VAISALA CORPORATION STOCK EXCHANGE ANNOUNCEMENT 12.5.2015 SHARE REPURCHASE 12.5.2015 In the Helsinki Stock Exchange Trade date 12.5.2015 Bourse trade BUY Share VAIAS Amount 1 046 shares Total cost 25 507,76 EUR Average price/ share 24,3860 EUR Highest price/ share 24,39 EUR Lowest price/ share 24,30 EUR Vaisala Corporation now holds a total of 45 570 shares including the shares repurchased on 12.5.2015. On behalf of Vaisala Corporation NORDEA BANK FINLAND PLC Janne Sarvikivi Julius Summanen [HUG#1921143]