Conversion of unlisted shares series K into series A

Vaisala Corporation            Stock Exchange Release            December 22, 2010 at 12.00 Vaisala Oyj's 4000 unlisted shares (series K) have been converted into listed shares (series A). The conversion has been registered in the Finnish Trade Register December 22, 2010. Listing of the new series A shares has been applied for as of December 23, 2010. Further information: Jouni Lintunen, CFO, +358 40 5790181 Vaisala Corporation Distribution: NASDAQ OMX  Helsinki Oyj This announcement is distributed by Thomson Reuters on behalf of Thomson Reuters clients. The owner of this announcement warrants that: (i) the releases contained herein are protected by copyright and other applicable laws; and (ii) they are solely responsible for the content, accuracy and originality of the information contained therein. Source: Vaisala Oyj via Thomson Reuters ONE [HUG#1474182]