Praised by clients for its ‘collaborative style, global reach, and modern approach’, Andersen Legal - Pistiolis - Triantafyllos & Associates Law Firm is noted for its strength in data protection, AI and regulatory matters within the TMT sector. Practice head Themistoklis Giannakopoulos is well‑versed in GDPR compliance, data‑sharing agreements and DPO reporting. Managing partner Theodore Pistiolis advises on IT and EU infringement issues, while Nicholas Zelios is recognised for his ’strong TMT and data expertise’. The ‘invaluable’ and ’insightful’ Climentini Andreadi focuses on AI compliance, while Olga Fakiola joined the team from PwC Greece | Vizas - Grigoriadou and Partners in April 2025, adding depth in technology and cybersecurity frameworks.

Legal 500 Editorial commentary

Testimonials

Collated independently by Legal 500 research team.

'Themistoklis Giannakopoulos continues to be our legal partner and point of contact throughout our co-operation with the law firm. He provides excellent legal counsel, is experienced, knowledgeable and unmatched in the TMT sector.'
‘What makes this practice unique is its deep specialisation in data protection and privacy law, combined with a highly practical, business-oriented approach. The team operates with a clear focus on DPO responsibilities, demonstrating both legal expertise and operational understanding of data governance, risk, and compliance.'
‘The individuals I work with truly stand out because of their exceptional professionalism, deep expertise, and genuine commitment to supporting our needs. What sets them apart from competitors is not just their solid knowledge of data privacy law, but their consistent willingness to help and general approach.'
'Climentini Andreadi has been invaluable. She is always punctual and reliable, never missing deadlines, which creates a strong sense of trust and confidence. Beyond that, she consistently provides insightful input that goes beyond surface-level advice—offering practical, forward-thinking solutions that align closely with our business objectives. Her ability to anticipate challenges and clearly communicate complex data privacy concepts has made a significant difference in how we navigate regulatory requirements.'
'Olga Fakiola is a very experienced professional, addressing our issues with genuine interest and commitment.'
‘The Andersen Legal team has keen expertise in data and AI. Their collaborative style, global reach, and modern approach make them a trusted and forward-looking partner for us.’

Key clients

Netcompany
Plaisio Computers S.A.
Binary Tree S.A.
Attica Group
Aegean Baltic Bank
Brown Hotels
Heronenergy S.A.
Starbucks
SARMED
InfoQuest
Intrakat
EULER HERMES HELLAS

Work highlights

Advised GEK TERNA Group on personal data compliance issues during the Attiki Odos Motorway concession and the sale of TERNA Energy SA to Masdar Group.

Providing GDPR advice and DPO support services to Allianz Greece, addressing all specific needs arising from the acquisition and integration of Evropaiki Pisti.

Advised INMARSAT Group on compliance with Greek e-communications laws and represented its companies before regulatory authorities.

Lawyers

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