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 issuer                                      
of existing shares to which voting rights are                           Avacta Group PLC
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                     Rock Island Investments Ltd
notification obligation:iii                                                             
                                                                                        
4. Full name of shareholder(s)                                                          
 (if different from 3.):iv                                                              
                                                                                        
5. Date of the transaction and date on                                                  
which the threshold is crossed or                            27 August 2010             
reached: v                                                                              
                                                                                        
6. Date on which issuer notified:                            31 August 2010             
                                                                                        
7. Threshold(s) that is/are crossed or                       4%                         
reached: vi, vii                                                                        
                                                                                        


 

8. Notified details:                                                                      
                                                                                          
A: Voting rights attached to shares viii, ix                                              
                                                                                          
Class/   Situation previous           Resulting situation after the triggering transaction
type of  to the triggering                                                                
shares   transaction                                                                      
                                                                                          
                                                                                          
if       Number           Number      Number     Number of voting    % of  voting rights x
possible of               of          of shares  rights                                   
using    Shares           Voting                                                          
the ISIN                  Rights                                                          
CODE                                                        Indirect                      
                                      Direct     Direct xi  xii      Direct  Indirect     
                                                                                          
                                                                                          
Ordinary                                                                                  
0.1p                                                                                      
shares   66,514,131       66,514,131  63,014,131 63,014,131          4.39%                
                                                                                          
                                                                                          
                                                                                          
                                                                                          
                                                                                          
B: Qualifying Financial Instruments                                                       
                                                                                          
Resulting situation after the triggering transaction                                      
                                                                                          
Type of      Expiration    Exercise/              Number of voting          % of voting   
financial    date xiii     Conversion Period xiv  rights that may be        rights        
instrument                                        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    Exercise price Expiration Exercise/   Number of voting      % of voting rights 
financial                 date xvii  Conversion  rights instrument     xix, xx            
instrument                           period      refers to                                
                                     xviii                                                
                                                                                          
                                                                                          
                                                                       Nominal Delta      
                                                                                          
                                                                                          
                                                                                          
                                                                                          
                                                                                          
Total (A+B+C)                                                                             
                                                                                          
Number of voting rights                      Percentage of voting rights                  
                                                                                          
63,014,131                                   4.39%                                        
                                                                                          

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