):                       
                                                                               
     N/A                                                                       
                                                                               
5.   Date of the transaction (and date on which the threshold is crossed or    
     reached if different):                                                    
                                                                               
     19 May 2010                                                               
                                                                               
6.   Date on which issuer notified:                                            
                                                                               
     21 May 2010                                                               
                                                                               
7.   Threshold(s) that is/are crossed or reached:                              
                                                                               
     Holding has gone below 12%                                                
                                                                               
8.   Notified details:                                                         
                                                                               
A.   VOTING RIGHTS ATTACHED TO SHARES:                                         
                                                                               
     Class/type of shares (if possible using the ISIN CODE): GB0004764071 
                                                                               
     Situation previous to the triggering transaction:                         
     Number of shares: 25,236,582                                              
     Number of voting rights: 25,236,582                                       
                                                                               
     Resulting situation after the triggering transaction:                     
     Number of shares (direct): N/A                                            
     Number of voting rights (direct): N/A                                     
     Number of voting rights (indirect): 25,058,443                            
     % of voting rights (direct): N/A                                          
     % of voting rights (indirect): 11.67%                                     
                                                                               
B    QUALIFYING FINANCIAL INSTRUMENTS                                          
                                                                               
     N/A                                                                       
                                                                               
C    FINANCIAL INSTRUMENTS WITH SIMILAR ECONOMIC EFFECT TO QUALIFYING FNIANCIAL
     INSTRUMENTS                                                               
                                                                               
     Type of financial instrument: CFD                                          
     Exercise price: N/A                                                        
     Expiration date: N/A                                                      
     Exercise/Conversion period: N/A                                           
     Number of voting rights instrument refers to: 467,339                     
     % of voting rights (Nominal): 0.22%                                       
     % of voting rights (Delta): 0.22%                                         
     Total voting rights: 25,525,782 shares (11.89%)                           
                                                                               
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 - 25,525,782 shares (11.89%) 
                                                                               
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:                                                             
                                                                               
15.  Angela Purtill, Deputy Company Secretary, Johnson Matthey plc             
     Contact Telephone Number: 020 7269 8461                                   

24 May 2010