Leo Hynninen

Associate, Master of Laws

I advise our clients on domestic and cross-border mergers and acquisitions.

I joined Castrén & Snellman as an associate in May 2025. Before graduating, I worked as a trainee at two other law firms.

I hold a Master of Laws degree from the University of Helsinki.

Latest references

We acted as Finnish counsel to Scanreco in its acquisition of CrossControl. Mannheimer Swartling (Sweden) acted as lead counsel for Scanreco. CrossControl, founded in Sweden, is a high-tech supplier of advanced display computers and central vehicle computing solutions for industrial vehicles and machines. Scanreco is a world leading supplier of professional radio remote control systems to international machinery, heavy equipment, and crane manufacturers. The combined group comprises approximately 600 employees and generates annual revenue of around SEK 1.4 billion.
Case published 5.5.2026
We advised General Catalyst as lead investor on ICEYE’s EUR 150 million series E funding round, valuing the company at EUR 2.4 billion. ICEYE is the world leader in synthetic aperture radar (SAR) satellite systems and operates the largest SAR constellation globally. Its technology delivers objective, near real-time Earth observation in any weather or light conditions, enabling governments and institutions to manage risks and respond faster. General Catalyst is a global investment and transformation company, partnering with leading entrepreneurs to build toward global resiliency and applied AI. Its portfolio includes companies such as Airbnb, Snap, Stripe, Mistral AI, Hubspot, Anduril, Helsing and Legora. We advised General Catalyst on this transaction in collaboration with the US law firm Goodwin. 
Case published 8.12.2025
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
We acted as legal adviser to Banyan Software on its acquisition of Carus Ferry, a Finland-based provider of reservation, check-in and port operations software for ferry and passenger shipping operators. The acquisition further strengthens Banyan Software’s presence in the Nordic region while providing Carus with a long-term partner to support its continued growth and development. Carus was founded in 1998 and is headquartered in Mariehamn on the Åland Islands, Finland. The company develops mission-critical software for ferry, cruise and passenger shipping operators, covering the full passenger journey from booking and ticketing to capacity management, check-in and boarding. Carus also provides port automation, onboard sales systems and business information tools. The company serves approximately 30 operators across four continents and is the largest vendor by customer count in ferry reservation and departure control. Banyan Software is an acquirer and long-term operator of mission-critical software businesses serving specialised industries. Founded in 2016, Banyan follows a buy-and-hold-for-life approach and supports the long-term growth and development of its portfolio companies. Banyan operates more than 130 portfolio companies across North and South America, the United Kingdom, Europe and APAC. Following the acquisition of Carus, Banyan operates three businesses in the Nordic region.
Case published 20.10.2026
We advised Move Energy as an investor in connection with the combination of 3North Partners Plc and Steady Energy Oy and the related private placement and initial public offering of the combined company on Nasdaq First North Growth Market Finland. In connection with the transaction, 3North Partners received approximately EUR 69.8 million in investor commitments from a group of institutional and other investors, including Move Energy, to fund the combined company. Steady Energy is a Finnish nuclear technology company developing a new generation of small modular reactors (SMRs) particularly suited for district heating. Its LDR-50 reactor is designed to provide cities and utilities with a scalable and low-carbon alternative to combustion-based heat production.
Case published 19.10.2026
We advised Efima Oyj on the sale of its AI business to Better Care Technologies Oy. The transaction included Efima’s Moiva AI platform developed for the care sector, the related technology and brand, customer contracts, and the experts working in the business. 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 21.9.2026
We advised Neoen Renewables Finland Oy, part of the French Neoen Group, in its sale of a data centre project to a consortium consisting of international data centre developers and operators. This marked Neoen’s first data centre development project in Finland. Founded in 2008, Neoen is one of the world’s leading independent renewable energy producers. The company operates in 15 countries. It develops, finances, builds, owns, and operates solar power plants, wind farms, and battery storage systems. Neoen Group is owned by global alternative asset manager Brookfield Corporation.
Case published 17.9.2026
We advised Jolt Capital and Tesi in connection with their investment in VEV, a leading provider of commercial fleet electrification solutions. The investment, led by Jolt Capital with Tesi as co-investor, will support VEV’s next phase of growth and expansion across Europe. As part of the transaction, VEV became an independent company following the acquisition of Vitol’s stake in the business. Founded by Vitol, VEV provides integrated fleet electrification solutions combining fleet strategy, charging infrastructure, energy supply and operational services. Through its VEV IQ platform, the company supports more than 6,000 commercial electric vehicles across Europe and has been deployed across more than 600 sites spanning the transport, logistics and waste sectors. Jolt Capital is a private equity firm focused on growth investments in European deeptech companies. Tesi is a Finnish state-owned investment company that promotes Finnish business and economic growth through investments. We advised Jolt Capital and Tesi on the equity financing and structuring aspects of the transaction. International law firm Goodwin advised the investors on the acquisition of VEV.
Case published 10.9.2026

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