Exhibit 21

As
of 12/31/03

LIST OF SUBSIDIARIES OF CHIRON CORPORATION

|SUBSIDIARY                                    |                     | JURISDICTION OF INCORPORATION OR ORGANIZATION                                                                                   
|--------------------------------------------- | ------------------- | --------------------------------------------------------------------------------------------------------------------------------
|Cetus Generic Corporation                     |                     | Delaware, USA                                                                                                                   
|Chiron Partners, Inc.                         |                     | California, USA                                                                                                                 
|Chiron Alpha Corporation                      |                     | California, USA                                                                                                                 
|Chiron/Cephalon JV (50%)                      |                     | Delaware, USA                                                                                                                   
|Chiron Properties, Inc.                       |                     | California, USA                                                                                                                 
|Chiron Delta Corporation                      |                     | Delaware, USA                                                                                                                   
|Chiron Investment Corporation                 |                     | Nevada, USA                                                                                                                     
|Chiron Mimotopes U.S.                         |                     | California, USA                                                                                                                 
|Chiron Redevelopment Corporation              |                     | Missouri, USA                                                                                                                   
|Chiron Foreign Sales Corporation              |                     | U.S. Virgin Islands                                                                                                             
|Biocent Insurance Company, Inc.               |                     | Hawaii, USA                                                                                                                     
|Chiron AB                                     |                     | Sweden                                                                                                                          
|Chiron Vision Canada, Inc.                    |                     | Canada                                                                                                                          
|Chiron Behring Vaccines Private Limited (51%) |                     | India                                                                                                                           
|Chiron Technologies Pty. Ltd.                 |                     | Australia                                                                                                                       
|Chiron B-1 Limited1                           |                     | Bermuda                                                                                                                         
|Chiron Overseas Holding Co.                   |                     | Nevada, USA                                                                                                                     
|                                              | Chiron B-2 Limited1 |                                                                                                                                 
|                                              |                     | Chiron Blood Testing (Bermuda) Ltd. (Originally formed as a limited liability company; converted into a partnership on 12/18/02)
|                                              |                     | PathoGenesis PortugalProdutos Farmacêuticos, Sociedade Unipessoal Lda.                                                         
|                                              |                     | Chiron Corporation Limited                                                                                                      
|                                              |                     | Chiron B.V.                                                                                                                     
|                                              |                     |                                                                                                                                 
|                                              |                     |                                                                                                                                 
|                                              |                     | Chiron Canada ULC/Chiron Canada SRI                                                                                             
|                                              |                     | Chiron Italia S.r.l                                                                                                             
|                                              |                     | Chiron France S.A.S.                                                                                                            
|                                              |                     | Chiron Blood Testing S.a.r.l.                                                                                                   
|                                              |                     | Chiron Limited                                                                                                                  
|                                              |                     | Chiron UK-1 Limited (Formerly known as "Alnery No 2339 Limited", name changed effective May 9, 2003)                            
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|                         |                                                        |                                                                                                                                                                                    |                                                                       |                                                            | PowderChek Diagnostics Inc. |                          | United States (Delaware)
|------------------------ | ------------------------------------------------------ | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------------- | ---------------------------------------------------------- | --------------------------- | ------------------------ | ------------------------
|                         |                                                        |                                                                                                                                                                                    |                                                                       | SBL Vaccin AB                                              |                             | Sweden                  
|                         |                                                        |                                                                                                                                                                                    |                                                                       |                                                            | Vitec AB                    |                          | Sweden                  
|                         |                                                        |                                                                                                                                                                                    |                                                                       | PowderJect Technologies Ltd.                               |                             | United Kingdom          
|                         |                                                        |                                                                                                                                                                                    |                                                                       | PowderJect Therapeutics Inc.                               |                             | United States (Delaware)
|PowderJect Vaccines Inc. |                                                        | United States (Delaware)                                                                                                                                                          
|                         | Chiron Healthcare Ireland Limited dba "Chiron Ireland" |                                                                                                                                                                                    | Ireland                                                              
|                         |                                                        | Chiron Blood Testing Pty Ltd                                                                                                                                                       |                                                                       | Australia                                                 
|                         | Appold Consultadoria E Serviços Lda                    |                                                                                                                                                                                    | Portugal                                                             
|                         |                                                        | Chiron Holding LLC (Formerly known as "Chiron LLC")                                                                                                                                |                                                                       | Delaware                                                  
|                         |                                                        | Chiron Hungary Üzleti Szolgáltató Korlátolt Felelösségü Társaság (aka Chiron Hungary Kft.) or Chiron Hungary Business Services Limited Liability Company (aka Chiron
Hungary Ltd)2 |                                                                       | Hungary                                                   
|                         |                                                        | Chiron Vaccines Holding Srl (formerly known as "Ami' Centro Srl")3                                                                                                                 |                                                                       | Italy                                                     
|                         |                                                        |                                                                                                                                                                                    | Chiron Srl (formerly known as S.p.A.)                                 |                                                            | Italy                      
|                         |                                                        |                                                                                                                                                                                    |                                                                       | Istituto Vaccinogeno Pozzi Srl (formerly known as S.p.A.). |                             | Italy                   
|                         |                                                        |                                                                                                                                                                                    | Chiron Funding LLC (0.01%)                                            |                                                            | Delaware, USA              
|                         |                                                        |                                                                                                                                                                                    | Chiron Corp. s.r.o. [75%; Chiron Vaccines International & Co KG, 25%] |                                                            | Czech Republic             
|                         |                                                        | Chiron Vacccines International Srl & Co KG (formerly known as "Chiron Redevelopment Corp. & Co. KG")                                                                               |                                                                       | Germany                                                   
|                         |                                                        |                                                                                                                                                                                    |                                                                       | 31. Corsa Verwaltungsgesellschaft mbH                      |                             | Germany                 
|                         |                                                        |                                                                                                                                                                                    |                                                                       | Chiron Behring Verwaltungsgesellschaft mbH                 |                             | Germany                 
|                         |                                                        |                                                                                                                                                                                    |                                                                       | Chiron Behring GmbH & Co4                                  |                             | Germany                 
|                         |                                                        |                                                                                                                                                                                    |                                                                       | Chiron GmbH                                                |                             | Germany                 
|                         |                                                        | Chiron Investment Company Spain, Srl (ETVE)                                                                                                                                        |                                                                       | Spain                                                     
|Chiron Iberia S.L.       |                                                        | Spain                                                                                                                                                                             

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