Exhibit 21

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 (Merged into a newly-formed Nevada corporation called "Chiron Investment Corporation" on 10/29/02) |                     | California, 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                                                                                                            
|Chiron Funding Corporation (Converted into a Delaware limited liability company on 10/28/02, "Chiron Holding LLC"))              |                     | Delaware, USA                                                                                                                  
|Biocent Insurance Company, Inc.                                                                                                  |                     | Hawaii, USA                                                                                                                    
|PathoGenesis BV                                                                                                                  |                     | The Netherlands                                                                                                                
|Chiron Vision Canada, Inc.                                                                                                       |                     | Canada                                                                                                                         
|Chiron Behring Vaccines Private Limited (51%)                                                                                    |                     | India                                                                                                                          
|Chiron Vision Canada, Inc.                                                                                                       |                     | Canada                                                                                                                         
|Chiron B-1 Limited (formerly known as "Chiron IL-2 Technology (Bermuda) Ltd.", name changed effective 12/6/01)1                  |                     | Bermuda                                                                                                                        
|Chiron U.K. Ltd. (in liquidation)                                                                                                |                     | United Kingdom                                                                                                                 
|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)
|                                                                                                                                 |                     |                                                                                                                                
|                                                                                                                                 |                     |                                                                                                                                
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|                                                                                                                                 |                     |                                                                                                                                
|                                                                                                                                 |                     |                                                                                                                                

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|                            |  |          | Chiron Canada ULC/Chiron Canada SRI (name changed from"PathoGenesis Canada, Ltd." 1/19/01; effective 12/13/01, amalgamated to Nova Scotia; effective 1/1/02, now a ULC under the name of
"Chiron Canada ULC"; effective 5/22/02, amended articles to also provide for a French name of "Chiron Canada SRI"; either name may be used interchangeably] |                                                                                                                                                                                            | Canada                                        
|--------------------------- |  | -------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | ----------------------------------------------
|                            |  |          | Chiron Italia S.r.l                                                                                                                                                                                                                                                                                                                                  |                                                                                                                                                                                            | Italy                                         
|                            |  |          | Chiron France S.a.r.l.                                                                                                                                                                                                                                                                                                                               |                                                                                                                                                                                            | France                                        
|                            |  |          | Chiron Blood Testing S.a.r.l.                                                                                                                                                                                                                                                                                                                        |                                                                                                                                                                                            | France                                        
|                            |  |          | Chiron Limited                                                                                                                                                                                                                                                                                                                                       |                                                                                                                                                                                            | Hong Kong                                     
|                            |  |          | Chiron Healthcare Ireland Limited dba "Chiron Ireland" (formerly known as "Chiron Blood Testing Distributor Limited")                                                                                                                                                                                                                                |                                                                                                                                                                                            | Ireland                                       
|                            |  |          |                                                                                                                                                                                                                                                                                                                                                      | Chiron Blood Testing Pty Ltd                                                                                                                                                               |                                               
|                            |  |          | Appold Consultadoria E Serviços Lda                                                                                                                                                                                                                                                                                                                  |                                                                                                                                                                                            | Portugal                                      
|                            |  |          |                                                                                                                                                                                                                                                                                                                                                      | Chiron Holding LLC (Formerly known as "Chiron LLC")                                                                                                                                        |                                               
|                            |  |          |                                                                                                                                                                                                                                                                                                                                                      | Chiron Holding LLC (Merged with and into "Chiron LLC" under the name of "Chiron Holding LLC")                                                                                              |                                               
|                            |  |          |                                                                                                                                                                                                                                                                                                                                                      | Chiron Hungary Üzleti Szolgáltató Hungary Korlátolt Felelösségû Társaság (aka Chiron Hungary Kft.) or Chiron Hungary Business
Services Limited Liability Company (aka Chiron Hungary Ltd)2 |                                               
|                            |  |          |                                                                                                                                                                                                                                                                                                                                                      | Ami' Centro Srl (formerly known as "Chiron Vaccines Srl")3                                                                                                                                 |                                               
|                            |  |          |                                                                                                                                                                                                                                                                                                                                                      |                                                                                                                                                                                            | Chiron Srl (formerly known as "Chiron S.p.A.")
|                            |  |          |                                                                                                                                                                                                                                                                                                                                                      |                                                                                                                                                                                            |                                               
|                            |  |          |                                                                                                                                                                                                                                                                                                                                                      |                                                                                                                                                                                            |                                               
|                            |  |          |                                                                                                                                                                                                                                                                                                                                                      |                                                                                                                                                                                            | Chiron Corp. s.r.o.                           
|                            |  |          |                                                                                                                                                                                                                                                                                                                                                      |                                                                                                                                                                                            | Chiron Redevelopment Corp. & Co. KG           
|                            |  |          |                                                                                                                                                                                                                                                                                                                                                      |                                                                                                                                                                                            |                                               
|                            |  |          |                                                                                                                                                                                                                                                                                                                                                      |                                                                                                                                                                                            |                                               
|                            |  |          |                                                                                                                                                                                                                                                                                                                                                      |                                                                                                                                                                                            |                                               
|                            |  |          |                                                                                                                                                                                                                                                                                                                                                      | Chiron Investment Company Spain, S.L. (ETVE)                                                                                                                                               |                                               
|Chiron Iberia S.L.          |  | Spain   
|Matrix Pharmaceutical, Inc. |  | Delaware

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