Iris Brisson

Senior Associate, Member of the Finnish Bar

I advise our clients in assignments relating to dispute resolution. My main areas of practice are domestic and international court and arbitration proceedings.

Prior to joining Castrén & Snellman, I worked as an associate with the dispute resolution team of another Finnish law firm and as an in-house lawyer for a global company manufacturing mobile phones. During my studies, I gained valuable work experience by working as a trainee at reputable Finnish law firms and by completing an internship with one of the case management teams of the ICC International Court of Arbitration in Paris.

I hold a Master of Laws degree from the University of Helsinki.

Latest references

We successfully represented VR Group before the Supreme Court in a case concerning the meal break practice of commuter train drivers. On 6 February 2026, the Supreme Court ruled in VR’s favour (decision KKO:2026:12), confirming that VR had the right to amend the commuter train drivers’ meal break practice in 2021 by rendering the break unpaid in accordance with the applicable collective agreement. This decision clarifies the interpretation of collective agreements and employment legislation as well as the limits of the employer’s right to direct work. Over 250 commuter train drivers challenged the unpaid meal break practice which VR introduced in April 2021. Before the change, meal breaks had a long history of being paid. The change was based on the train drivers’ collective agreement, which allows for meal breaks to be organised either as paid or unpaid time. The Supreme Court ruled that the scheduling and managing of breaks falls within the core area of the employer’s right to direct work. This increases the threshold for an established practice becoming a binding condition for the parties. Merely following a practice consistently and over a long period of time does not make the practice binding; instead, the employer’s intent to commit to the practice must be clearly evident from the employer’s conduct or other circumstances. As both alternatives – paid and unpaid – for organising meal breaks had been retained in the collective agreement despite other amendments over the years, it could not be considered that VR had intended to commit to the paid break practice and waive its right to direct work as regards break scheduling. It was also significant that the employment contracts explicitly referred only to the collective agreement as regards working time. The Supreme Court deemed that the employees’ paid meal break was not an established term of employment and that VR was entitled to change the practice based on the collective agreement. The employer had the right, by virtue of its right to direct work, to unilaterally change the meal break practice by choosing to apply the other arrangement permitted by the collective agreement.
Case published 3.3.2026
We represent a major energy company in arbitration. The dispute has arisen out of a long-term energy supply agreement and the value of the claims is approximately EUR 33 million.
Case published 19.9.2023
We advised Excelerate Energy on the conclusion of a lease agreement with Gasgrid Finland Oy for the Floating Storage and Regasification Unit (FSRU) Exemplar. The Inkoo LNG terminal project will have a significant impact on securing the supply of gas to Finland and Estonia as imports of pipeline gas from Russia cease. The Exemplar is the first FSRU in Finland and the Inkoo LNG terminal project is legally unique. Moreover, the project, which is critical for Finland’s and the Baltics’ gas supply, was completed in an exceptionally short timeframe. Our experts assisted the company in a wide range of areas including contracts, energy legislation, licensing, labour law, taxation and structuring.
Case published 9.6.2023
We advised the NATO Innovation Fund as lead investor on Kelluu’s EUR 15 million Series A funding round, with participation from Keen Venture Partners, Gungnir Capital, and Tesi. Kelluu is a Finnish deep tech company operating the world’s largest autonomous airship fleet. We advised NIF on this transaction alongside global law firm Latham & Watkins.
Case published 17.4.2026
Castrén & Snellman advised Nscale, a European AI infrastructure company, in connection with its planned data centre project in Harjavalta, Finland. The facility will be located in the Sievari industrial area. Castrén & Snellman’s advisory role encompassed the negotiation and execution of a site securing and development agreement (SSDA) with Fortum, as well as the preliminary land sale process for the Sievari site with the Town of Harjavalta. Under the SSDA, Fortum supports the advancement of Nscale’s project development, including grid connection design and permitting.
Case published 15.4.2026
We are acting as legal adviser to Taaleri Plc on its acquisition of a 51 per cent ownership stake in Nordic Science Investments Oy (NSI), marking Taaleri’s expansion into deeptech-driven venture capital. Through the transaction, Taaleri broadens its private equity offering into early-stage venture capital funds as well as the commercialisation and scaling of research-driven innovations. NSI is a Finnish venture capital fund manager operating across the Nordic and Baltic regions, focusing on early-stage investments in research- and science-based technologies. Its portfolio companies develop, among other things, health technologies, life sciences, advanced materials and AI-driven solutions. In addition to providing growth capital, NSI supports spin-out companies with strategic guidance, access to networks and assistance in building teams during the early phases of business development. NSI’s first fund, the EUR 45 million NSI Nordic Science I Ky, was established in 2024 and has to date invested in 22 early-stage companies in Finland, Sweden and the Baltic countries. Taaleri is a specialist in investments, private asset management and non-life insurance, with a strong position in renewable energy, bioindustry and housing investments as well as credit risk insurance. Taaleri has EUR 2.7 billion of assets under management in its private equity funds, co-investments and single-asset vehicles, employs approximately 130 people and is listed on Nasdaq Helsinki. The founders of NSI will continue in their operational roles following the transaction. The completion of the transaction is subject to approval by the FIN-FSA.
Case published 13.4.2026
We delivered two information design workshops for the legal department of the Finnish Centre for Pensions, with participants from both legal and other professional backgrounds. In the sessions, we applied the principles of legal design thinking to the Finnish Centre for Pensions’ field of operation and background materials, also utilising AI as a design tool. The participants found the tailored training highly useful and commended the trainers for their in-depth familiarisation with the Centre’s opinion drafting process and operating environment. As a result of the workshops, our experts proposed a new structural and linguistic model for the legal department of the Finnish Centre for Pensions for drafting opinions and guidelines. The proposal was well received as clear and applicable to the participants’ everyday work. In addition, we presented tailored AI use cases to support experts, allowing for a more efficient AI-assisted way of working. Our experts who delivered the workshops combined their legal expertise with their leading experience in legal design. The participants appreciated this versatile expertise, which enabled a knowledgeable, creative and applied approach to legal writing. ‘C&S created a well-structured training tailored to our needs, providing clear direction for our organisation and concrete takeaways for our experts in their day-to-day work,’ says Mari Kuunvalo, Head Of the Legal Department at the Finnish Centre for Pensions.
Case published 10.4.2026
We advised Aktia Bank Plc on the issuance of an EUR 80 million Additional Tier 1 (AT1) bond. The bond pays a fixed interest rate of 6.75 per cent semi-annually. The bond is perpetual, and Aktia has the right to redeem or repurchase it in accordance with the terms of the bond, subject to certain conditions. The bond was issued on 1 April 2026. In addition, we assisted Aktia in listing the bond on the Nasdaq Helsinki Ltd stock exchange. For the listing, we prepared Finland’s first EU Follow-on prospectus for a bond. The EU Follow-on prospectus was introduced on 5 March 2026 with an update to the Prospectus Regulation (EU) No. 2017/1129. The EU Follow-on prospectus is a new type of prospectus that can be used, among others, by issuers whose securities have been admitted to trading on a regulated market continuously for at least the 18 months preceding the offer to the public or the admission to trading on a regulated market of the new securities. A follow-on prospectus is simpler than a so-called traditional prospectus, and it is intended to avoid repeating information that the issuer has already disclosed. Nordea Bank Abp acts as the sole structuring advisor for the issue of the Notes. Nordea Bank Abp, Danske Bank A/S and ABN Amro Bank N.V. act as the lead managers for the issue of the Notes. 
Case published 7.4.2026

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