Exhibit 21 LIST OF SUBSIDIARIES
| 2089729 Ontario, Inc. |
| 2248848 Ontario Inc. |
| 3065619 Nova Scotia Company |
| 3257959 Nova Scotia Company |
| 3901858 Canada, Inc. |
| 896988 Ontario Inc. |
| 9279-3280 Quebec Inc. |
| Accupath Diagnostic Laboratories, Inc. |
| Accuro Inc. |
| Beacon Laboratory Benefit Solutions, Inc. |
| CannAmm GP Inc. |
| CannAmm Limited Partnership |
| Cellmark Forensics, Inc. |
| Centrex Clinical Laboratories, Inc. |
| Clearstone Central Laboratories (Canada) Inc. |
| Clearstone Central Laboratories (China) Inc. |
| Clearstone Central Laboratories (U.S.) Inc. |
| Clearstone Holdings (International) Ltd. |
| Clipper Holdings, Inc. |
| Colorado Coagulation Consultants, Inc. |
| Correlagen Diagnostics, Inc. |
| Cytometry Associates, Inc. |
| Czura Thornton (Hong Kong) Limited |
| DCL Acquisition, Inc. |
| DCL Medical Laboratories, LLC |
| DCL Sub LLC |
| Decision Diagnostics, LLC (aka DaVinici/Medicorp LLC) |
| Diagnostic Services, Inc. |
| DIANON Systems, Inc. |
| DL Holdings Limited Partnership |
| Dynacare - Gamma Laboratory Partnership |
| Dynacare Company |
| Dynacare G.P. Inc. |
| Dynacare Holdco LLC |
| Dynacare Laboratories Limited Partnership |
| Dynacare Laboratories Inc. |
| Dynacare Northwest Inc. |
| Dynacare Realty Inc. |
| DynaLifeDX |
| DynalifeDX Infrastructure Inc. |
| Endocrine Sciences, Inc. |
| Esoterix Genetic Counseling, LLC |
| Esoterix Genetic Laboratories, LLC |
| Esoterix, Inc. |
| Execmed Health Services Inc. |
| FirstSource Laboratory Solutions, Inc. |
| Gamma-Dynacare Central Medical Laboratories GP Inc. |
| Gamma-Dynacare Central Medical Laboratory Limited Partnership |
| GDML Medical Laboratories Inc |
| GeneScreen, Inc. |
| Glen Ames LLP |
| HHLA Lab-In-An-Envelope, LLC |
| Home Healthcare Laboratory of America, LLC |
| IDX Pathology, Inc. |
| Impact Genetics, Inc. |
| Lab Delivery Service of New York City, Inc. |
| LabCorp Dialysis Services, Inc. |
| LabCorp BVBA |
| LabCorp Clinical Trials (Singapore) Pte. Ltd. |
| LabCorp Development Company |
| LabCorp Japan, G.K. |
| LabCorp Limited |
| LabCorp Specialty Testing Billing Service, Inc. |
| LabCorp Specialty Testing Group, Inc. |
| LabCorp Tennessee, LLC |
| Laboratory Corporation of America (LCA) |
| Laboratory Corporation of America Holdings (LCAH) |
| LCAH Clipper, LP |
| LDS Diagnostic Laboratories Inc |
| Lifecodes Corporation |
| Litholink Corporation |
| MedAxio Insurance Medical Services GP Inc. |
| MedAxio Insurance Medical Services LP |
| Medtox Diagnostics, Inc. |
| Medtox Laboratories, Inc. |
| Medtox Scientific, Inc. |
| Monogram Biosciences, Inc. |
| Monogram Biosciences UK Limited |
| National Genetics Institute |
| New Brighton Business Center LLC |
| New Imaging Diagnostics, LLC |
| New Molecular Diagnostics Ventures LLC |
| NWT Inc. |
| Orchid Cellmark Ltd. |
| Orchid Cellmark ULC |
| PA Labs, Inc. |
| Path Lab Incorporated |
| Persys Technology Inc. |
| Princeton Diagnostic Laboratories of America, Inc. |
| Protedyne Corporation |
| ReliaGene Technologies, Inc. |
| Rix Ltd. |
| SW/DL LLC |
| Tandem Labs Inc. |
| The Biomarker Factory, LLC |
| United/Dynacare LLC |
| Viro-Med Laboratories, Inc. |
| Dynacare non-operating entities identified subsequent to the acquisition of Dynacare Inc. on July 25, 2002 |
| 1004679 Ontario Limited |
| 563911 Ontario Limited |
| 794475 Ontario Inc. |
| 829318 Ontario Limited |
| 854512 Ontario Limited |
| 879606 Ontario Limited |
| 900747 Ontario Ltd. |
| 925893 Ontario Limited |
| 942487 Ontario Ltd. |
| 942489 Ontario Ltd. |
| 942491 Ontario Limited |
| 942492 Ontario Ltd. |
| 947342 Ontario Ltd. |
| 949235 Ontario Ltd. |
| 958069 Ontario Inc. |
| 977681 Ontario Inc. |
| 978550 Ontario Ltd. |
| 978551 Ontario Ltd. |
| Amherstview Medical Centre Developments Inc. |
| DHG Place Du Centre Clinique |
| Dynacare Canada Inc. |
| Dynacare International Inc. |
| Glen Davis Equities Ltd. |
| L.R.C. Management Service Inc. |
| Lawrence-Curlew Medical Centre Inc. |
| Roselat Developments Limited |
| St. Joseph's Health Centre |
| Stockwin Corporation Ltd. |
| Thistle Place Care Corp. |
| Toronto Argyro Medical Laboratories Ltd. |
| Woodstock Medical Arts Building Inc. |
| Covance, Inc. Subsidiaries |
| CJB, Inc. |
| Covance (Argentina) SA |
| Covance (Asia) Pte. Ltd. |
| Covance (Canada) Inc. |
| Covance Antibody Services Inc. |
| Covance Asia-Pacific Inc. |
| Covance Bioanalytical Services Inc. |
| Covance Central Laboratory Services Limited Partnership |
| Covance Central Laboratory Services SA |
| Covance Central Laboratory Services Inc. |
| Covance Clinical and Periapproval Services AG |
| Covance Clinical and Periapproval Services GmbH |
| Covance Clinical and Periapproval Services Limited |
| Covance Clinical and Periapproval Services LLC |
| Covance Clinical and Periapproval Services SA |
| Covance Clinical and Periapproval Services SARL |
| Covance Clinical Research Unit AG |
| Covance Clinical Research Unit Inc. |
| Covance Clinical Research Unit Ltd. |
| Covance Clinical Research, L.P. |
| Covance CRU Inc |
| Covance Development Services (Pty) Ltd. |
| Covance Genomics Laboratory LLC |
| Covance Hong Kong Holdings Limited |
| Covance Hungária Consultancy Limited Liability Company |
| Covance International Holdings B.V. |
| Covance Japan Co. Ltd. |
| Covance Laboratories GmbH |
| Covance Laboratories Limited |
| Covance Laboratories Inc. |
| Covance Laboratory |
| Covance Latin America Inc. |
| Covance Limited |
| Covance Market Access Services Inc. |
| Covance Periapproval Services Inc. |
| Covance Pharmaceutical Research and Development (Beijing) Co. Ltd. |
| Covance Pharmaceutical Research and Development (Shanghai) Co. Ltd. |
| Covance (Polska) Sp.Zo. |
| Covance Preclinical Corporation |
| Covance Pty. Ltd. |
| Covance Research Holdings, LLC |
| Covance Research Products Inc. |
| Covance Specialty Pharmacy LLC |
| Texas Covance GP, Inc. |
| Covance Austria GmbH |
| Covance Brazil Pharmaceutical Services Limitada |
| Covance Chile Services Limitada |
| Covance Hong Kong Services Limited |
| Covance Classic Laboratory Services Inc. |
| Covance Clinical and Periapproval Services Limited |
| Covance Clinical Product Developments Ltd. |
| Covance Colombia Services Limitada |
| Covance Denmark Aps |
| Covance India Pharmaceutical Services Private Limited |
| Covance Korea Services Limited |
| Covance Laboratories Korea Company Limited |
| Medaxial Limited |
| Covance Services Malaysia Sdn. Bhd. |
| Covance Mexico Services, S. DE R. L. De C.V. |
| Covance New Zealand Limited |
| Covance Peru Services S.A. |
| CRPP Inc. |
| Covance Services (Thailand) Limited |
| Covance Taiwan Services Limited |
| Covance Virtual Central Laboratory B.V. |
| DKJR LLC (assumed name for SLJK LLC in Texas) |
| Fairfax Storage Limited |
| PMD Properties, LLC |
| SLJK LLC |
| REIM LLC |
| SPHN LLC |
| Hazpen Trustees Ltd |
| JSG R&D LLC |
| Nexigent Inc |