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                                                                     EXHIBIT 11

                                  Proteon, Inc.
                    Computation of Primary and Fully Diluted
                                 Loss Per Share
                      (in thousands except per share data)





                                               Three months ended                 Nine months ended
                                          September 27,   September 28,      September 27,   September 28,
                                              1997            1996               1997            1996
                                          ------------    ------------       -------------   -------------
                                                                                     

Net Loss                                    $(2,894)         $(1,763)            $(4,340)        $(3,967)                  
                                            =======          =======             =======         =======
                                                                      
Weighted average number of common                                     
  shares outstanding                         15,276           15,521              15,312          15,499  
                                                                      
Weighted average number of                                            
  common equivalent shares                       --               --                  --              --
                                            -------          -------             -------         ------- 
                                                                      
Weighted average number of common and                                 
  common equivalent shares outstanding                                
  used to calculate per share data           15,276           15,521              15,312          15,499 
                                            =======          =======             =======         =======
                                                                     
                                                                      
Net (loss) per share:                                                 
                                                                      
       Primary                              $ (0.19)         $ (0.11)            $ (0.28)        $ (0.26) 
                                            =======          =======             =======         =======
                                                                     
       Fully diluted                        $ (0.19)         $ (0.11)            $ (0.28)        $ (0.26)
                                            =======          =======             =======         =======