1. Identity of the issuer or the underlying issuer of existing shares to which voting rights are attached:
IG Group Holdings 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 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 the notification obligation:
CANTILLON CAPITAL MANAGEMENT LLC
4. Full name of shareholder(s) (if different from 3.):
Bank of New York Mellon, State Street Bank, Northern Trust Bank, JP Morgan
5. Date of the transaction (and date on which the threshold is crossed or reached if different):
03 March 2015
6. Date on which issuer notified:
03 March 2015
7. Threshold(s) that is/are crossed or reached:
5%
8. Notified details:
A: Voting rights attached to shares
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
Direct
Direct
Indirect
Direct
Indirect
GB00B0
6QFB75
25,254,876
18,308,919
18,258,919
4.99%
B: Qualifying Financial Instruments
Resulting situation after the triggering transaction
Type of financial instrument
Expiration date
Exercise/ Conversion Period/ Date
Number of voting rights that may be acquired if the instrument is exercised/ converted.
% of voting rights
N/A
C: Financial Instruments with similar economic effect to Qualifying Financial Instruments
Resulting situation after the triggering transaction
Type of financial instrument
Exercise price
Expiration date
Exercise/conversion period
Number of voting rights instrument refers to
% of voting rights
Nominal
Delta
N/A
9. Chain of controlled undertakings through which the voting rights and/or the financial instruments are effectively held, if applicable:
William von Mueffling is the sole shareholder of Cantillon, Inc., the Corporate General Partner of Cantillon Management LP, which is the sole member of Cantillon Capital Management LLC.
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:
IG Group Holdings plc is a United Kingdom-based global financial technology company. The Company delivers online trading platforms and an educational ecosystem. The Companyâs products include OTC leveraged derivatives, exchange-traded derivatives and stock trading and investments. OTC leveraged derivatives include contracts for difference (CFDs), spread betting and options. Its exchange-traded derivatives consist of Spectrum, a multilateral trading facility (MTF). Its exchange-traded derivatives are financial contracts traded on a regulated exchange and trade its products under its tastytrade, and Spectrum Markets. The stock trading and investment offerings give traditional investors a range of non-leveraged products to choose from. The Company offers its clients access to over 19,000 financial markets through its offices spread across Europe, North America, Africa, Asia-Pacific and the Middle East.
IG GROUP HOLDINGS PLC 
