Disclosure of shareholdings

Pursuant to article 20 BEHG BB BIOTECH AG, Vordergasse 3, 8200 Schaffhausen and its wholly-owned subsidiary Biotech Target N.V., Snipweg 26, Curaçao, Netherlands Antilles hereby report that they increased their voting rights to more than 25% of the proportion of voting rights of BB BIOTECH AG as at September 25, 2008. Please find enclosed further details.