Vesuvius Regulatory News (VSVS)

TR-1: NOTIFICATION OF MAJOR INTERESTS IN SHARES

1. Identity of the issuer or the underlying issuer of existing shares to which voting rights are attached:

COOKSON GROUP PLC

2. Reason for the notification (please state Yes/No):

An acquisition or disposal of voting rights: ( Yes )

An acquisition or disposal of financial instruments which may result in the acquisition of shares already issued to which voting rights are attached: ( )

An event changing the breakdown of voting rights: ( )

Other (please specify): (  )

3. Full name of person(s) subject to the notification obligation:

Adage Capital Partners GP LLC

4. Full name of shareholder(s) (if different from 3.):

JP Morgan Custodial Trust Company and Morgan Stanley & Co.

5. Date of the transaction (and date on which the threshold is crossed or reached if different):

8 February 2010

6. Date on which issuer notified:

10 February 2010

7. Threshold(s) that is/are crossed or reached:

3%

8. Notified details:

……………..

A: Voting rights attached to shares

Resulting situation after the triggering transaction

B: Financial Instruments

Resulting situation after the triggering transaction

 C: Financial Instruments with similar economic effect to Qualifying Financial instruments

Resulting situation after the triggering transaction

Total (A+B+C)

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

JP Morgan Custodial Trust Company and Morgan Stanley & Co. are the custodians of the shares held by Adage Custodial Partners GP LLC.

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:

RACHEL FELL, DEPUTY SECRETARY, COOKSON GROUP PLC

15. Contact telephone number:

+ 44 (0) 20 7822 0000