Holding(s) in Company

Cookson Group PLC
02 August 2006



                                  SCHEDULE 10

                   NOTIFICATION OF MAJOR INTERESTS IN SHARES

1) Name of company

COOKSON GROUP PLC


2) Name of shareholder having a major interest

AVIVA PLC AND ITS SUBSIDIARIES


3) Please state whether notification indicates that it is in respect of
holding of the shareholder named in 2 above or in respect of a
non-beneficial interest or in the case of an individual holder if it is a
holding of that person's spouse or children under the age of 18

AS IN 2 ABOVE


4) Name of the registered holder(s) and, if more than one holder, the
number of shares held by each of them

Morley Fund Management Ltd:

BNY Norwich Union Nominees Limited        2,287,400*

Chase GA Group Nominees Limited           5,146,034*

Chase Nominees Limited                      202,092*

CUIM Nominee Limited                      2,039,634*



* denotes beneficial interest


5) Number of shares/amount of stock acquired

65,845


6) Percentage of issued class

0.03%


7) Number of shares/amount of stock disposed

n/a


8) Percentage of issued class

n/a


9) Class of security

ORDINARY SHARES OF 10 PENCE EACH


10) Date of transaction

1 August 2006


11) Date company informed

2 August 2006


12) Total holding following this notification

9,675,160*

*  beneficial interest only


13) Total percentage holding of issued class following this notification

5.02%


14) Any additional information

N/A


15) Name of contact and telephone number for queries

RACHEL FELL, DEPUTY SECRETARY, COOKSON GROUP PLC - TEL: [phone]


16) Name and signature of authorised company official responsible for
making this notification

RACHEL FELL, DEPUTY SECRETARY, COOKSON GROUP PLC


Date of notification: 2 AUGUST 2006




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