DÍAZ-HEREDERO — Legal & Tax. Gonzalo Díaz-Heredero López, trilingual jurist: tax, tax procedures and civil law.

Legal & Tax

Trilingual jurist (ES · EN · FR)

  • Tax
  • Tax procedures
  • Civil law

Before proposing a solution, I reconstruct the problem: what actually happened, what the available documentation can support, and where the real exposure lies. That analysis is what makes it possible to prevent contingencies, organise the evidence and resolve tax and civil questions on a position that withstands scrutiny — with specific experience in tax procedures.

Currently completing the qualifying programme for admission to the Spanish Bar.

Salus populi suprema lex esto

Let the welfare of the people be the supreme law

Marcus Tullius Cicero · De legibus, III, 3, 8


Documented recognition

Verifiable awards and publications. Every item links to its public source.

15th ISDE International Legal Award 2025

Student category, for the dissertation on the exemption under Article 7 p) of the Spanish Personal Income Tax Act.

13th UCM University Entrepreneurship Awards 2025

Final dissertation category. Score: 96.5/100.

Distinction with honours · Top 1%

Business Administration dissertation (UCM) on AI-assisted analysis of double taxation agreements.

Academic and professional publications

Journal e-pública (University of Zaragoza) and the LEX / Expansión legal portal.


Three core areas

The work concentrates on three fields. Each is approached with the same method: facts, documentation, applicable rules and a defensible position.

Practice areas


Questions I can help with

Most matters do not arrive sorted by subject area, but as a specific problem. These are some of the most frequent ones.

Raising a question does not mean the matter will be accepted: every request is assessed beforehand.


How an enquiry works

A clear sequence, with no automated bookings and no commitment in advance.

  1. Enquiry

    You describe the matter through the form, without attaching any documentation at this first stage.

  2. Suitability assessment

    The request is assessed: whether it falls within the areas of work, whether there is a conflict of interest and whether it can be handled in time.

  3. Scope and terms

    If the matter is accepted, the scope, the format of the work and the terms are communicated before anything starts.

  4. Documentation and delivery

    Only then is the necessary documentation requested and the agreed consultation or written work carried out.

Submitting the form does not mean the matter has been accepted.


Services

Two clearly defined services. If a matter requires further analysis, it is proposed separately before any work is carried out.

Tax consultation

  • Preliminary review of the question raised.
  • A personalised consultation of up to 45 minutes.
  • Analysis tailored to the specific case and to the available documentation.

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Second tax opinion

  • Independent review of a tax question that has already been analysed.
  • Testing of the position taken and identification of alternatives.
  • Assessment of risks, uncertainties and points requiring further analysis.

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Innovation Consulting for Law Firms

Technology, artificial intelligence and automation applied to legal practice.

A B2B line of work for law firms and in-house legal departments that want to adopt artificial intelligence tools without losing control over sources, traceability and professional secrecy. The starting point is never the tool: it is the actual workflow.

Review a workflow


Sector specialisation: energy taxation and regulation

A line of technical specialisation developed in professional practice within the energy sector. It is not a stand-alone sector boutique: it is evidence of specialist knowledge in one of the most technical areas of Spanish tax law.

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