Iris Brisson

Senior Associate, Member of the Finnish Bar

Services

  1. Dispute Resolution

Contact details

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

VR – Supreme Court decision clarifies working time practices
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
Energy company – Dispute arising from an energy supply agreement
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
Excelerate Energy – Chartering an FSRU to Finland
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
Efima – Sale of financial management services business
We advised Efima Oyj on the sale of its financial management services business to Rantalainen as part of its strategic focus on fully concentrating on the delivery of business applications as well as data and AI solutions. As a result of the transaction, customer contracts related to financial management services and 65 experts working in these services will transfer to Rantalainen. The transaction will be carried out as a transfer of business, and the experts will move to the new owner as existing employees. Efima is a Finnish digital company that supports the sustainable growth of large and mid-sized companies by streamlining their business processes and by creating competitive advantage through the innovative use of artificial intelligence and data. The company has nearly 200 experts based in Helsinki and Tampere.
Case published 12.6.2026
Ugly Duckling Ventures – EUR 6.5 million funding round of Skyfora
We advised lead investor Ugly Duckling Ventures on the EUR 6.5 million funding round of Skyfora. The round also included Eviny Ventures, LUMO Labs and EIC Fund, alongside non-dilutive funding from Business Finland. The investment will support the commercial scale-up of Skyfora’s weather intelligence solutions, the expansion of partnerships with telecom operators, forecasting providers and meteorological institutions, and the continued growth of the team. Skyfora is a Finnish company developing high-resolution weather data solutions using patented technology that extracts atmospheric data from GNSS receivers embedded in existing infrastructure, such as telecom networks. By unlocking previously untapped data sources, Skyfora enables the next generation of AI-driven weather forecasting and supports improved decision-making across weather-sensitive industries. Ugly Duckling Ventures is a Copenhagen-based venture capital firm focused on early-stage Nordic B2B technology companies, with an emphasis on medtech, resilience tech and business services.
Case published 10.6.2026
castren snellman general atlantic iceye
General Atlantic – ICEYE’s EUR 1 Billion Series F Funding Round
We advised General Atlantic as the lead investor on ICEYE’s EUR 1 billion series F funding round, valuing the company at over EUR 10 billion. ICEYE raised EUR 450 million (USD 520 million) in a primary Series F funding round led by General Atlantic. Additional investors included Solidium, Tesi, Varma, Ilmarinen, Lifeline Ventures, Nokia, Qatar Investment Authority (QIA) and TCV. Together with a secondary placement, the total fundraising exceeds EUR 1 billion. ICEYE is the world leader in sovereign intelligence from space, providing continuous monitoring capabilities to detect and respond to changes in any location on Earth. The company operates the world’s largest and most advanced Synthetic Aperture Radar satellite constellation. General Atlantic is a leading global investor with more than four and a half decades of experience providing capital and strategic support for over 885 companies throughout its history. As of March 31, 2026, General Atlantic manages approximately USD 126 billion in assets across its investment strategies. We advised General Atlantic on this transaction in collaboration with the international law firm Paul, Weiss, Rifkind, Wharton & Garrison.
Case published 9.6.2026
Oomi Solar – Sale of a Solar Power Plant and Battery Energy Storage Project
We advised Oomi Solar Oy on the sale of a solar power park and battery energy storage project to Tuulipolar Oy. The transaction concerned a 24 MWp solar power plant and a 36 MW / 70 MWh battery energy storage system (BESS) to be constructed in Tornio. Tuulipolar Oy will act as the owner and operator of the plant, while Oomi Solar Oy will be responsible for its design and construction. The project will form the world’s northernmost industrial hybrid power plant, contributing to Finland’s green energy transition by increasing renewable energy production and electricity storage capacity in Northern Finland. The hybrid solution enables optimization of production as well as active participation in electricity markets and reserve services, improving the project’s profitability and supporting the balance of the electricity system year-round. Electricity production from the hybrid plant is expected to begin in 2028. Oomi Solar Oy is a Finnish renewable energy expert with experience from nearly 200 MW of installed solar capacity. The company helps businesses and communities accelerate the green transition by offering comprehensive solutions, including solar power plants, energy storage systems, and related lifecycle services from project development to maintenance. Oomi Solar Oy employs more than 20 energy professionals and delivers solar power projects across Finland. The company’s vision is to be Finland’s most desired partner for solar energy and energy solutions.
Case published 5.6.2026
United Bankers – Sale of three care properties
United Bankers – Sale of three care properties
We advised United Bankers on the sale of three care properties to Kinland AS. The buildings were completed between 2021 and 2022 and meet high technical and environmental standards. All three properties are fully leased. The portfolio has a weighted average unexpired lease term of 13 years.
Case published 1.6.2026

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