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
Ugly Duckling Ventures – EUR 6.5 million funding round of Skyfora
We advised lead investor Ugly Duckling Ventures on the EUR 6.5 million funding round of Skyfora. The round also included Eviny Ventures, LUMO Labs and EIC Fund, alongside non-dilutive funding from Business Finland. The investment will support the commercial scale-up of Skyfora’s weather intelligence solutions, the expansion of partnerships with telecom operators, forecasting providers and meteorological institutions, and the continued growth of the team. Skyfora is a Finnish company developing high-resolution weather data solutions using patented technology that extracts atmospheric data from GNSS receivers embedded in existing infrastructure, such as telecom networks. By unlocking previously untapped data sources, Skyfora enables the next generation of AI-driven weather forecasting and supports improved decision-making across weather-sensitive industries. Ugly Duckling Ventures is a Copenhagen-based venture capital firm focused on early-stage Nordic B2B technology companies, with an emphasis on medtech, resilience tech and business services.
Case published 10.6.2026
castren snellman general atlantic iceye
General Atlantic – ICEYE’s EUR 1 Billion Series F Funding Round
We advised General Atlantic as the lead investor on ICEYE’s EUR 1 billion series F funding round, valuing the company at over EUR 10 billion. ICEYE raised EUR 450 million (USD 520 million) in a primary Series F funding round led by General Atlantic. Additional investors included Solidium, Tesi, Varma, Ilmarinen, Lifeline Ventures, Nokia, Qatar Investment Authority (QIA) and TCV. Together with a secondary placement, the total fundraising exceeds EUR 1 billion. ICEYE is the world leader in sovereign intelligence from space, providing continuous monitoring capabilities to detect and respond to changes in any location on Earth. The company operates the world’s largest and most advanced Synthetic Aperture Radar satellite constellation. General Atlantic is a leading global investor with more than four and a half decades of experience providing capital and strategic support for over 885 companies throughout its history. As of March 31, 2026, General Atlantic manages approximately USD 126 billion in assets across its investment strategies. We advised General Atlantic on this transaction in collaboration with the international law firm Paul, Weiss, Rifkind, Wharton & Garrison.
Case published 9.6.2026
Oomi Solar – Sale of a Solar Power Plant and Battery Energy Storage Project
We advised Oomi Solar Oy on the sale of a solar power park and battery energy storage project to Tuulipolar Oy. The transaction concerned a 24 MWp solar power plant and a 36 MW / 70 MWh battery energy storage system (BESS) to be constructed in Tornio. Tuulipolar Oy will act as the owner and operator of the plant, while Oomi Solar Oy will be responsible for its design and construction. The project will form the world’s northernmost industrial hybrid power plant, contributing to Finland’s green energy transition by increasing renewable energy production and electricity storage capacity in Northern Finland. The hybrid solution enables optimization of production as well as active participation in electricity markets and reserve services, improving the project’s profitability and supporting the balance of the electricity system year-round. Electricity production from the hybrid plant is expected to begin in 2028. Oomi Solar Oy is a Finnish renewable energy expert with experience from nearly 200 MW of installed solar capacity. The company helps businesses and communities accelerate the green transition by offering comprehensive solutions, including solar power plants, energy storage systems, and related lifecycle services from project development to maintenance. Oomi Solar Oy employs more than 20 energy professionals and delivers solar power projects across Finland. The company’s vision is to be Finland’s most desired partner for solar energy and energy solutions.
Case published 5.6.2026
United Bankers – Sale of three care properties
United Bankers – Sale of three care properties
We advised United Bankers on the sale of three care properties to Kinland AS. The buildings were completed between 2021 and 2022 and meet high technical and environmental standards. All three properties are fully leased. The portfolio has a weighted average unexpired lease term of 13 years.
Case published 1.6.2026
Hiab acquisition financing
Hiab – Financing for USD 1,035 million acquisition of Labrie Environmental Group
We are advising Hiab Corporation in the financing for its USD 1,035 million acquisition of Labrie Environmental Group, a leading North American refuse collection vehicle (“RCV”) manufacturer, from Wynnchurch Capital, L.P. Hiab Corporation (Nasdaq Helsinki: HIAB) is a leading provider of smart and sustainable on-road load handling solutions, with 2025 sales of approximately EUR 1.6 billion and approximately 4,000 employees, operating through a global network spanning over 100 countries. Labrie Group is a leading North American provider of RCVs, employing approximately 1,200 people. 
Case published 1.6.2026

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