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We are a reference in all forensic services, arbitration expertise, accounting expertise, and other advisory and technical assistance services in litigation, arbitration, and risk prevention for companies and individuals.
Technical Assistance in Lawsuits

During a lawsuit, it is not uncommon for the parties to request the Court to produce expert evidence to demonstrate their reasons or their arguments, whether in Public or Private Law. In such cases, the Trial Court indicates a technical professional capable of conducting such evidence, and the party is responsible for indicating another professional with the same background to act as its representative, enabling the expert opinion to be conducted with the impartiality and seriousness that each case requires.


In this circumstance, especially after the case has been decided, our multidisciplinary experts act as Technical Assistant to one of the parties, when a Critical Technical Opinion to the Expert Report is issued, which may be either Concurring, Disagreeing, or Mixed.

Technical Assistance in Arbitration Proceedings

In the course of arbitral proceedings it is common for parties to request the Arbitral Court to produce expert evidence to demonstrate their reasons or their arguments. Because of the flexibility inherent in arbitral proceedings, expert evidence may be provided in various forms, such as with the appointment of an expert by the Arbitral Court, when the parties then appoint technical assistants, only with the production of Technical Opinions by the parties, including Opposing Technical Opinions, in addition to other possible formats, such as the use of the Sachs Protocol.

Whatever the format of the expertise to be performed, Porto & Reis is able to conduct the expert work, enabling the technical work to be conducted with the exemption and seriousness that each case requires. In this circumstance, we act as Technical Assistant for one of the parties, as Independent Experts, when a Technical Opinion of Accounting Nature is issued, as well as Experts for the Arbitration Court.

We act in cases, including as negotiation specialists hired by the parties, in consensus, even before an arbitration proceeding is constituted to present solutions, for example, for disputes arising from contracts of Mergers and Acquisitions (M & A), Calculation of Assets, Economic and Financial Rebalancing, among other types of cases.

Expert Witness in Arbitration Proceedings

During an arbitration proceeding, when the technical issue becomes more theoretical, the parties may ask the Court for Technical Testimony on a certain theoretical aspect to demonstrate their reasons or arguments. In such circumstances, we assess the issue and demonstrate the technical and theoretical basis justifying the claim when we issue an Accounting Technical Opinion, in addition to providing testimony at the hearing.

Technical Report of an Accounting and/or Tax nature

As we are specialists in accounting and tax matters, both technical and doctrinal, we are able to issue Technical Opinions on various topics in the accounting or tax area that involve the various taxes, duties, and fees, whether federal, state, or municipal.

Calculation of Assets, Indemnities, Judgment Liquidations, as well as analysis of issues related to the tax area in all spheres and taxes, being relevant to highlight how discussions related to the amortization of goodwill, identification of tax credits, nature of operations subject to tax incidence, are part of our daily routine.

Previous Technical Expertise

It is not uncommon, in civil or tax procedures, to prepare a Technical Opinion of an Accounting and/or Tax nature, addressing the evidence that justifies the issues under discussion in Administrative, Judicial, or Arbitral Proceedings.


Advance evidence, also known as pre-expertise or pre-constituted expertise, allows legal advisors to have prior knowledge of what the legal or natural persons intend to prove and demonstrate, and to determine the risks associated with the issue under discussion.

Therefore, we also act through the instrument of precautionary evidence production, as an anticipatory measure to the civil process.

Liquidation of Judgment

The materialization of the effort, both client and its legal advisors, results in a judicial or arbitral decision that may require settlement. In such cases, through the correct interpretation of what was decided, we act in the settlement of the amounts of the decisions by analyzing how much was requested and how much was decided, when we will issue a Calculation Statement indicating the potential amounts to be received or paid.

Expertise and sectors

Our professionals have decades of experience in litigation and arbitration expertise in different sectors of activity, such as oil and gas, energy, information technology, consumer goods, industry, services, retail, financial markets, and more.

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