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

International reinsurance companies – Ad hoc arbitration proceedings
We successfully represented a panel of reinsurance companies in an international ad hoc arbitration. The dispute arose out of a reinsurance treaty under the terms of which the reinsurers had reinsured a portfolio of risks underwritten by the cedent. The parties disagreed as to whether the reinsurance provided coverage for a certain loss that had occurred because of the market turmoil caused by the Covid-19 pandemic. The case involved highly complex legal and contractual questions requiring special expertise on reinsurance law and practice. The arbitral tribunal rejected the counterparty’s claims for reinsurance compensation against our clients in full. The amount in dispute was approximately EUR 34 million.
Case published 16.9.2025
byFounders.vc – DataCrunch’s USD 64 million Series A funding round
We supported byFounders.vc as the Finnish counsel in their investment in DataCrunch Oy in a USD 64 million Series A funding round. DataCrunch provides scalable AI compute solutions from energy-efficient data centers in Iceland and Finland. byFounders.vc is the community-powered early-stage venture fund investing in globally ambitious teams connected to the Nordic and Baltic countries.
Case published 11.9.2025
Springvest – ReOrbit’s EUR 45 million Series A funding round
We advised Springvest Oyj in organising a EUR 45 million Series A funding round for ReOrbit, a space technology company and a leading provider of software-first satellites. It’s the largest all-equity Series A round in Finland and one of the most significant deals overall in the European space and defence sector. The purpose of the funding round is to support ReOrbit’s growth. The round consisted of a private placement reserved for professional and institutional investors, which included, e.g. Icebreaker.vc, Expansion VC, 10xFounders, Inventure VC, Varma Mutual Pension Insurance Company, and Elo Mutual Pension Insurance Company, and an EUR 8 million public share offering, which was oversubscribed within 4.5 hours. Springvest is a Finland-based investment firm that connects unlisted growth companies with investors. ReOrbit builds sovereign satellites and connected systems for national security.
Case published 9.9.2025
Ten Eleven Ventures & Tesi – EUR 275 million Series B financing round of IQM Quantum Computers
Castrén & Snellman advised the lead investors Ten Eleven Ventures and Tesi in the EUR 275 million Series B financing round of IQM Quantum Computers, the global leader in building quantum computers. The round is largest Series B round ever in Finland and the second largest in the Nordics. In addition to the lead investors represented by C&S, the round was participated by several new and existing investors, including pension funds Elo Mutual Pension Insurance and Varma Mutual Pension Insurance, strategic investors Companies of Schwarz Group and Winbond Electronics Corporation, and sovereign wealth funds EIC and Bayern Kapital. Ten Eleven Ventures is the original cybersecurity-focused, global, and stage-agnostic investment firm. The firm identifies, invests in, and helps grow top cybersecurity companies addressing critical digital security needs, leveraging its team, network, and experience to build successful businesses. Since its founding, Ten Eleven Ventures has raised over USD 1 billion and made over 60 cybersecurity investments across various stages worldwide. Tesi (Suomen Teollisuussijoitus Oy / Finnish Industry Investment Ltd) is a state-owned investment company with an industrial policy mission focused on driving economic growth, renewal, and investments. Tesi invests on market terms both in venture capital and private equity funds, and directly in startups, scale-ups, and large industrial projects. IQM Quantum Computers, founded as a deep tech spin-off from Aalto University in 2019, specialises in developing quantum computers utilizing superconducting circuits. The company designs and produces quantum processors at its facility in Espoo, providing computing solutions and optimizations tailored to both research and industrial applications. In addition to its Finnish operations, IQM has expanded its presence to Germany, France, Italy, Japan, Poland, Spain, Singapore, South Korea, and the United States.
Case published 4.9.2025
Vapaus Group – Acquisition of Azfalte
We represented Vapaus Group, a leading provider of employee bicycle benefit services, in its cross-border acquisition of Azfalte, a French corporate bicycle solutions company. The acquisition accelerates Vapaus Group’s international expansion and strengthens its position in sustainable mobility by combining Vapaus’s digital platform and circular-economy capabilities with Azfalte’s established enterprise programs and partner network in France. The transaction advances Vapaus’s growth strategy and increases its ability to help employers meet well-being and sustainability goals in one of Europe’s most dynamic cycling markets. Vapaus Group is at the forefront of sustainable mobility services and has been a pioneer in the employee bicycle benefit sector since 2020 with a vision to become the leading bicycle benefit service in Europe. Vapaus has automated the employee bicycle process through its technology platform, covering payroll, invoicing, logistics, insurance, and financing. Azfalte, founded in 2020, is a pioneer of corporate cycling in France, optimizing financing, tailored bikes, insurance, maintenance, assistance, training, and carbon tracking for the benefit of its clients.
Case published 1.9.2025
Wise Group – Sale of Wise People Group
We advised Wise Group AB (publ) in its sale of all shares in Wise Group’s Finnish subsidiary Wise People Group Oy (“WPG”) to Tetos Oy. The sale involves the divestment of Wise Group’s Finnish operations, and the purpose for the transaction is Wise Group’s ongoing streamlining of its operations, with a focus on the Swedish market. Wise Group’s companies specialise in recruitment, consultant hiring, HR consulting and leadership development. Wise Group is listed on Nasdaq Stockholm’s Small Cap list, with offices in Stockholm, Gothenburg, Malmö and Helsinki.
Case published 1.9.2025
OP Finland Infrastructure Fund – Conversion of convertible bond and additional investment in Lounea
We acted as legal advisor to OP Finland Infrastructure LP in connection with the conversion of the fund’s agreed EUR 50 million convertible bond into shares in Lounea Net Oyj in 2023. In connection with the conversion, the fund made a new additional investment of EUR 10 million in Lounea. As a result of the arrangement, OP Suomi Infra became a significant owner of Lounea Net Oyj with a 29% stake. Lounea is a Finnish optical fibre operator whose business consists of telecommunications infrastructure and ICT solutions. OP Finland Infrastructure is a fund investing in Finnish infrastructure. The fund is managed by OP Financial Group.
Case published 29.8.2025
Merger of Oomi and Lumme Energia
We are acting as the joint legal advisor to Oomi Oy and Lumme Energia Oy in a transaction whereby Lumme Energia will merge with Oomi. As from the completion of the merger, the combined entity will be the largest electricity retail and service company in the Finnish market. In 2024, Oomi reported a turnover of EUR 373.9 million and had approximately 110 employees. Lumme Energia’s turnover for the same year was approximately EUR 314.6 million and it had approximately 50 employees. The transaction is primarily driven by the recent developments in the electricity market and the strategic goal to develop competitive products and services. Another key objective is to further enhance the customer experience, which is a shared value between the two companies. As a result of the merger, Lumme Energia’s customers will transfer to Oomi, and Lumme Energia will become one of Oomi’s shareholders. The completion of the transaction is subject to an approval by the Finnish Competition and Consumer Authority.
Case published 29.8.2025

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