how do I combine data from different suppliers in one passport

What you must concretely do

A construction company that has a beam rolled from steel supplied by one supplier, coating applied by a second party and the whole thing processed by a third party, ultimately receives one product with one passport. The question that arises: whose data goes into it, and who is responsible if something is not correct? The ESPR (Regulation (EU) 2024/1781) assumes a chain of actors each supplying their part, not one party making it all up.

What is expected of you

Do not rewrite data from earlier links in the chain

Article 38 of the ESPR (requirements for actors in the supply chain) describes that actors in the supply chain keep the information they receive from a previous link available for the next link. For a company with 10 to 100 employees, this practically means that data on the origin and composition of steel coming from the rolling mill are not overwritten or reformulated once the material undergoes further processing. The information travels along, and what is added is new information about the company's own processing step — not a repetition or interpretation of what another party has already established. Which data exactly is needed to keep that chain complete is described on which data must I request from my steel supplier.

One passport, multiple sources

Article 10 of the ESPR (requirements for the digital product passport) describes that the passport contains the information relevant to the product in question, regardless of how many parties have contributed to its creation. For a processing company, this means that the passport of the final product is not automatically a sum of separate sub-passports, but a compiled set of data in which the origin, composition and processing of each link can be traced. Who takes responsibility for this compilation and how it is practically built up is something that is still viewed differently in the sector; what is certain is that the origin of each data point must remain traceable.

Align measurement methods with each other

Article 39 of the ESPR (test, measurement and calculation methods) describes that data included in the passport has been determined according to the methods prescribed for the product in question and the property in question. When two suppliers have determined the same property — for example a mechanical strength value — in a different way, data is created that cannot simply be placed side by side in one passport. For a company that combines semi-finished products from different rolling mills or smelters, this means that the comparability of the underlying measurement method is a point of attention, not only the outcome of the measurement itself.

No data that obscures actual performance

Article 40 of the ESPR (prevention of circumvention and degradation of performance) describes that it is not permitted to present a more favourable picture than the actual performance justifies, either through the composition of data or through the way a product is configured. When combining supplier data, this means that a favourable value from one link in the chain must not conceal an unfavourable value from another link. For a company engaging multiple suppliers, this is particularly relevant to the way partial results are combined into a single figure for the final product.

Where things go wrong in practice

A first recurring situation is that a processing company receives a fully completed data document from one supplier and only an invoice with a material code from another. The passport of the final product is then compiled from a complete and an incomplete part, without this being recorded anywhere.

A second situation: two suppliers use a different unit or test method for what appears to be the same property on paper. The values are placed side by side without anyone checking whether they are actually comparable — resulting in a passport that is internally inconsistent.

A third situation arises when importing from outside the EU: part of the steel comes from a European supplier with a complete passport, another part from a supplier outside the EU with documentation in a different format. How the two relate to each other in one final passport is then a question that is not automatically answered; see also what does the product passport mean if I import steel from outside the EU.

A fourth situation: a supplier provides data under a confidentiality clause, and the processing company is uncertain how this relates to the obligation to pass data on to the next link in the chain. This is particularly relevant for composite products in which multiple suppliers have a share in the final formulation or alloy; see can I agree on an NDA and still comply with the passport.

A fifth situation arises when one of the suppliers, after processing the material, modifies or supplements data without feeding this back to the company compiling the final passport. The result is a passport that is already outdated at the moment of publication.

What you can document

• An overview per supplier of which data have been received, in what form, and at what point — so that for a combined passport it remains clear which part comes from which link in the chain.
• The test method or measurement standard that applies to each piece of received data, recorded separately alongside the value itself, so that comparability between suppliers can be verified afterwards. See also how do I check whether my supplier's data are correct.
• Agreements with each supplier on the form and timing of delivery of passport data, ideally recorded in the purchase contract; a starting point for this is found in how do I record the supply of product passport data in my purchase contract.
• A fixed procedure for the moment when the end product changes form through processing, and what that means for the passport created at that point — explained in what happens to the passport if I process steel into a different product.
• A log of corrections: when a supplier modifies previously supplied data, what the modification involved and whether it has been incorporated into an already compiled passport.
• A fixed contact point per supplier for questions about missing or unclear data, so that there is no need to search again for who is responsible for what every time an issue arises.