Holding(s) in Company

RNS Number:4760O
Henderson Morley PLC
21 February 2008

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:

Henderson Morley Plc

2. Reason for the notification (place an X inside the appropriate bracket/s)

An acquisition or disposal of voting rights: ( x )

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:

Michael P Dunne

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

.................

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

21 February 2008

6. Date on which issuer notified:

21 February 2008

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

8. Notified details:

.................

A: Voting rights attached to shares

Class/type of shares if possible Situation previous to the Triggering transaction
using the ISIN CODE
Number of shares Number of voting Rights

GB0030711229

27,291,000 27,291,000

Resulting situation after the triggering transaction

Class/type of shares if Number of shares Number of voting rights % of voting rights
possible using the ISIN CODE

Direct Direct Indirect Direct Indirect

GB0030711229 29.791.000 29.791.000 6.06%

B: Financial Instruments

Resulting situation after the triggering transaction

Type of Expiration Date Exercise/Conversion Number of voting rights % of voting rights
financial Period/ Date that may be acquired if the
instrument instrument is exercised/
converted.

Total (A+B)
Number of voting rights % of voting rights

29.791.000 6.06%

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

.................

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: