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
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 Liffe LLC3a	Delaware
NYSE Liffe Holdings LLC1	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
FINRA/NYSE Trade Reporting Facility LLC8	Delaware
Wombat Financial Software, Inc.9	Delaware
Harco Technology Ltd.10	England
Wombat Financial Software Europe Limited10	Northern Ireland
NYSE Alternext US, LLC2	Delaware
Amex ETF Services LLC11	Delaware
American Stock Exchange Clearing LLC11	Delaware
PDR Services LLC11	Delaware
Amex Commodities LLC11	Delaware
Amex International LLC11	Delaware
American Stock Exchange Realty Associates LLC11	Delaware

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

^3a Wholly owned subsidiary of NYSE Liffe Holdings 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 NYSE Alternext US, LLC

Name	State/Jurisdiction of Incorporation
Amex Realty Manager, Inc.12	Delaware
Amex Realty Borrower, LLC13	Delaware
Seamount Execution Services LLC14	Delaware
Seamount Trading LLC11	Delaware
NYSE Euronext (International) B.V.1	Netherlands
NYSE Euronext (Holding) N.V.15	Netherlands
Euronext N.V.16	Netherlands
Euronext Amsterdam N.V.17	Netherlands
Euronext France S.A.S.17	France
Euronext Brussels S.A./N.V.18	Belgium
Euronext Lisbon – Sociedade Gestora de Mercados Regulamentados, S.A.17	Portugal
Euronext IFCS BVBA17	Belgium
Euronext Paris S.A.19	France
BlueNext S.A.20	France
Euronext Holdings UK Ltd.17	United Kingdom
Euronext UK Ltd.21	United Kingdom
TransactTools Ltd.21	United Kingdom
Archipelago Europe, Ltd.21	United Kingdom
Euronext Indices B.V.22	Netherlands
Euronext Amsterdam International B.V.22	Netherlands
Euronext Amsterdam Clearing & Depository N.V.22	Netherlands
Euronext Amsterdam Intermediary B.V.23	Netherlands
Euronext Real Estate S.A./N.V.24	Belgium
Interbolsa – Sociedade Gestora de Sistemas de Liquidaçao e de Sistemas Centralizados de Valores Mobilarios, S.A.25	Portugal
S.E.P.B. S.A.19	France
La Financière Événement19	France
Euronext London Limited19	United Kingdom
LIFFE (Holdings) plc26	United Kingdom

¹² Wholly owned subsidiary of American Stock Exchange Realty Associates LLC

¹³ 99.99% owned by American Stock Exchange Realty Associates LLC and 0.01% owned by Amex Realty Manager, Inc.

¹⁴ Wholly owned subsidiary of Seamount Trading LLC

¹⁵ Wholly owned subsidiary of NYSE Euronext (International) B.V.

¹⁶ 99.35% owned subsidiary of NYSE Euronext (Holding) N.V.; 0.62% owned by Euronext Paris S.A., 0.03% owned by Euronext N.V.

¹⁷ Wholly owned subsidiary of Euronext N.V.

¹⁸ 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.

¹⁹ Wholly owned subsidiary of Euronext France S.A.S.

²⁰ 60% owned by Euronext Paris S.A.

²¹ Wholly owned subsidiary of Euronext Holdings UK Ltd.

²² Wholly owned subsidiary of Euronext Amsterdam N.V.

²³ Wholly owned subsidiary of Euronext Amsterdam Clearing & Depository N.V.

²⁴ 99.84% owned subsidiary of Euronext Brussels S.A./N.V. and 0.16% are owned by Euronext Paris S.A.

²⁵ Wholly owned subsidiary of Euronext Lisbon – Sociedade Gestora de Mercados Regulamentados, S.A.

²⁶ Wholly owned subsidiary of Euronext UK Ltd.

Name	State/Jurisdiction of Incorporation
The London Commodity Exchange 1986 Limited27	United Kingdom
Swapsconnect Ltd27	United Kingdom
CScreen Ltd27	United Kingdom
LIFFE Ventures Inc.27	Delaware
LIFFE Ventures II Inc.27	Delaware
Secfinex Limited28	United Kingdom
NQLX LLC29	Delaware
LIFFE Futures plc27	United Kingdom
The London Futures and Options Exchange Limited27	United Kingdom
LIFFE Nominees Limited27	United Kingdom
LIFFE USA Limited27	United Kingdom
LIFFE Development Limited27	United Kingdom
LIFFE Services Limited27	United Kingdom
The Baltic Futures Exchange27	United Kingdom
B.F.E. Debenture Company No. 1 Limited27	United Kingdom
LIFFE Options plc27	United Kingdom
LIFFE Limited27	United Kingdom
LIFFE Trustees Limited27	United Kingdom
London Traded Options Market Limited27	United Kingdom
LIFFE Administration & Management27	United Kingdom
Hugin Group B.V.19	Netherlands
Hugin SAS30	France
Hugin AS30	Norway
Hugin Norge AS31	Norway
Hugin Online A/S31	Denmark
Hugin ForetaksFakta Online AB31	Sweden
Hugin Investor Relations Services OY31	Finland
Hugin AG31	Switzerland
Hugin IR Services Deutschland GmbH31	Germany
Hugin (U.K.) Ltd.31	United Kingdom
Hugin IR Services B.V.31	Netherlands
Hugin Germany AG31	Germany
Imperium Centre Limited32	United Kingdom
SmartPool Holdings Limited33a	United Kingdom
SmartPool Trading Limited33	United Kingdom
NYSE Euronext Technology Holding S.A.S.34	France
Atos Euronext Market Solutions Inc.35	New York
NYSE Euronext Technology IPR Ltd.35	United Kingdom
NYSE Euronext Technology Ltd.35	United Kingdom
NYSE Euronext Technology S.A.S.35	France
NYSE Euronext Technology B.V.35	Netherlands
NYSE Euronext Technology S.A./N.V.35	Belgium
Prime Source (NYSE Euronext) Limited27	United Kingdom

²⁷ Wholly owned subsidiary of LIFFE (Holdings) plc

²⁸ 51% owned by LIFFE (Holdings) plc

²⁹ 98% owned subsidiary of LIFFE Ventures Inc.; 2% owned subsidiary of LIFFE Ventures II Inc.

³⁰ Wholly owned subsidiary of Hugin Group B.V.

³¹ Wholly owned subsidiary of Hugin AS

³² Wholly-owned subsidiary of Euronext Holdings UK Ltd

³³ Wholly owned subsidiary of SmartPool Holding Limited

^33a 72.83% owned by Euronext Holdings UK Ltd

³⁴ 50% owned subsidiary of Euronext France S.A.S., 32.72% owned subsidiary of LIFFE Administration and Management., 15.55% owned subsidiary of Euronext Paris S.A. and 1.73% owned subsidiary of Euronext Amsterdam N.V.

³⁵ Wholly owned by NYSE Euronext Technology Holding S.A.S.