Vaisala - Company Announcement

Vaisala Corporation Commences Acquisition of Own Shares

Vaisala Corporation Stock Exchange Release 3 May 2012 at 2:20 pm.


The Board of Directors of Vaisala Corporation has decided to use the
authorization granted by the Annual General Meeting of Shareholders held on 28
March 2012 for acquiring the Company's own series A shares. A maximum total of
150,000 series A shares representing approximately 0.82% of the Company's total
shares, 1.01% of all series A shares and 0.22% of the total voting rights will
be repurchased. Currently the Company has 9,150 treasure shares in its
possession.

The shares will be acquired through public trading at the market price
prevailing at the time of acquisition in accordance with the rules of the NASDAQ
OMX Helsinki Ltd. The repurchase of own shares will begin on 10 May 2012 at the
earliest and the treasury shares to be repurchased will be primarily used in
Vaisala Groups's share-based incentive program to be implemented in 2012.

Vantaa, 3 May 2012

Vaisala Corporation

The Board of Directors

Further information
Kjell Forsén, President and CEO, Tel. +358 400 757 948


About Vaisala
Vaisala is a global leader in environmental and industrial measurement. Building
on 75 years of experience, Vaisala contributes to a better quality of life by
providing a comprehensive range of innovative observation and measurement
products and services for chosen weather-related and industrial markets.
Headquartered in Finland, Vaisala employs approximately 1400 professionals
worldwide and is listed on the NASDAQ OMX Helsinki stock exchange.
www.vaisala.com

Distribution
NASDAQ OMX Helsinki Ltd.
Major media
www.vaisala.com 

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