Appraisal in authenticity matters

The parties propose names; failing agreement, the tribunal chooses from among the experts accredited by OIMAP or other recognised experts. The expert declares independence and any links, and accepts the tribunal's code of ethics. The expert may not have worked for one of the parties in the previous three years.

The tribunal may appoint several experts, for example an art historian and a scientist, or a single expert in charge of coordinating the specialists.

The mission specifies the questions put: is the work by the artist to whom it is attributed, from what period, has it been restored, how does its provenance fit into the known history? It sets a time limit, a budget and arrangements for access to the work.

The expert combines visual examination, comparison with reference works, archival research, material analyses (pigments, supports, patinas) and imaging (infrared, X-rays, tomography). The analyses are carried out by accredited laboratories.

The expert submits a draft report to the parties, who may make observations. The expert answers them in the final report. This adversarial phase guarantees fairness. The parties may bring in their own experts, who debate with the tribunal's expert at the hearing.

The report is one item of evidence among others. The tribunal may depart from it, giving reasons for its decision. A clear, structured and cautious report is very likely to be followed.

The cost of an authenticity appraisal ranges from €6,000 to €60,000 depending on the extent of the analyses. It is advanced by the parties in equal shares, then allocated by the award. To reduce the cost, the parties may agree on a programme of analyses limited to the essential points.

The OIMAP certification file, where one exists, may dispense with certain analyses: the tribunal may draw on it, with the parties' agreement, to go faster.