Notification of major interest in shares

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

Clarkson 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: iii

Mason Hill Advisors, LLC

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

Nortrust Nominees Limited is a nominee shareholder in respect of 104,190 shares in Clarkson PLC and Goldman Sachs International is a nominee shareholder in respect of 657,212 shares in Clarkson PLC.

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

19 April 2013

6. Date on which issuer notified:

23 April 2013

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

4%

8. Notified details:

A: Voting rights attached to shares viii, ix

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

563,402

563,402

761,402

761,402

4.01%

ORDINARY SHARES ISIN:GB002018363

B: Qualifying Financial Instruments

Resulting situation after the triggering transaction

Type of financialinstrument

Expirationdate xiii

Exercise/Conversion Period xiv

Number of votingrights that may beacquired if theinstrument isexercised/ converted.

% of votingrights

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

Resulting situation after the triggering transaction

Type of financialinstrument

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

761,402

4.01%

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

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:

Mason Hill Advisors, LLC acts as an investment manager for Equinox Partners, LP and Mason Hill Partners, LP.

Equinox Partners, LP beneficially holds 657,212 (or 3.46%) of the shares in Clarkson PLC described above and Mason Hill Partners, LP beneficially holds 104,190 (or 0.55%) of the shares in Clarkson PLC described above.

14. Contact name:

Roger Anscher

15. Contact telephone number:

+001 646 833 2788