HGG.L Regulatory News (HGG)

TR-1: NOTIFICATION OF MAJOR INTEREST IN SHARES

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

Henderson Group 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:

Silchester International Investors LLP

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

Silchester International Investors International Value Equity Taxable Trust

Silchester International Investors International Value Equity Trust

Silchester International Investors International Value Equity Group Trust

Silchester International Investors Tobacco Free International Value Equity Trust

The Calleva Trust

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

13th February 2017

6. Date on which issuer notified:

14th February 2017

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

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

Direct

Direct

Indirect

Direct

Indirect

JE00B3CM9527

56,204,113

56,204,113

56,661,381

5.01%

Ordinary Shares

B: Qualifying Financial Instruments

Resulting situation after the triggering transaction

Type of financialinstrument

Expirationdate i

Exercise/Conversion Period

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

% of votingrights

N/A

N/A

N/A

N/A

N/A

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

N/A

N/A

N/A

N/A

N/A

Nominal

Delta

N/A

N/A

Total (A+B+C)

Number of voting rights

Percentage of voting rights

56,661,381

5.01%

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

N/A

Proxy Voting:

10. Name of the proxy holder:

Silchester International Investors LLP

11. Number of voting rights proxy holder will cease to hold:

N/A

12. Date on which proxy holder will cease to hold voting rights:

N/A

13. Additional information:

Silchester International Investors LLP ("Silchester") acts as investment manager for the clients detailed in Question 4 above (our "Clients"). In acting for our Clients, Silchester are given full discretion over their investments and are empowered to vote on their behalf. However, we do not act as our Clients' custodian and therefore shares are not held in our name but in the name of each Client's custodian bank.

The change in Silchester's holdings was due to a series of transactions over a series of different trading days. Details of the number of shares held before the change (shown in Section A) represent the shares held by Silchester's clients immediately before the date of triggering this Notice of Substantial Shareholder's Interest (a notification of crossing 5% of the company's voting rights) and not as of the last trading day before which this disclosure was triggered.

Notification is provided based on a total voting rights figure of 1,131,842,109.

14. Contact name:

Timothy J. Linehan, Chief Compliance Officer

15. Contact telephone number:

0207 518 7125