NOTIFICATION OF MAJOR INTEREST IN SHARES

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

BTG PLC

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 notification obligation: iii

Invesco Limited

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 reached: v

17 November 2009

6. Date on which issuer notified:

18 November 2009

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

23%, 24%

8. Notified details:

A: Voting rights attached to shares viii, ix

Class/type of shares

if possible using the ISIN CODE

Situation previous to the triggering transaction

Resulting situation after the triggering transaction

Number of Shares

Number of Voting Rights

Number of shares

Number of voting rights

% of voting rights x

Direct

Direct xi

Indirect xii

Direct

Indirect

Ordinary 10p Shares

59,259,484

59,259,484

63,011,102

24.46%

GB0001001592

B: Qualifying Financial Instruments

Resulting situation after the triggering transaction

Type of financial instrument

Expiration date xiii

Exercise/ Conversion Period xiv

Number of voting rights that may be acquired if the instrument is exercised/ converted.

% of voting rights

C: Financial Instruments with similar economic effect to Qualifying Financial Instruments xv, xvi

Resulting situation after the triggering transaction

Type of financial instrument

Exercise price

Expiration date xvii

Exercise/ Conversion period xviii

Number of voting rights instrument refers to

% of voting rights xix, xx

Nominal

Delta

Total (A+B+C)

Number of voting rights

Percentage of voting rights

63,011,102

24.46%

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

Bank of Ireland (Dublin) - 1,175,349

Bank of New York - 53,617,146

Bank of New York (Brussels) - 84,767

Boston Safe Deposit - 152,947

Chase Bank - 364,722

JP Morgan Chase - 807,598

Mellon Bank (Pittsburgh) - 309,612

State Street Trust & Banking Co (London) - 6,206,090

Trust & Custody Services JP - 13,896

Northern Trust Company (London) - 278,975

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:

Andy Burrows

15. Contact telephone number:

020 7575 1714