Weir Group Regulatory News (WEIR)

TR-1: NOTIFICATION OF MAJOR INTEREST IN SHARES

1. Identity of the issuer or the underlying issuerof existing shares to which voting rights areattached:

Weir Group PLC

2 Reason for the notification (please tick the appropriate box or boxes):

An acquisition or disposal of voting rights

Yes

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

Yes

An event changing the breakdown of voting rights

Other (please specify):

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

BlackRock, Inc.

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

5. Date of the transaction and date onwhich the threshold is crossed orreached:

30th November 2010

6. Date on which issuer notified:

2nd December 2010

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

Holding has gone above 5%

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

Direct xi

Indirect xii

Direct

Indirect

GB0009465807

N/A

N/A

N/A

N/A

9,523,428

N/A

4.52%

B: Qualifying Financial Instruments

Resulting situation after the triggering transaction

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

Resulting situation after the triggering transaction

Type of financialinstrument

Exercise price

Expiration date

Exercise/Conversion period

Number of voting rights instrument refers to

% of voting rights

CFD

N/A

N/A

N/A

1,224,861

Nominal

Delta

0.58%

0.58%

Total (A+B+C)

Number of voting rights

Percentage of voting rights

10,748,289

5.10%

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

BlackRock Investment Management (UK) Limited - 10,748,289 (5.10%)

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:

BlackRock Threshold Reporting Team

14. Contact name:

Stuart Watchorn

15. Contact telephone number:

020 7743 5741