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EXHIBIT 21

INTERNATIONAL BUSINESS MACHINES CORPORATION SUBSIDIARIES

Subsidiaries—as of December 31, 2010

Company Name	State or country of incorporation or organization	Voting percent owned directly or indirectly by registrant
IBM Argentina Sociedad Anonima	Argentina		100.00
IBM Australia Limited	Australia		100.00
IBM Oesterreich Internationale Bueromaschinen Gesellschaft m.b.H.	Austria		100.00
IBM Bahamas Limited	Bahamas		100.00
IBM Foreign Sales Corporation	Barbados		100.00
International Business Machines of Belgium sprl/buba	Belgium		100.00
WTC Insurance Corporation, Ltd.	Bermuda		100.00
IBM de Bolivia, S.A.	Bolivia		100.00
IBM Brasil—Industria, Maquinas e Servicos Limitada	Brazil		100.00
IBM Bulgaria Ltd.	Bulgaria		100.00
IBM Canada Limited—IBM Canada Limitee	Canada		100.00
IBM Tchad SARLU	Chad		100.00
IBM de Chile S.A.C.	Chile		100.00
IBM (China) Investment Company Limited	China (P.R.C.)		100.00
IBM de Colombia & C.I.A. S.C.A.	Colombia		100.00
IBM RDC	Congo Republic		100.00
IBM Business Transformation Center, S.r.l.	Costa Rica		100.00
IBM Croatia Ltd./IBM Hrvatska d.o.o.	Croatia		100.00
IBM Ceska Republika spol. s.r.o.	Czech Republic		100.00
IBM Danmark A/S	Denmark		100.00
IBM del Ecuador, C.A.	Ecuador		100.00
IBM Egypt Business Support Services	Egypt		100.00
IBM Eesti Osauhing (IBM Estonia Ou)	Estonia		100.00
Oy International Business Machines AB	Finland		100.00
Compagnie IBM France, S.A.S.	France		100.00
IBM Deutschland GmbH	Germany		100.00
International Business Machines Ghana Limited	Ghana		100.00
IBM Hellas Information Handling Systems S.A.	Greece		100.00
IBM China/Hong Kong Limited	Hong Kong		100.00
IBM Magyarorszagi Kft.	Hungary		100.00
IBM India Private Limited	India		100.00
PT IBM Indonesia	Indonesia		100.00
IBM Ireland Limited	Ireland		100.00
IBM Ireland Product Distribution Limited	Ireland		100.00
IBM Israel Limited	Israel		100.00
IBM Italia S.p.A.	Italy		100.00
IBM Japan, Ltd.	Japan		100.00
IBM East Africa Limited	Kenya		100.00
IBM Korea, Inc.	Korea (South)		100.00
Sabiedriba ar irobezotu atbildibu IBM Latvija	Latvia		100.00
IBM Lietuva	Lithuania		100.00
IBM Services Financial Sector Luxembourg Sarl	Luxembourg		100.00
International Business Machines Madagascar SARLU	Madagascar		100.00
International Information Services Management Limited	Malawi		100.00
IBM Malaysia Sdn. Bhd.	Malaysia		100.00
IBM Malta Limited	Malta		100.00

Company Name	State or country of incorporation or organization	Voting percent owned directly or indirectly by registrant
International Business Machines (Mauritius)	Mauritius		100.00
IBM de Mexico, S. de R.L.	Mexico		99.99	(A)
IBM Maroc	Morocco		100.00
IBM International Group B.V.	Netherlands		100.00
IBM International Holdings B.V.	Netherlands		100.00
IBM Nederland B.V.	Netherlands		100.00
IBM New Zealand Limited	New Zealand		100.00
IBM Niger SARLU	Niger		100.00
International Business Machines West Africa Limited	Nigeria		100.00
International Business Machines AS	Norway		100.00
IBM del Peru, S.A.	Peru		100.00
IBM Philippines, Incorporated	Philippines		100.00
IBM Polska Sp.z.o.o.	Poland		100.00
Companhia IBM Portuguesa, S.A.	Portugal		100.00
IBM Romania Srl	Romania		100.00
IBM East Europe/Asia Ltd.	Russia		100.00
IBM—International Business Machines d.o.o., Belgrade	Serbia		100.00
International Information Services Management Limited	Seychelles		100.00
IBM Limited	Sierra Leone		100.00
IBM Singapore Pte. Ltd.	Singapore		100.00
IBM Slovensko spol s.r.o.	Slovak Republic		100.00
IBM Slovenija d.o.o.	Slovenia		100.00
IBM South Africa (Pty) Ltd.	South Africa		100.00
International Business Machines, S.A.	Spain		100.00
International Busines Machines Svenska A.B.	Sweden		100.00
IBM Schweiz AG—IBM Suisse SA—IBM Suizzera SA—IBM Switzerland Ltd.	Switzerland		100.00
IBM Taiwan Corporation	Taiwan		100.00
IBM Tanzania Limited	Tanzania		100.00
IBM Thailand Company Limited	Thailand		99.99	(A)
IBM Tunisie	Tunisia		100.00
IBM (International Business Machines) Turk Limited Sirketi	Turkey		100.00
Technology Products and Services Limited	Uganda		100.00
IBM Ukraine	Ukraine		100.00
IBM Middle East FZ—LLC	United Arab Emirates		100.00
IBM United Kingdom Limited	United Kingdom		100.00
IBM del Uruguay, S.A.	Uruguay		100.00
IBM Capital Inc.	USA (Delaware)		100.00
IBM Credit LLC	USA (Delaware)		100.00
IBM International Group Capital LLC	USA (Delaware)		100.00
IBM International Foundation	USA (Delaware)		100.00
IBM World Trade Corporation	USA (Delaware)		100.00
IBM de Venezuela, S.A.	Venezuela		100.00
IBM Vietnam Company	Vietnam		100.00
International Business Machines Zambia Limited	Zambia		100.00

(A)

Minor percentage held by other IBM shareholders subject to repurchase option.

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EXHIBIT 21

INTERNATIONAL BUSINESS MACHINES CORPORATION SUBSIDIARIES