Notification of Major Interest in Shares

TR-1: NOTIFICATION OF MAJOR INTEREST IN SHARESi

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

IG Group Holdings plc

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

An acquisition or disposal of voting rights

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

X

Other (please specify):

3. Full name of person(s) subject to the notification obligation: iii

CVC European Equity III Limited

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

CVC European Equity Partners III L.P.

CVC European Equity Partners III Parallel Fund -A L.P.

CVC European Equity Partners III Parallel Fund - B L.P.

CVC Europe Enterprise (Domestic) L.P.

CVC Europe Enterprise (Cayman) L.P.

5. Date of the transaction and date on which the threshold is crossed or reached: v

10 May 2010

(Note: Date for settlement is 14th May 2010).

6. Date on which issuer notified:

11 May 2010

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

From 7% to 3%

8. Notified details:

A: Voting rights attached to shares viii, ix

Class/type of shares

if possible using the ISIN CODE

Situation previous to the triggering transaction

Resulting situation after the triggering transaction

Number of Shares

Number of Voting Rights

Number of shares

Number of voting rights

% of voting rights x

Direct

Direct xi

Indirect xii

Direct

Indirect

Ordinary Shares

27,909,755

27,909,755

13,954,879

13,954,879

3.86

GB00B06QFB75

B: Qualifying Financial Instruments

Resulting situation after the triggering transaction

Type of financial instrument

Expiration date xiii

Exercise/ Conversion Period xiv

Number of voting rights that may be acquired if the instrument is exercised/ converted.

% of voting rights

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

Resulting situation after the triggering transaction

Type of financial instrument

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

13,954,879

3.86%

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

CVC European Equity III Limited is general partner of the limited partnership known as CVC

European Equity III General Partner L.P., which is the general partner of each of the limited

partnerships known as CVC European Equity Partners III L.P., CVC European Equity Partners III

Parallel Fund - A L.P. and CVC European Equity Partners III Parallel Fund - B L.P. CVC European Equity III Limited is the parent company of CVC Europe Enterprise GP Limited, which is the general partner of each of the limited partnerships known as CVC Europe Enterprise (Domestic) L.P. and CVC Europe Enterprise (Cayman) L.P.

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:

As required by DTR 5.8.8, the percentage voting rights figure used for the purposes of this notification was calculated using the number of voting rights in existence at 1 April 2010, being the date of IG Group Holdings plc's most recent disclosure made in accordance with DTR 5.6.1 ( Ordinary

Shares).

Three co-investment vehicles invested in

IG Group Holdings plc alongside the CVC funds listed above and have disposed of a proportional amount of their shareholding. These are Capital Investors 2002 Limited (disposed of 135,149 shares; new shareholding 149,383 shares), Citicorp Capital Investors Europe Limited (disposed of 671,816 shares;

new shareholding 671,815 shares); Citi

Europe Co-Invest, L.P. (disposed of 134,348

shares; new shareholding 134,347 shares) and Indigo Feeder L.P. (disposed of 192,103 shares; new shareholding 192,103). These entities are not under the control of CVC European Equity III Limited and hence have not been included in this notification.

14. Contact name:

Guy Abbi

Company Secretary

IG Group Holdings plc

15. Contact telephone number:

020 7896 0011