EXHIBIT 21
SUBSIDIARIES OF THE REGISTRANT
<Table>
<Caption>
STATE OF
NAME OF ENTITY INCORPORATION SUBSIDIARY OF WHAT ENTITY
- --------------------------------------------------------------- ------------------ -----------------------------------------------
Ingenix, Inc. Delaware UnitedHealth Group Incorporated
Reden & Anders, Ltd. Minnesota Ingenix, Inc.
Subrogation Advantage, Ltd. Minnesota Ingenix, Inc.
Ingenix Publishing, Inc. Delaware Ingenix, Inc.
Ingenix Health Intelligence, L.L.C. Delaware Ingenix Publishing, Inc.
Ingenix Pharmaceutical Services, Inc. Delaware Ingenix, Inc.
Ingenix International (Canada), Inc. Canada Ingenix Pharmaceutical Services, Inc.
Ingenix Services, Inc. Delaware Ingenix Pharmaceutical Services, Inc.
Ingenix Pharmaceutical Services (Deutschland) GmbH Germany Ingenix Pharmaceutical Services, Inc.
Ingenix International (Hong Kong) Limited Hong Kong Ingenix Pharmaceutical Services, Inc.
Ingenix Pharmaceutical Services Holdings, Inc. Delaware Ingenix Pharmaceutical Services, Inc.
ClinPharm International Limited United Kingdom Ingenix Pharmaceutical Services Holdings, Inc.
Ingenix Pharmaceutical Services (UK) Limited United Kingdom ClinPharm International Limited
Ingenix Pharmaceutical Services (Spain) SL Spain Ingenix Pharmaceutical Services (UK) Limited
Ingenix Pharmaceutical Services (Australia) Pty Ltd Australia Ingenix Pharmaceutical Services (UK) Limited
Ingenix International (Italy) s.r.l. Italy Ingenix Pharmaceutical Services (UK) Limited
ClinPharm International SARL France Ingenix Pharmaceutical Services (UK) Limited
Worldwide Clinical Trials SARL France ClinPharm International SARL
Ingenix Pharmaceutical Services, LLC Delaware Ingenix Pharmaceutical Services Holdings, Inc.
InSite Clinical Trials LLC Delaware Ingenix Pharmaceutical Services Holdings, Inc.
CT Management, Inc. California Ingenix Pharmaceutical Services Holdings, Inc.
ICT (UK) Limited United Kingdom Ingenix Pharmaceutical Services Holdings, Inc.
Ingenix International (Australia) Pty Limited Australia Ingenix Pharmaceutical Services Holdings, Inc.
Ingenix International (Netherlands) BV Netherlands Ingenix Pharmaceutical Services Holdings, Inc.
Ingenix Pharmaceutical Services (Sweden) AB Sweden Ingenix Pharmaceutical Services Holdings, Inc.
Ingenix Pharmaceutical Services de Argentina S.R.L. Argentina Ingenix Pharmaceutical Services Holdings, Inc.
Ingenix International (Czech Republic), s.r.o. Czechoslovakia Ingenix Pharmaceutical Services Holdings, Inc.
Worldwide Clinical Trials, SL Spain Ingenix Pharmaceutical Services Holdings, Inc.
Ingenix International (Hungary) Ltd. Hungary Ingenix Pharmaceutical Services Holdings, Inc.
Ingenix Pharmaceutical Services (RSA) Proprietary Limited South Africa Ingenix Pharmaceutical Services Holdings, Inc.
Ingenix International (Finland) Oy Finland Ingenix Pharmaceutical Services Holdings, Inc.
Ingenix International (UK) Limited United Kingdom Ingenix Pharmaceutical Services Holdings, Inc.
UnitedHealthcare International Asia, LLC Delaware UnitedHealth Group Incorporated
UnitedHealthcare International Malaysia Sdn. Bhd. Malaysia UnitedHealthcare International Asia, LLC
UnitedHealthcare Asia Limited Hong Kong UnitedHealthcare International Asia, LLC
United HealthCare (Deutschland) GmbH Germany UnitedHealth Group Incorporated
Philam Care Health Systems, Inc. Philippines UnitedHealth Group Incorporated
AIG United HealthCare LLC Delaware UnitedHealth Group Incorporated
AIA United HealthCare Limited Hong Kong AIG United HealthCare LLC
H&W Indemnity, Ltd. Caymans UnitedHealth Group Incorporated
UHC International Holdings, Inc. Delaware UnitedHealth Group Incorporated
UHC International Services, Inc. Delaware UnitedHealth Group Incorporated
UnitedHealthcare International Inc. Delaware UnitedHealth Group Incorporated
United Healthcare International Mauritius Limited Maruitius UnitedHealth Group Incorporated
Sedgewick Parekh Health Management (Private) Limited India United Healthcare International Mauritius Limited
UnitedHealth Group Finance Company, Inc. Delaware UnitedHealth Group Incorporated
Asia Services, LLC Delaware UnitedHealth Group Finance Company, Inc.
Ovations, Inc. Delaware United HealthCare Services, Inc.
Evercare of New York, IPA, Inc. New York Ovations, Inc.
Optage, LLC Delaware Ovations, Inc.
The Ovations Press, Inc. Delaware Ovations, Inc.
The Ovations Press/Wurman, L.L.C. Delaware The Ovations Press, Inc.
Lifemark Corporation Delaware Ovations, Inc.
Arizona Health Concepts, Inc. Arizona Lifemark Corporation
</Table>
Page 1 of 3
EXHIBIT 21
SUBSIDIARIES OF THE REGISTRANT
<Table>
<Caption>
STATE OF
NAME OF ENTITY INCORPORATION SUBSIDIARY OF WHAT ENTITY
- --------------------------------------------------------------- ------------------ -----------------------------------------------
Evercare at Home, Inc. Arizona Lifemark Corporation
Evercare of Arizona, Inc. Arizona Lifemark Corporation
Evercare Connections, Inc. Delaware Lifemark Corporation
Lifemark Care Management, Inc. Delaware Lifemark Corporation
Lifemark Government Services, LLC Indiana Lifemark Care Management, Inc.
Lifemark New York, Inc. Delaware Lifemark Corporation
Lifemark at Home NY, Inc. New York Lifemark Corporation
MCS HP New York, LLC New York Lifemark Corporation
Evercare of Texas, L.L.C. Texas Lifemark Corporation
Lifemark Healthplans of Delaware, Inc. Delaware Lifemark Corporation
Uniprise, Inc. Delaware United HealthCare Services, Inc.
United HealthCare Service Corp. New York Uniprise, Inc.
United HealthCare (Ireland) Limited Ireland Uniprise, Inc.
Charter Oak HealthCare Services, Inc. Delaware Uniprise, Inc.
United Healthcare Services, Inc. Minnesota UnitedHealth Group Incorporated
UnitedHealthcare, Inc. Delaware United HealthCare Services, Inc.
United HealthCare of Alabama, Inc. Alabama United HealthCare, Inc.
United HealthCare of Arizona, Inc. Arizona United HealthCare, Inc.
Arizona Physicians IPA, Inc. Arizona United HealthCare of Arizona, Inc.
United HealthCare of Arkansas, Inc. Arkansas United HealthCare, Inc.
United HealthCare of Colorado, Inc. Colorado United HealthCare, Inc.
United HealthCare of Florida, Inc. Florida United HealthCare, Inc.
United HealthCare of Georgia, Inc. Georgia United HealthCare, Inc.
United HealthCare of Illinois, Inc. Delaware United HealthCare, Inc.
United HealthCare of Louisiana, Inc. Louisiana United HealthCare, Inc.
United HealthCare of the Mid-Atlantic, Inc. Maryland United HealthCare, Inc.
United HealthCare of the Midlands, Inc. Nebraska United HealthCare, Inc.
United HealthCare of the Midwest, Inc. Missouri United HealthCare, Inc.
United HealthCare of Mississippi, Inc. Mississippi United HealthCare, Inc.
United HealthCare of Nevada, Inc. Nevada United HealthCare, Inc.
United HealthCare of New Jersey, Inc. New Jersey United HealthCare, Inc.
United HealthCare of New York, Inc. New York United HealthCare, Inc.
United HealthCare of North Carolina, Inc. North Carolina United HealthCare, Inc.
United HealthCare of Tennessee, Inc. Tennessee United HealthCare, Inc.
United HealthCare of Texas, Inc. Texas United HealthCare, Inc.
United HealthCare of Utah Utah United HealthCare, Inc.
United HealthCare of Wisconsin, Inc. Wisconsin United HealthCare, Inc.
United HealthCare Network, Inc. Alabama United HealthCare, Inc.
United HealthCare of Upstate New York, Inc. New York United HealthCare, Inc.
Unified Limited United Kingdom United HealthCare Services, Inc.
United HealthCare of New England, Inc. Rhode Island United HealthCare Services, Inc.
United HealthCare of Ohio, Inc. Ohio United HealthCare Services, Inc.
United HealthCare of Oregon, Inc. Oregon United HealthCare Services, Inc.
United HealthCare Plans of Puerto Rico, Inc. Puerto Rico United HealthCare Services, Inc.
United HealthCare Networks, Inc. Delaware United HealthCare Services, Inc.
UnitedHealth Capital, LLC Delaware United HealthCare Services, Inc.
Commonwealth Physicians Services Corporation Kentucky United HealthCare Services, Inc.
United HealthCare of Minnesota, Inc. Minnesota United HealthCare Services, Inc.
United HealthCare of Washington, Inc. Washington United HealthCare Services, Inc.
UnitedHealth Financial Services, Inc. Delaware United HealthCare Services, Inc.
Exante Bank, Inc. Utah UnitedHealth Financial Services, Inc.
United HealthCare of Kentucky, Ltd. Kentucky United HealthCare Services, Inc.
</Table>
Page 2 of 3
EXHIBIT 21
SUBSIDIARIES OF THE REGISTRANT
<Table>
<Caption>
STATE OF
NAME OF ENTITY INCORPORATION SUBSIDIARY OF WHAT ENTITY
- --------------------------------------------------------------- ------------------ ----------------------------------------------
Specialized Care Services, Inc. Delaware United HealthCare Services, Inc.
Optum Group, LLC Delaware Specialized Care Services, Inc.
Coordinated Vision Care, Inc. Delaware Specialized Care Services, Inc.
Coordinated Vision Care of New York, IPA, Inc. New York Coordinated Vision Care, Inc.
Unimerica Insurance Company Maryland Specialized Care Services, Inc.
United Resource Networks, Inc. Delaware Specialized Care Services, Inc.
Specialty Resource Services, Inc. Delaware United Resource Networks, Inc.
National Benefit Resources, Inc. Minnesota Specialized Care Services, Inc.
Stop-Loss Life Reinsurance Company Arizona National Benefit Resources, Inc.
Spectera, Inc. Maryland Specialized Care Services, Inc.
Spectera Vision Services of California, Inc. California Specialized Care Services, Inc.
Spectera Vision Services of Florida, Inc. Florida Specialized Care Services, Inc.
Spectera Insurance Company Maryland Specialized Care Services, Inc.
Spectera Eyecare of North Carolina, Inc. North Carolina Specialized Care Services, Inc.
Spectera Insurance Company, Inc. Texas Specialized Care Services, Inc.
Spectera Vision, Inc. Virginia Specialized Care Services, Inc.
Group Vision Associates, Inc. Pennsylvania Specialized Care Services, Inc.
American Chiropractic Network, Inc. Minnesota United HealthCare Services, Inc.
Managed Physical Network, Inc. New York American Chiropractic Network, Inc.
Managed Physical Network IPA of New York, Inc. New York American Chiropractic Network, Inc.
American Chiropractic Network IPA of New York, Inc. New York American Chiropractic Network, Inc.
Dental Benefit Providers, Inc. Delaware United HealthCare Services, Inc.
Dental Benefit Providers of California, Inc. California Dental Benefit Providers, Inc.
Dental Benefit Providers of Illinois, Inc. Illinois Dental Benefit Providers, Inc.
Dental Benefit Providers of New Jersey, Inc. New Jersey Dental Benefit Providers, Inc.
Dental Insurance Company of America New York Dental Benefit Providers, Inc.
DBP-KAI, Inc. New York Dental Benefit Providers, Inc.
Dental Benefit Providers of Maryland, Inc. Maryland Dental Benefit Providers, Inc.
Dental Benefit Services of Illinois, Inc. (non-profit) Illinois Dental Benefit Providers, Inc.
United Behavioral Health California United HealthCare Services, Inc.
U.S. Behavioral Health Plan, California (Knox Keene) California United Behavioral Health
Behavioral Health Administrators California United Behavioral Health
United Behavioral Health of New York, I.P.A., Inc. New York United Behavioral Health
Working Solutions, Inc. Oregon United Behavioral Health
Unimerica, Inc. Delaware United HealthCare Services, Inc.
United HealthCare Insurance Company (Ins.) Connecticut Unimerica, Inc.
Clarite, LLC United HealthCare Insurance Company (Ins.)
The MetraHealth Employee Benefits Company, Inc. United HealthCare Insurance Company (Ins.)
The MetraHealth Care Network, Inc. The MetraHealth Employee Benefits Company, Inc.
MetraHealth Care Management Corporation Delaware United HealthCare Insurance Company (Ins.)
United HealthCare of California, Inc. California MetraHealth Care Management Corporation
United HealthCare Insurance Company of Illinois (Ins.) Illinois United HealthCare Insurance Company (Ins.)
United HealthCare Insurance Company of New York (Ins.) New York United HealthCare Insurance Company (Ins.)
United HealthCare Insurance Company of Ohio (Ins.) Ohio United HealthCare Insurance Company (Ins.)
United HealthCare Life Insurance Company of New York New York United HealthCare Insurance Company (Ins.)
United HealthCare Products, LLC Delaware United HealthCare Insurance Company (Ins.)
United HealthCare Service LLC Delaware United HealthCare Insurance Company (Ins.)
</Table>
Page 3 of 3