TR-1: NOTIFICATION OF MAJOR INTEREST IN SHARES
1. Identity of the issuer or the underlying issuerof existing shares to which voting rights areattached:
Tullow Oil 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 thenotification obligation:
Commonwealth Bank of Australia on behalf of the controlled undertaking;
First State Investments (UK) Limited
First State Investments (Singapore)
First State Investments International Limited
Realindex Investments Pty Limited
4. Full name of shareholder(s) (if different from 3.):
5. Date of the transaction and date onwhich the threshold is crossed orreached:
3rd December 2015
6. Date on which issuer notified:
7th December 2015
7. Threshold(s) that is/are crossed orreached:
>3%
8. Notified details:
A: Voting rights attached to shares
Class/type ofshares
if possible usingthe ISIN CODE
Situation previousto the triggeringtransaction
Resulting situation after the triggering transaction
NumberofShares
NumberofVotingRights
Numberof shares
Number of votingrights
% of voting rights x
Direct
Indirect
25,062,619
28,054,427
3.08%
GB0001500809
B: Qualifying Financial Instruments
Type of financialinstrument
Expirationdate
Exercise/Conversion Period
Number of votingrights that may beacquired if theinstrument isexercised/ converted.
% of votingrights
C: Financial Instruments with similar economic effect to Qualifying Financial Instruments
Exercise price
Expiration date
Exercise/Conversion period
Number of voting rights instrument refers to
% of voting rights
Nominal
Delta
Total (A+B+C)
Number of voting rights
Percentage of voting rights
9. Chain of controlled undertakings through which the voting rights and/or thefinancial instruments are effectively held, if applicable:
First State Investments (UK) Limited - 16,626,532 - 1.82%
First State Investments (Singapore) - 11,030,339 - 1.21%
First State Investments International Limited - 332,810 - 0.04%
Realindex Investments Pty Limited - 64,746 - 0.01%
Proxy Voting:
10. Name of the proxy holder:
11. Number of voting rights proxy holder will ceaseto hold:
12. Date on which proxy holder will cease to holdvoting rights:
13. Additional information:
Please be advised 911,570,410 was used as the denominator
14. Contact name:
Kevin Massie
Corporate Counsel & Deputy Company Secretary
Tullow Oil Plc
15. Contact telephone number:
020 3249 9000