RNS Number:2266N
Isotron PLC
7 July 2003


                    BLOCKLISTING SIX MONTHLY REVIEW


1. NAME OF COMPANY:

   ISOTRON PLC


2. NAME OF SCHEME:

   1994 EXECUTIVE SHARE OPTION SCHEME


3. PERIOD OF RETURN:     FROM:            TO:

                         1 JANUARY 2003   30 JUNE 2003


4. NUMBER AND CLASS OF SHARES(S)
   (AMOUNT OF STOCK/DEBT SECURITY)
   NOT ISSUED UNDER SCHEME
   AT END OF THE LAST PERIOD:

   165,500


5. NUMBER OF SHARES ISSUED/ALLOTTED
   UNDER SCHEME DURING PERIOD:

   -


6. BALANCE UNDER SCHEME NOT YET ISSUED/ALLOTTED 
   AT END OF PERIOD:

   165,500


7. NUMBER AND CLASS OF SHARE(S) 
   (AMOUNT OF STOCK/DEBT SECURITIES) 
   ORIGINALLY LISTED AND THE DATE OF ADMISSION:

   200,000
   REF:  A/4933/1997
   12 DECEMBER 1997

PLEASE CONFIRM TOTAL NUMBER OF SHARES IN ISSUE AT THE END OF THE PERIOD
IN ORDER FOR US TO UPDATE OUR RECORDS.

   21,070,005

CONTACT FOR QUERIES

NAME:                    MRS C BRAY

TELEPHONE:               01793 567900


                      This information is provided by RNS
            The company news service from the London Stock Exchange

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