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 advise Korona Invest and the other shareholders of Innoflame Oy on the sale of Innoflame to Sponsor Capital. The transaction makes Sponsor Capital the new majority owner of Innoflame. Korona Invest has been a shareholder of Innoflame since 2021 and, together with the other selling shareholders, has over the past five years supported the company’s growth, development and several strategically significant corporate transactions, through which Innoflame has strengthened its position as Finland’s leading product media company. The ownership change is intended to support Innoflame’s next phase of growth, including its ambition to build a significant European product media company with the capability to expand rapidly into new markets. The transaction is conditional to the customary closing conditions such as authority approvals. Innoflame is one of Finland’s leading product media specialists, helping its clients build a unified brand experience by offering the design, sourcing and management of product media as a single integrated service. Korona Invest is a Finnish private equity firm founded in 2006, specialising in buyout and growth investments in domestic small and medium-sized enterprises. It makes both majority and minority investments, structuring each project to suit the company’s growth strategy. 
Case published 27.8.2026
We advised Hopeasalmen Telakka Oy, part of Marina Group, on the acquisitions of Iisiveneily and Porvoon Venekorjaamo. The transactions form part of Marina Group’s expansion into the Finnish marina and boatyard sector, strengthening its position under the Quattro Marine brand. Following the acquisitions, Quattro Marine’s Finnish operations comprise Hopeasalmen Telakka, which operates boatyard facilities in Helsinki’s Mustikkamaa and in Tolkkinen, Porvoo, together with Iisiveneily and Porvoon Venekorjaamo. Marina Group is a Norwegian marina and boatyard consortium owned by the private equity sponsor Norvestor. It has grown rapidly through acquisitions to become the Nordic region’s largest boating services provider, having acquired 24 marinas and boatyards across Norway, Sweden and Finland within roughly a year.
Case published 24.8.2026
We advised Neste as it signed a EUR 250 million 10-year loan with NIB. The loan will finance Neste’s investments related to research and development (R&D) in processing lower-quality feedstocks into high-quality renewable products; as well as the liquefied waste plastics (LWP) investment at Neste’s refinery in Porvoo, Finland. The R&D activities supported by the loan focus on the development of renewable solutions. These include, for example, expanding feedstock capabilities and technologies that enable the processing of new and lower-quality waste and residues into high-quality renewable end products. Part of the financing supports Neste’s liquefied waste plastics investment in Porvoo, related to upgrading low-quality plastic waste into high-quality feedstock at an industrial scale. The investment contributes to advancing circular economy solutions by enabling the use of hard-to-recycle plastic waste as a replacement for virgin fossil raw materials. The unit has an annual capacity to process up to 150,000 tonnes of liquefied waste plastic. Production ramp-up commenced in 2026.
Case published 19.8.2026
We advised Aspo Plc, ESL Shipping Ltd and AtoBatC Shipping AB in relation to finance matters in connection with the demerger of Aspo, by which all the shares in ESL Shipping Ltd held by Aspo, together with the related assets and liabilities, will be transferred to a new independent company to be named ESL Shipping Group Plc. Aspo intends to apply for the shares of ESL Shipping Group to be admitted to trading on the regulated market of Nasdaq Helsinki. It is further intended that Aspo be renamed Telko Group Plc. 
Case published 19.8.2026
We acted as Finnish law legal adviser to the lenders and the export credit agencies in connection with the EUR 514.4 million green project financing for the development and construction of Easpring Finland New Materials Oy’s cathode active material (CAM) manufacturing plant in Kotka, Finland. The borrower, Easpring Finland New Materials Oy, is a joint venture owned by Beijing Easpring Material Technology, Finnish Minerals Group and LG Energy Solution. The financing was provided by six international commercial banks, with Société Générale acting as financial adviser and mandated lead arranger together with Natixis as co-mandated lead arranger, and DNB, ICBC, ING and Standard Chartered participating as lenders, with support from the export credit agencies Finnvera and Sinosure. The project represents a significant milestone for Finland and the European battery value chain by strengthening Europe’s domestic supply of cathode active materials, a key component in lithium-ion batteries for electric vehicles and energy storage applications. Once the first phase of the project is operational, the Kotka facility is expected to produce approximately 60,000 tonnes of cathode active material annually, making it one of the largest CAM production plants in Europe and supplying leading battery manufacturers across Europe. 
Case published 21.7.2026

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