Trustee appointed for the arbitration proceedings concerning the redemption of minority shares in WithSecure Corporation

Diana BidCo Oy (“Diana BidCo”) has, by submitting an application to the Redemption Board of the Finland Chamber of Commerce dated 17 November 2025, commenced redemption proceedings in respect of WithSecure Corporation’s (“WithSecure”) minority shares by initiating arbitration proceedings in accordance with Chapter 18, Section 3 of the Finnish Companies Act in order to obtain ownership of all the issued and outstanding shares in WithSecure.

Due to Diana BidCo’s application for the above-mentioned arbitration proceedings, the Redemption Board of the Finland Chamber of Commerce has applied to the District Court of Helsinki for the appointment of a trustee to supervise the interests of WithSecure’s minority shareholders during the redemption process. The Redemption Board of the Finland Chamber of Commerce has notified Diana BidCo that the District Court of Helsinki has, with its decision given on 5 December 2025, appointed attorney-at-law, trained on the bench, Niina Rosenlund to act as such trustee.

Diana BidCo’s notice, as referred to in Chapter 18, Section 5, Subsection 2 of the Finnish Companies Act, is attached to this release as Appendix 1 and is available on the website of WithSecure at https://www.withsecure.com/en/about-us/investor-relations/recommended-cash-offer. It will also be published in the National Official Journal of Finland (Virallinen lehti in the Finnish language) without delay.

Investor and Media enquiries:

WithSecure

Tom Jansson
CFO
Tel. +358 9 2520 0700
investor-relations@withsecure.com

Distribution:
Nasdaq Helsinki Ltd
Principal media

ABOUT WITHSECURE

WithSecure, formerly F-Secure Business, is a European cyber security partner trusted by businesses and IT service providers worldwide, delivering outcome-based cyber security solutions that help businesses stay ahead of modern cyber threats. Boasting more than 35 years of industry experience, WithSecure has built its award-winning portfolio of Elements Cloud to navigate the paradigm shift from reactive to proactive cyber security and Cloud Protection for Salesforce to protect Salesforce users from malware and phishing threats. Committed to European digital sovereignty, WithSecure prioritizes European Way of data protection, privacy and regulatory compliance, which have become critical differentiators in the global cyber security market. In alignment with its commitment to collaborative growth, WithSecure empowers its customer and partner ecosystem through flexible commercial models, ensuring mutual success across the dynamic cyber security landscape. WithSecure was founded in 1988, and it is listed on the official list of Nasdaq Helsinki.