Fiiu Linninen

Senior Associate, Member of the Finnish Bar, Bachelor of Business Administration

Services

  1. Environment, Energy & Green Transition

Contact details

I advise clients on a wide range of legal issues related to the environment, natural resources and infrastructure in matters such as project planning and development, authority negotiations and procedures, administrative proceedings, business transactions and financial arrangements. My core expertise includes matters related to environmental and other permits, EIA processes, land use, environmental liability and nature conservation.

Prior to joining Castrén & Snellman, I worked at another business law firm, advising clients operating in sectors such as mining, forestry and energy. My clients include, for example, companies engaged in exploration and mining, ports and terminal operators, bioproduct plants, wind and solar power plants, and waste treatment and incineration plants.

I graduated from the University of Helsinki in 2020 with a Master of Laws degree. I also hold degree in business administration from a university of applied sciences, which has equipped me with an even better understanding of our clients’ business and needs.

Latest references

Nscale – Data centre project
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
Terrafame – Environmental and water management permit processes concerning the company’s entire operations and the KL1 side rock area
Castrén & Snellman successfully assisted Terrafame Ltd in environmental and water management permit processes concerning the company’s entire operations and the KL1 side rock area, on which the Supreme Administrative Court issued its decision on 12 February 2026 (KHO 366/2026 and 367/2026). The changes made to the decisions of the Vaasa Administrative Court as a result of Terrafame’s appeals, enable the company to implement its new strategy and develop its operations as planned. The decisions of the Supreme Administrative Court brought the nearly ten-year-long permit process to a close.
Case published 20.2.2026
Brookfield – EUR 1 billion holdco financing for DayOne Data Centers
We advised a leading global investment firm Brookfield, alongside a global sovereign wealth investor, on the Finnish law aspects of a EUR 1 billion holdco financing for DayOne Data Centers, a Singapore-headquartered developer and operator of hyperscale data centres. Structured as a seven-year secured holdco financing facility of €500 million, expandable to €1 billion – and secured by DayOne’s Finland platform – the financing will support the rollout of hyperscale developments in Lahti and Kouvola, providing nearly 300MW of planned capacity across Finland. The proceeds will also support DayOne’s global expansion across the EU and APAC, with flexibility to allocate to other key growth markets as required.
Case published 29.1.2026
Shareholders – Sale of the Suomen Autohuolto Group
We advised the shareholders of Suomen Autohuolto Oy in connection with the sale of the company’s entire share capital, to SAKA Finland Group Oy. Suomen Autohuolto Group is one of Finland’s largest companies specializing in brand-specific automotive maintenance and has locations in Oulu, Tampere, and from July, also in Järvenpää. The transaction is subject to final approval by the Finnish Competition and Consumer Authority (KKV).
Case published 26.6.2026
AI training
Natural Resources Institute Finland – AI training
We delivered two tailor-made AI workshops for the lawyers at the Natural Resources Institute Finland (Luke). We discussed the AI revolution and its impact on lawyers’ ways of thinking and working, and left the participants with practical solutions for enhancing and streamlining their work with Legora. Our AI-specialist lawyers prepared use cases tailored to Luke and the needs of public administration, which Luke received for its own use following the workshops. These use cases covered topics such as: utilising legal sources and the organisation’s own data to maximise AI results building and leveraging AI workflows AI-enhanced contract drafting based on a large volume of documents. The workshops sparked wide-ranging discussion on the role and benefits of AI in legal work. Participants appreciated how clearly and comprehensively our experts were able to present the nature and benefits of AI specifically within a legal context. ‘The workshops provided excellent support for Luke’s goal of leveraging AI responsibly and gave us concrete and ready-to-use practical takeaways,’ says Hannu Laitinen, Luke’s Senior Vice President, Administrative Affairs.
Case published 26.6.2026
Finnish Construction Management Consultancy — District Court Dismisses charge in occupational safety offence case concerning a safety coordinator
We successfully represented a Finnish construction management consultancy and a safety coordinator employed by the company in criminal proceedings concerning an alleged occupational safety and health offence. The prosecutor sought a penalty for an alleged breach of occupational safety regulations. The charge arose from a fall accident at a construction site where our client acted as the safety coordinator appointed by the developer. We assessed the scope of the safety coordinator’s duties in relation to the responsibilities of the main contractor, as well as how our client had fulfilled their obligations in practice. We demonstrated that our client had acted with due care and in full compliance with their duties throughout the planning, preparation and execution of the construction project. The District Court of Eastern Uusimaa dismissed the charge against our client. The Court held that our client, in their capacity as safety coordinator, had duly fulfilled the occupational safety obligations incumbent on the developer during the planning and preparation phases of the construction project and had not been aware of the fall protection deficiency identified at the site. The judgment is final insofar as our client is concerned.
Case published 22.6.2026
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

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