Ahlstrom Corporation STOCK EXCHANGE ANNOUNCEMENT 23 February 2010 Date: 23 February 2010 Exchange transaction: Buy Share class: AHL1V Amount: 3500 Average price /share: 11.48570 EUR Highest price /share: 11.50000 EUR Lowest price /share: 11.45000 EUR Total price: 40199,95 EUR The shares held by Ahlstrom Corporation on 23 February 2010 AHL1V 31157 AHLSTROM CORPORATION On behalf of Ahlstrom Corporation Pasi Väisänen EVLI BANK PLC