VAISALA CORPORATION STOCK EXCHANGE ANNOUNCEMENT 18.5.2015 SHARE REPURCHASE 18.5.2015 In the Helsinki Stock Exchange Trade date 18.5.2015 Bourse trade BUY Share VAIAS Amount 1 655 shares Total cost 39 726,95 EUR Average price/ share 24,0042 EUR Highest price/ share 24,04 EUR Lowest price/ share 23,90 EUR Vaisala Corporation now holds a total of 48 167 shares including the shares repurchased on 18.5.2015. On behalf of Vaisala Corporation NORDEA BANK FINLAND PLC Janne Sarvikivi Julius Summanen [HUG#1922244]