VAISALA CORPORATION STOCK EXCHANGE ANNOUNCEMENT 11.5.2015 SHARE REPURCHASE 11.5.2015 In the Helsinki Stock Exchange Trade date 11.5.2015 Bourse trade BUY Share VAIAS Amount 200 shares Total cost 4 789,46 EUR Average price/ share 23,9473 EUR Highest price/ share 23,99 EUR Lowest price/ share 23,80 EUR Vaisala Corporation now holds a total of 44 524 shares including the shares repurchased on 11.5.2015. On behalf of Vaisala Corporation NORDEA BANK FINLAND PLC Janne Sarvikivi Julius Summanen [HUG#1920654]