Vaisala Oyj Stock Exchange Announcement 12.12.2008 at 11.00 Conversion of unlisted shares series K into series A Vaisala Oyj's 801 unlisted shares (series K) have been converted into listed shares (series A). The conversion has been registered in the Finnish Trade Register December 12, 2008. Listing of the new series A shares has been applied for as of December 15, 2008. Further information: Jouni Lintunen, CFO, tel +358 9 8949 2215 or +358 40 5790181 Vaisala Oyj Distribution: Helsinki Exchanges