About us

We are a boutique law firm specialised in state aid.

In our practice at the European Commission and the EFTA Surveillance Authority we have repeatedly found that the few state aid experts were often principally advising larger clients. Clayton & Segura is a highly specialised law firm which provides legal advice to public bodies, smaller companies and law firms without a state aid practice.

We are committed to the respect of the highest ethical standards. We also believe that expertise should not exclude pragmatism and the achievement of simple solutions. Having worked within the decision-making bodies we are best placed to advise our clients.

From an office located in the heart of the EU district, we are easily accessible and ideally placed to maintain and develop our many contacts at the European Commission and the EFTA Surveillance Authority.

We are able to provide legal advice on EU and EEA matters regarding state aid and related internal market questions in English, French, German and Spanish.

Marianne Clayton contact

Marianne Clayton

Paris Bar

Brussels Bar (List E)

Tel: (+) 32 473 93 57 93

Email: mclayton@claytonsegura.com
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Maria Segura Catalan contact

Maria J. Segura Catalán

Madrid Bar

Brussels Bar (List E)

Tel: (+) 32 486 475 375

Email: msegura@claytonsegura.com
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Marianne Clayton specialises in the fields of competition and state aid. Former senior officer at the Competition and State Aid Directorate of the EFTA Surveillance Authority, she has also gained extensive experience at the European Competition Departments of major international law firms.

She is bilingual in French and English.

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Work experience

  • 2006-2012: Senior Officer – Competition and State Aid Directorate - EFTA Surveillance Authority
  • 2001-2005: Senior Associate - Bredin Prat - Brussels
  • 1998-2000: Associate – Freshfields Bruckhaus Deringer - Paris

Education

  • 1996: Ecole de formation du Barreau de Paris – Bar school
  • 1995 : DESS Droit du marché commun - Université Paris I – La Sorbonne
  • 1994 : Diplôme du Centre Universitaire d’études des Communautés européennes – Paris I - La Sorbonne
  • 1993 : Maitrise de Droit privé – Université Paris I – La Sorbonne LLB – King’s College London

Maria Segura, former Deputy Director of the Competition and State Aid Directorate of the EFTA Surveillance Authority, has many years of practice in the field of state aid. She has gained a wide ranging experience in the defence of state aid decisions before the Courts. She also advises clients in EEA/EU law.

She speaks English, German, French and Spanish.

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Work experience

  • 2009–2012: Deputy Director – Competition and State Aid Directorate – EFTA Surveillance Authority
  • 2004–2008: Senior Officer – Competition and State Aid Directorate – EFTA Surveillance Authority
  • 2002-2003: State Aid administrator – DG Competition European Commission
  • 2000-2002: Associate – Freshfields Bruckhaus Deringer – Berlin
  • 1999-2000: Stagiaire – Legal Service – European Commission

Education

  • 2000: LL.M Eur. - Europa Institut – Universität des Saarlandes -Thesis on recovery of unlawfully granted state aid
  • 1998: Certificate of European Studies – Universität des Saarlandes
  • 1996: Diploma Computers and Law -University of Vienna – Center for applied informatics
  • 1995: Law degree (Licenciatura en Derecho). Specialisation: European Law – University of Zaragoza
  • 1995: Maitrise en Droit (eq.) – Université de Pau et Pays de L’Adour – Erasmus programme
  • Welcome

    Clayton & Segura brings together expertise on regulatory processes with a deep understanding of its clients' needs.

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  • The clients

    Clayton & Segura offers specialised state aid advice to public authorities, companies and law firms.

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  • The services

    Clayton & Segura are state aid expert lawyers offering highly specialised services.

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