Security & Defence 

Security & Defence 

The security landscape in Europe has fundamentally changed in recent years. Shifting geopolitical realities and accelerated technological development are creating both new opportunities and new challenges for security and defence operators.

Companies in this field must navigate a highly regulated and rapidly evolving environment. They face increasingly complex compliance requirements, heightened scrutiny around investments and ownership, and growing expectations around ethics and responsible business conduct.

Legal advisor to the security and defence sectors

Castrén & Snellman provides top-tier legal services to domestic and international clients operating in the security and defence industries. Our deep industry knowledge helps clients anticipate legal risks and seize strategic opportunities in a changing world.

We advise both private and public sector organisations across the full corporate lifecycle, from early-stage funding and cross-border structuring to strategic partnerships and regulatory risk management.

Our clients include defence sector authorities, defence tech developers, dual-use manufacturers, critical infrastructure operators, public authorities, institutional investors, banks and venture capital and private equity funds. Many are driving innovation in areas such as space, cybersecurity, AI, connectivity and sustainable technologies.

As the go-to supplier of legal services, we advise security and defence operators, as well as their business partners, on matters such as:

Castrén & Snellman is a trusted legal partner in matters where national security, regulation and geopolitical complexity intersect. Our legal advice helps safeguard operational continuity, promote responsible growth, and support the strategic resilience of the security and defence ecosystem.

Latest references

castren snellman general atlantic iceye
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
We advised an international bank syndicate in a EUR 300 million revolving credit facility (RCF) for ICEYE, the world leader in sovereign intelligence from space. The bank-syndicate comprised Nordic and global banks, with Citi and Danske Bank acting as Joint Global Coordinators and Mandated Lead Arrangers. The RCF will support the issuance of guarantees for customer contracts, enable continued business growth, and serve as a liquidity backstop. 
Case published 21.5.2026
We advised the NATO Innovation Fund as lead investor on Kelluu’s EUR 15 million Series A funding round, with participation from Keen Venture Partners, Gungnir Capital, and Tesi. Kelluu is a Finnish deep tech company operating the world’s largest autonomous airship fleet. We advised NIF on this transaction alongside global law firm Latham & Watkins.
Case published 17.4.2026
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