Helmi Puustinen

Associate, Master of Laws

Services

  1. Private Equity
  2. Private M&A

Contact details

I advise both international and domestic clients on Private Equity and Venture Capital investments, covering the full spectrum of investments and M&A transactions for private equity firms and their portfolio companies across a variety of industries. Beyond investment-driven mandates, I also advise clients in broader Private M&A matters.

Before joining Castrén & Snellman, I gained experience on both sides of the table – within top Finnish law firms and the venture capital industry. Having worked as an investor in VC funds during my studies, I understand the entire investment lifecycle from early-stage startups to late-stage growth companies, with a specialized focus on the digital green transition.

This multidisciplinary background allows me to provide commercially minded, strategically aware advice that is always focused on what matters most to the client. I am particularly inspired by emerging technologies, which continue to shape the future.

I’m on secondment in Stockholm until August 2026.

Latest references

G&W Electric – Acquisition of Safegrid
We advised G&W Electric with its acquisition of Safegrid Oy, a leading provider of intelligent grid monitoring solutions based in Finland. The acquisition accelerates G&W Electric’s long-term strategy to integrate intelligent monitoring and predictive analytics into its power distribution portfolio, strengthening its offering to utility customers worldwide. Founded in 1905 and headquartered in Bolingbrook, Illinois, G&W Electric is a global leader in innovative power grid solutions, with a presence in over 100 countries. The company is known for advanced load and fault interrupting switches, reclosers, sensors, system protection equipment, power grid automation, intelligent grid monitoring, and transmission and distribution cable accessories. Safegrid is a Finnish technology company headquartered in Espoo, Finland. The company develops the Intelligent Grid System®, a grid monitoring solution that combines instant-on wireless sensors with advanced analytics to deliver real-time insight into grid conditions, enabling utilities to identify emerging issues, anticipate failures, and reduce outage duration across medium and high voltage distribution and transmission networks.
Case published 8.5.2026
CapMan Growth – Investment in Kuntokeskus Liikku
We are assisting CapMan Growth in its significant investment in Kuntokeskus Liikku, a Finnish gym chain known for its high-quality self-service facilities and excellent value for money. The investment will further strengthen Liikku’s position as a market leader and support the continued execution of its growth strategy. Liikku is one of Finland’s leading fitness chains, with more than 70 locations across the country serving nearly 90,000 members. The company’s concept is to offer high-quality self-service gyms at an exceptionally competitive price point which, combined with strong operational efficiency, provides a solid foundation for profitable growth. The company’s main shareholder is COR Group, a long-time partner of CapMan Growth, and a Finnish health and wellness conglomerate known for active ownership and long-term value creation. CapMan Growth is a leading Finnish growth investor that makes significant investments in entrepreneur-led growth companies with a turnover of €10–200 million. CapMan Growth is part of CapMan, which is a leading Nordic private equity investor engaged in active value creation work. CapMan has been listed on the Helsinki Stock Exchange since 2001.
Case published 27.2.2026
CapMan Growth – Investment in restaurant chain Factory
We are assisting CapMan Growth in making a significant investment in Factory, a Finnish restaurant chain known for its high-quality homemade meals and excellent value for money. The investment supports Factory’s ambitious growth strategy to expand nationwide and strengthen its presence also in shopping centres. Industry veteran Aku Vikström also joins as a co-investor and member of the board to support the company. Factory is a restaurant chain that specialises in high-quality homemade meals. In addition to buffet offerings, Factory provides catering services for meetings and events. All dishes are prepared in Factory’s own restaurant kitchens by the restaurants’ own chefs, and the menu focuses on diverse, high-quality home cooking. The company currently operates 22 restaurants in Southern Finland and employs around 200 people. CapMan Growth is a leading Finnish growth investor that makes significant investments in entrepreneur-led growth companies with turnover of €10–200 million. CapMan Growth is part of CapMan, which is a leading Nordic private equity investor engaged in active value creation work. CapMan has been listed on the Helsinki Stock Exchange since 2001.
Case published 2.12.2025
Korona Invest – Sale of Innoflame
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
Marina Group – Acquisition of Iisiveneily and Porvoon Venekorjaamo
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
Neste – A EUR 250 million 10-year loan with NIB
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
Aspo – Demerger and finance matters
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
Lenders and Export Credit Agencies – EUR 514.4 million green project financing for Easpring Finland New Materials’ CAM plant
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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