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
Delta Capacity – Acquisition of BESS Project
We acted as Finnish legal advisor to Delta Capacity in connection with its acquisition of the ready-to-build Karppio battery energy storage system (BESS) project from Helios Nordic Energy. The acquisition was made and the project will be implemented together with Strioga Family Foundation. The Karppio BESS project is located in Teuva, Finland, and has a capacity of 125 MW / 300 MWh. Delta Capacity will lead the remaining development of the project through to commissioning, planned for 2027, and will serve as long-term asset manager. Delta Capacity is a Swiss-based developer of utility scale battery storage systems. The acquisition adds to Delta Capacity’s growing Nordic portfolio. 
Case published 20.7.2026
Swedbank – Refinancing of Trophi’s Finnish retail real estate portfolio
We advised Swedbank AB (publ) on the refinancing of a large Finnish retail real estate portfolio owned by Trophi’s Finnish subsidiaries. Trophi is the leading Nordic real estate company focusing on grocery anchored retail properties, with 278 properties across Sweden and Finland. Finland is a market that continues to develop and is also strategically important for Trophi, accounting for approximately 30% of Trophi’s letting and property value.
Case published 17.7.2026
HANZA – Acquisition of Fortaco Finland’s heavy mechanics and assembly business
We are acting as Finnish legal advisor to HANZA in connection with its acquisition of Fortaco Finland’s heavy mechanics and assembly business. The transaction is structured as a combined asset and share acquisition and includes Fortaco Finland’s heavy mechanics and assembly operations in Finland, as well as shares in two Estonian and two Polish subsidiaries. The transaction is expected to close during the fourth quarter of 2026, subject to customary closing conditions, including regulatory approvals. Founded in 2008, HANZA is a Swedish mechanical engineering and electronics contract manufacturing company listed on the Nasdaq Stockholm main list. HANZA has approximately 5,000 employees and annual sales of SEK 10 billion. We advise HANZA on this transaction in collaboration with the Swedish law firm Lindahl.
Case published 15.7.2026
RevolutionRace – Acquisition of ICANIWILL
We acted as Finnish counsel to RVRC Holding AB (RevolutionRace) in its acquisition of 90.1% of the shares in ICANIWILL AB (ICIW). Mannheimer Swartling (Sweden) acted as lead counsel for RevolutionRace. ICIW, founded in Sweden in 2012, is a Swedish training apparel brand.  RevolutionRace is a fast-growing Swedish outdoor brand offering multifunctional products to people with an active lifestyle. The company operates with a digital D2C business model reaching customers in approximately 40 countries. The company is listed on Nasdaq Stockholm since 2021. 
Case published 14.7.2026
Special investment fund managed by Mandatum – Sale of PMK Building
We advised a special investment fund managed by Mandatum on the sale of the PMK Building, a mixed-use commercial property located in Tammela, Tampere. The property hosts dozens of tenants and offers, inter alia, warehouse, production and office premises.
Case published 13.7.2026

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