Ahlstrom: supplement to the merger prospectus

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Ahlstrom Corporation STOCK EXCHANGE RELEASE March 17, 2017 at 11:03

Ahlstrom: supplement to the merger prospectus

Munksjö Oyj ("Munksjö") has supplemented the merger prospectus dated December 16, 2016. The Finnish Financial Supervisory Authority has on March 17, 2017 approved the supplement to the merger prospectus, which relates to the approval of the merger by the European Commission, Munksjö`s resolution on a return of equity and Ahlstrom`s resolution on the payment of a dividend.

The Finnish language merger prospectus and the supplement to the Finnish language merger prospectus are available on the internet at www.ahlstrom.com/fi/Sijoittajat/ ahlstromin-ja-munksjon-yhdistyminen and www.munksjo.com/ahlstrommunksjo/fin as well as at the registered office of Ahlstrom at Alvar Aallon katu 3 C, FI-00100 Helsinki, Finland, and at the registered office of Munksjö at Eteläesplanadi 14, FI-00130 Helsinki, Finland. The English language merger prospectus and the supplement to the English language merger prospectus are available on the internet at www.ahlstrom.com/en/Investors/ahlstrommunksjo-combination/ and www.munksjo.com/ahlstrommunksjo.

Ahlstrom Corporation

Ahlstrom in brief
Ahlstrom provides innovative fiber-based materials with a function in everyday life. We are committed to growing and creating stakeholder value by proving the best performing sustainable fiber-based materials. Our products are used in everyday applications such as filters, medical fabrics, life science and diagnostics, wallcoverings, tapes, and food and beverage packaging. In 2016, Ahlstrom`s net sales amounted to EUR 1.1 billion. Our 3,200 employees serve customers in 22 countries. Ahlstrom`s share is quoted on the Nasdaq Helsinki. More information is available at www.ahlstrom.com.

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