how do I process data from multiple suppliers for the same alloy in one passport

Each supplier provides its own part of the data

When an alloy comes from multiple suppliers, each supplier provides the data on the material it has itself supplied, and those data are combined in a single passport without being reduced to a single average or estimate. The passport concerns a specific product or a specific batch, and the origin of the raw materials in it must remain traceable to the actor who provided the data. In practice, this means that a combined passport contains multiple source data sets side by side — for example, the share of recycled material per supplier, or the origin of alloying elements per batch — instead of a single aggregated or averaged figure from which it is no longer possible to see where it came from.

Who this applies to and what it does not

This is particularly relevant for manufacturers and processors who purchase aluminium from different foundries, rolling mills or traders and use it to make a single end product or a single combined batch. The question then is how the data from those different sources relate to each other in the final passport. It is not about what must happen if a supplier provides no data at all — that is a different issue, described under what to do if a supplier does not provide the data. It is also not about the situation in which the aluminium itself is already a physical mixture of scrap with unknown or varying origin; that situation, where the mixing is already in the material itself before it arrives at the manufacturer, is addressed under data for mixed batches from mixed scrap. The subject here concerns specifically the administrative side: multiple separate, traceable data sets that come together in a single passport, not the melting of material with unknown composition.

When this will apply

The obligation to have a digital product passport for aluminium follows from a delegated act that has not yet been published. The ESPR Work Plan 2025-2030 lists aluminium as one of the product groups for which such an act is being prepared, with an expectation around 2027, but no fixed date has been set. Until that act is in place, there is no obligation to draw up a passport with combined supplier data. What is already determined, however, is the framework within which this will have to happen: Article 38 of the ESPR requires actors in the supply chain to provide the data necessary to comply with the information obligations, and Article 10 sets out the requirements that the passport as a whole must meet. Once the delegated act for aluminium has been published, that date will be stated here.

How this is built in practice

If you are already working with multiple suppliers for the same alloy, it is advisable to start by separating the data flows per supplier rather than letting them merge into a single average figure. In practice, this involves a few steps. First, it is established what data each supplier provides separately on its part of the material — composition, origin, share of recycled material, any processing. Next, it is determined how those batches relate to each other in the end product: are they separate charges that remain separately identifiable, or is the material already combined at the foundry. In the first case, the passport can show the data per source side by side; in the second case, the question becomes relevant how to handle a mixed result, which touches on the approach for mixed batches. After that, it is important to establish in advance with each supplier what data will be provided, when and in what form — this is best done as a fixed part of the purchasing agreements, as described under establishing passport data in the purchasing contract, so that there is no need to search for missing data after the fact. It is also advisable to determine in advance which data are precisely needed per supplier, which can be found by asking which data are requested from an aluminium supplier. Finally, it remains advisable to verify the supplied data before they end up in the passport, especially when multiple sources are combined and an error from one supplier can affect the entire passport.

What this is based on

Article 38 of the ESPR (Regulation (EU) 2024/1781) places the obligation on actors in the supply chain to supply the data needed for the product passport, which forms the basis for the idea that each supplier is responsible for his own part. Article 10 describes the requirements that the passport as a whole must meet, including the traceability of data. Article 39 concerns the test, measurement and calculation methods used to establish data, which becomes relevant once multiple source data come together that must be measured according to the same method to be comparable. Article 40 focuses on preventing circumvention and deterioration of performance, which touches on the concern that combining data must not lead to a more favourable picture than the actual composition of the material justifies.

Anyone who wants to prepare for this in their own procurement starts by mapping out the current suppliers and the data that they can or cannot already supply, and then establishes how that data remains identifiable per batch in their own administration — before the moment a passport becomes mandatory.

What this is based on

The regulation itself is on EUR-Lex. We refer per statement; you do not have to take our word for it.

What you must concretely do

What is expected of you

An aluminium semifinished product is often not the product of a single supplier. A profile may have been cast from an alloy whose base material comes from multiple smelters or scrap batches, and a foundry regularly mixes ingots of different origin with the same alloy number. Anyone compiling a product passport from this must bring those different sources together into one whole without the origin of the data becoming unclear.

Keeping data traceable per supplier

Article 38 of the ESPR (Regulation (EU) 2024/1781) describes that actors in the supply chain supply the information needed to compile the passport. This does not mean that all supplier data may be merged into one undifferentiated figure: the origin of each part of the information remains relevant in practice, especially when it later turns out that one of the batches has supplied incorrect data. For a company of 10 to 100 employees, this means that a simple link between purchase batch, supplier and the final value in the passport must be recorded somewhere — even if only in a purchase register or production slip.

One combined result, with a traceable calculation

Article 10 of the ESPR sets requirements for the content and reliability of the digital product passport. When multiple batches with the same alloy are combined into one product batch, a single combined value is created — for example for recycled material content or for composition. That combined value must be traceable back to the underlying batches. For a medium-sized company, this is often a mathematical issue: a weighted average based on quantities, not a simple arithmetic average of percentages. How that calculation was made is part of what must be demonstrably shown.

Using the same measurement and calculation method

Article 39 of the ESPR concerns the test, measurement and calculation methods used to determine data. If supplier A calculates the recycled content in a different way than supplier B, a product passport emerges in which apples and oranges have been combined into a single figure. For companies working with multiple suppliers, this means that combining data is not just a matter of arithmetic, but also a control: is the underlying method comparable? This is not always visible without asking.

No deterioration of data through hidden mixing

Article 40 of the ESPR describes the prevention of circumvention and of deterioration of performance. This also affects the situation in which a less favourable batch (for example with a lower recycled aluminium content) is "hidden" in a larger, more favourable batch, so that the combined product passport appears more favourable than the actual composition of each part. For day-to-day practice, this means that averaging in itself is not the problem — it happens continuously in the metals industry — but that the way in which averaging is done must remain traceable and defensible.

Where things go wrong in practice

A foundry melts ingots from three suppliers into one casting batch, but product passports or data sheets have only been received from two suppliers. The third batch is filled in on the basis of an estimate — and that estimate is not recorded anywhere as an estimate.

A profile manufacturer purchases the same alloy (for example EN AW-6060) from two suppliers, one with high recycled content and the other with mainly primary aluminium. In the product passport of the end product, a single average percentage is shown, calculated on the basis of number of deliveries instead of on the basis of actual quantities processed — with a distorted result.

An importer combines material from a supplier outside the EU with material from a European supplier. The two underlying dossiers have been drawn up according to different definitions of "recycled material", without anyone noticing that difference before the data ended up together in one product passport.

A subcontractor who carries out part of the melting process is assumed to use the same calculation method as the contracting company. Upon inquiry, this turns out not to be the case — and it is no longer possible to determine which part of the final batch was based on which assumption.

A company keeps supplier data per purchase order, but not linked to the production batch in which they were processed. When the product passport needs to be drawn up, it is no longer possible to reconstruct which supplier belonged to which batch of end product.

What you can document now

A summary per production batch of which suppliers and which quantities were processed in it, including the date and the alloy number.
The underlying supplier data itself, per delivery, so that a combined value can later be traced back to its sources. See also what data you can request from your aluminium supplier for what belongs in it.
The calculation method used to arrive at a combined value (weighted average by quantity, with the formula used or spreadsheet kept as an attachment).
A comparison of the measurement and calculation methods used by the different suppliers, with a note where those methods differ.
Agreements with suppliers on the form and frequency of data delivery, recorded as described in recording the supply of product passport data in the purchasing contract.
A note for batches whose origin cannot be fully traced, with the approach followed for this — relevant when some of the material comes from mixed scrap batches .
A fixed procedure for checking incoming supplier data before it is included in a combined calculation, as discussed in checking your supplier's data for accuracy.

This is not legal advice. This page provides general information on the legislation that this platform covers. We do not know your situation. If in doubt about your own case, consult a lawyer or the competent supervisory authority.

Written with AI based on the sources above, checked by a human on 2026-09-05. Is something incorrect? Let us know — corrections are prioritised.