STONESOFT CORPORATION: NOTIFICATION PURSUANT TO CHAPTER 2, SECTION 10 OF THE FINNISH SECURITIES MARKET ACT

Stonesoft Corporation Stock Exchange Release 17 March 2010 at 10.30 am

STONESOFT CORPORATION: NOTIFICATION PURSUANT TO CHAPTER 2, SECTION 10 OF THE
FINNISH SECURITIES MARKET ACT

Stonesoft Corporation has received the following notification on 17 March 2010:

NOTIFICATION OF A CHANGE IN SHAREHOLDING PURSUANT TO CHAPTER 2, SECTION 9 OF THE
FINNISH SECURITIES MARKET ACT


1. Issuer of the shares

Stonesoft Corporation, business identity code 0837548-0.

2. Name of the shareholder subject to notification obligation

Shareholder Mr. Ilkka Hiidenheimo.

3. Reason for the notification

Decision made by the Board of Directors of Stonesoft Corporation on 17 March
2010 to start preparing a directed share issue, and the underwriting undertaking
related to it provided by Ilkka Hiidenheimo and announced on the same date.
According to the undertaking the company's Board of Directors may decide to
direct the shares possibly not subscribed for to the underwriter for
subscription.

4. Flagging threshold that is exceeded if the directed share issue and
underwriting undertaking are carried out in full

Hiidenheimo's  share of the total number of shares and voting rights exceeds 20
per cent (2/10).

5. Hiidenheimo's present shareholding

+------------+----------------+--------------+-------------------+-------------+
|ISIN code   |Number of shares|% of total    |Number of voting   |% of total   |
|            |                |number of     |rights             |number of    |
|            |                |shares        |                   |voting rights|
+------------+----------------+--------------+-------------------+-------------+
|FI0009801302|10 417 400      |18,18 %       |10 417 400         |18,18 %      |
+------------+----------------+--------------+-------------------+-------------+

The percentages have been calculated in proportion to the total number of shares
registered with the Trade Register and the total number of voting rights related
to them, i.e. 57,302,732 shares and voting rights.


6. Hiidenheimo's   total   shareholding   if   the   directed  share  issue  and
Hiidenheimo's underwriting undertaking are carried out in full

+----------------+-------------------+----------------------+------------------+
|Number of shares|%  of  total number|Number    of    voting|%  of total number|
|                |of shares          |rights                |of voting rights  |
+----------------+-------------------+----------------------+------------------+
|15 737 210      |24,98              |15 737 210            |24,98             |
+----------------+-------------------+----------------------+------------------+

The  percentages have been calculated in proportion  to the number of shares and
voting rights that the company will have outstanding if the directed share issue
is carried out in full, i.e. 63,002,732 shares and voting rights.


Helsinki, 17 March 2010

ILKKA HIIDENHEIMO


For further information, please contact:
Ilkka Hiidenheimo, CEO, Stonesoft Corporation
Tel. +358 9 476 711
E-mail: ilkka.hiidenheimo@stonesoft.com


Distribution:
NASDAQ OMX Helsinki Ltd
Main media
www.stonesoft.com




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