Onni Koivu

Senior Associate, Master of Laws

Services

  1. Dispute Resolution

Contact details

I specialise in dispute resolution. My areas of practice include both domestic and international court and arbitration proceedings.

I have assisted our clients in commercial disputes relating to, among others, industrial construction projects and copyrights. In addition, I have experience acting as counsel in investor-state arbitration.

I joined Castrén & Snellman’s Dispute Resolution service as a trainee already before my graduation.

I have a Master of Laws degree from the University of Turku. In addition, I have studied law at the University of Verona in Italy.

Latest references

Prisma Properties – Acquisition of a retail property
We advised Prisma Properties in a real estate transaction in which the company acquired a retail property in Helsinki from Hartela.  The acquired property was built specifically for the discount retailer Jula. Completed in October 2025, the property is modern and very energy-efficient, and it is fully leased to Jula under a 10-year lease agreement. The property located in the Konala district, adjacent to the busy Ristikko shopping centre, spans 2,600 square metres. Prisma Properties is a fast-growing developer and long-term owner of modern properties for discount retail, grocery retail, and quick-service restaurants. The company operates across the Nordics and manages a property portfolio valued at approximately EUR 650 million, primarily consisting of newly developed properties with long lease agreements.
Case published 29.10.2025
SRV – Sale of SRV Infra
We advised SRV Group Plc in its sale of SRV Infra Ltd to Kreate Ltd. The completion of the transaction is subject to regulatory approvals. The parties expect the transaction to be closed by the end of 2025. SRV, established in 1987, is a Finnish developer and innovator in the construction industry. The company is listed on the Helsinki Stock Exchange. In 2024, SRV’s revenue totalled EUR 745.8 million.
Case published 27.10.2025
Suomen Aurinkovoima – Financing arrangement to build solar parks
Castrén & Snellman acted as legal advisor to Suomen Aurinkovoima Oy and its owners in a financing tender process and a financing arrangement implemented with Danske Bank to secure financing for the company’s future solar park projects. Suomen Aurinkovoima, established by Oulun Seudun Sähkö, Oulun Energia, Vantaan Energia and Savon Voima, is a company focused on increasing domestic solar power. The company manages solar park projects from planning to implementation and maintenance, and its goal is to build dozens of new solar parks across Finland by 2030.
Case published 22.10.2025
DNB Bank ASA – Lease and development of premises
We advised DNB Bank ASA in its agreement with Fennia Mutual Insurance Company on the development and lease of the premises at Fabianinkatu 8, Helsinki. With the lease agreement, DNB Bank ASA will focus all its Finnish operations at the Fabian 8 office. The other tenants at the renewed premises will be DNB Carnegie Investment Bank AB’s Finnish operations and DNB Auto Finance Oy. In connection with the long-term lease agreement, the parties also agreed on a major renovation project to completely refurbish the premises. The object of lease will be completed in the second half of 2027.
Case published 10.10.2025
Yellow Film Studios – Merger of Yellow Film Studios and REinvent Studios
We advised Yellow Film Studios, the largest independent film and television production company in the Nordics, in its strategic merger with Danish film industry sales and financing studio REinvent Studios. Together they form Reinvent Yellow, a unified hub for television and film production, sales, financing and innovation, combining over three decades of production experience and a vast catalogue of titles.
Case published 8.10.2025
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

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