Exhibit 21.1

NYSE EURONEXT SUBSIDIARIES AND AFFILIATES

Name	State/Jurisdiction of Incorporation
NYSE Group, Inc.1	Delaware
New York Stock Exchange LLC2	New York
NYSE Market, Inc.3	Delaware
NYSE Regulation, Inc.3	New York
Stock Clearing Corporation3	New York
Newex Corporation3	New York
Newin Corporation3	New York
Securities Industry Automation Corporation3	New York
NYSE TransactTools, Inc.4	New York
Archipelago Holdings, Inc.2	Delaware
Archipelago Trading Services, Inc.5	Florida
Archipelago Direct, L.L.C.5	Delaware
NYSE Arca, L.L.C.5	Delaware
Archipelago Market Data Services, L.L.C.5	Delaware
Archipelago Securities, L.L.C.5	Delaware
NYSE Arca Holdings, Inc.5	Delaware
NYSE Arca, Inc.6	Delaware
NYSE Arca Equities, Inc.7	Delaware
TransactTools, Inc.2	Delaware
Pacific Board of Trade7	California
FINRA/NYSE Trade Reporting Facility LLC8	Delaware
Wombat Financial Software, Inc.9	Nevada
Harco Technology Ltd.10	England
Wombat Financial Software Europe Limited10	Northern Ireland
Amsterdam Merger Sub, LLC1	Delaware
American Stock Exchange LLC11*	Delaware
Amex ETF Services LLC12*	Delaware
American Stock Exchange Clearing LLC12*	Delaware
PDR Services LLC12*	Delaware
Amex Commodities LLC12*	Delaware

* Indicates an entity that is not currently a subsidiary of NYSE Euronext, but that will be a subsidiary of NYSE Euronext following NYSE Euronext’s acquisition of The Amex Membership Corporation.

¹ Wholly owned subsidiary of NYSE Euronext

² Wholly owned subsidiary of NYSE Group, Inc.

³ Wholly owned subsidiary of New York Stock Exchange LLC

⁴ Wholly owned subsidiary of Securities Industry Automation Corporation

⁵ Wholly owned subsidiary of Archipelago Holdings, Inc.

⁶ Wholly owned subsidiary of NYSE Arca Holdings, Inc.

⁷ Wholly owned subsidiary of NYSE Arca, Inc.

⁸ Wholly owned subsidiary of NYSE Market, Inc.

⁹ Wholly owned subsidiary of TransactTools, Inc.

¹⁰ Wholly owned subsidiary of Wombat Financial Software, Inc.

¹¹ Wholly owned subsidiary of Amsterdam Merger Sub, LLC

¹² Wholly owned subsidiary of American Stock Exchange LLC

Name	State/Jurisdiction of Incorporation
Amex International LLC12*	Delaware
American Stock Exchange Realty Associates LLC12*	Delaware
Amex Realty Manager, Inc.13*	Delaware
Amex Realty Borrower, LLC14*	Delaware
Seamount Execution Services LLC15*	Delaware
Seamount Trading LLC12*	Delaware
NYSE Euronext (International) B.V.1	Netherlands
NYSE Euronext (Holding) N.V.16	Netherlands
Euronext N.V.17	Netherlands
Euronext Amsterdam N.V.18	Netherlands
Euronext France S.A.S.18	France
Euronext Brussels S.A./N.V.19	Belgium
Euronext Lisbon – Sociedade Gestora de Mercados Regulamentados, S.A.18	Portugal
Euronext IFCS BVBA18	Belgium
Euronext Paris S.A.20	France
BlueNext S.A.21	France
Euronext Holdings UK Ltd.22	United Kingdom
Euronext UK Ltd.23	United Kingdom
TransactTools Ltd.23	United Kingdom
Archipelago Europe, Ltd.23	United Kingdom
Euronext Indices B.V.24	Netherlands
Euronext Amsterdam International B.V.24	Netherlands
Euronext Amsterdam Clearing & Depository N.V.24	Netherlands
Euronext Amsterdam Intermediary B.V.25	Netherlands
Euronext Real Estate S.A./N.V.26	Belgium
Interbolsa – Sociedade Gestora de Sistemas de Liquidaçao e de Sistemas Centralizados de Valores Mobilarios, S.A.27	Portugal
Financière Montmartre28	France
S.E.P.B. S.A.29	France
La Financière Événement29	France
Euronext London Limited29	United Kingdom
LIFFE (Holdings) plc30	United Kingdom

¹³ Wholly owned subsidiary of American Stock Exchange Realty Associates LLC

¹⁴ 99.99% owned by American Stock Exchange Realty Associates LLC and 0.01% owned by Amex Realty Manager, Inc.

¹⁵ Wholly owned subsidiary of Seamount Trading LLC

¹⁶ Wholly owned subsidiary of NYSE Euronext (International) B.V.

¹⁷ 97% owned subsidiary of NYSE Euronext (Holding) N.V.

¹⁸ Wholly owned subsidiary of Euronext N.V.

¹⁹ 80% owned subsidiary of Euronext N.V.; 19% owned subsidiary of Euronext Paris S.A.; 1% owned subsidiary of Euronext Lisbon – Sociedade Gestora de Mercados Regulamentados, S.A.

²⁰ Wholly owned subsidiary of Euronext France S.A.S.

²¹ 60% owned by Euronext Paris S.A.

²² Wholly owned subsidiary of Euronext N.V.

²³ Wholly owned subsidiary of Euronext Holdings UK Ltd.

²⁴ Wholly owned subsidiary of Euronext Amsterdam N.V.

²⁵ Wholly owned subsidiary of Euronext Amsterdam Clearing & Depository N.V.

²⁶ 99.84% owned by Euronext Brussels S.A./N.V. and 0.16% owned by Euronext Paris S.A.

²⁷ Wholly owned subsidiary of Euronext Lisbon – Sociedade Gestora de Mercados Regulamentados, S.A.

²⁸ 55.77% owned subsidiary of Euronext Paris S.A.

²⁹ Wholly owned subsidiary of Euronext Paris S.A.

³⁰ Wholly owned subsidiary of Euronext UK Ltd.

Name	State/Jurisdiction of Incorporation
The London Commodity Exchange 1986 Limited31	United Kingdom
Swapsconnect Ltd31	United Kingdom
CScreen Ltd31	United Kingdom
LIFFE Ventures Inc.31	United States
LIFFE Ventures II Inc.31	United States
Secfinex Limited32	United Kingdom
NQLX LLC33	United States
LIFFE Futures plc31	United Kingdom
The London Futures and Options Exchange Limited31	United Kingdom
LIFFE Nominees Limited31	United Kingdom
LIFFE USA Limited31	United Kingdom
LIFFE Development Limited31	United Kingdom
LIFFE Services Limited31	United Kingdom
The Baltic Futures Exchange31	United Kingdom
B.F.E. Debenture Company No. 1 Limited31	United Kingdom
LIFFE Options plc31	United Kingdom
LIFFE Limited31	United Kingdom
LIFFE Trustees Limited31	United Kingdom
London Traded Options Market Limited31	United Kingdom
LIFFE Administration & Management31	United Kingdom
Hugin Group B.V.34	Netherlands
Hugin SAS35	France
Hugin AS35	Norway
Hugin Norge AS36	Norway
Hugin Online A/S36	Denmark
Hugin ForetaksFakta AB36	Sweden
Hugin Investor Relations Services OY36	Finland
Hugin AG36	Switzerland
Hugin IR Services Deutschland GmbH36	Germany
Hugin (U.K.) Ltd.36	United Kingdom
Hugin IR Services B.V.36	Netherlands
Directnews AG36	Germany

³¹ Wholly owned subsidiary of LIFFE (Holdings) plc

³² 51% owned by LIFFE (Holdings) plc

³³ 98% owned subsidiary of LIFFE Ventures Inc.; 2% owned subsidiary of LIFFE Ventures II Inc.

³⁴ Wholly owned by Euronext France S.A.S.

³⁵ Wholly owned subsidiary of Hugin Group B.V.

³⁶ Wholly owned subsidiary of Hugin AS