The Budapest office of Siegler Bird & Bird Ügyvédi Iroda provides comprehensive TMT and regulatory advice, with a significant presence across the technology, data, and e-commerce sectors. The firm stands out for its high-calibre advice on cybersecurity compliance, becoming a go-to for companies seeking guidance on EU-wide NIS2 compliance strategy. The team provides continuous, high-value support for major mobile network operators, fast-growing SaaS tech start-ups, and advises on high-stakes regulatory issues across data protection, consumer, and telecoms law. The team is co-led by Bálint Halász, whose practice centres on IT and telecoms, and Ádám Simon, who advises on cross-border cybersecurity and high-value IT transactions. They are ably supported by Adél Gelencsér, who handles complex electronic communications regulation and engages directly with national media and telecoms authorities.
Legal 500 Editorial commentary
Accolades
Client satisfaction: Lawyer & team quality
Client satisfaction: Billing & efficiency
Client satisfaction: NPS ®
Testimonials
Collated independently by Legal 500 research team.
- ‘Ádám Simon is our contact when it comes to legal matters concerning IT and cybersecurity. He is highly experienced and knows our business well, which is a real advantage.’
- 'What really sets them apart is the depth of the team. We never feel like they are short of expertise.'
- ‘Ádám Simon and his team have been supporting us on a very important IT transition project for about 5 years now and they’ve been consistently great throughout.'
- 'Their ability to distil dense regulatory content into concise, practical recommendations is a standout feature.’
- ‘The firm’s deep regional expertise, particularly in navigating complex frameworks, allows them to offer guidance that is both locally grounded and strategically aligned with EU-wide compliance standards.'
- 'What sets this practice apart is its responsiveness and precision—they deliver clear, actionable advice with impressive turnaround times, which is invaluable in a fast-moving regulatory landscape.’
Key clients
- Yettel
- Bitrise
- Viber
Work highlights
Supported one of Hungary's largest mobile network operators, Yettel, with data protection and IT commercial matters, offering guidance on a range of complex issues.
Supported the Bitrise internal legal team in navigating the rapidly changing and intricate legal challenges arising from the company's SaaS business.
Represented a leading cross-platform messaging application provider, Viber, successfully during competition control proceedings by the Hungarian Competition Authority.
Lawyers
Leading partners
The strongest partners in their field, leading on market-leading deals and endorsed by peers and clients alike.
Next Generation Partners
Junior partners with significant recognition from clients and peers in the market and key roles on multiple matters.
Practice head
Bálint Halász; Ádám Simon
Other key lawyers
Adél Gelencsér