Rule 2.10 Announcement

19 August 2004

                                 Microgen plc                                  

                            Rule 2.10 announcement                             

In accordance with Rule 2.10 of the City Code on Takeovers and Mergers,
Microgen plc announces that, as at close of business on 18 August 2004, it has
in issue 91,235,040 ordinary shares of 5p each ('Microgen Shares').

The International Securities Identification Number for the Microgen Shares is
GB0005869531.