> For clean Markdown of any page, append .md to the page URL. > For a complete documentation index, see https://tieback.io/docs/llms.txt. > For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://tieback.io/docs/_mcp/server. # Supply Chain Tier > A position in a supply chain measured by distance from the organisation placing a product on the market, where tier 1 is a direct supplier and higher tiers are progressively more remote, used to describe where product passport data originates and where contractual reach ends. ## Definition A position in a supply chain expressed as distance from the organisation that places the finished product on the market. Tier 1 is an organisation that supplies that party directly. Tier 2 supplies tier 1, tier 3 supplies tier 2, and so on upstream towards raw material production. The numbering is relative to the organisation doing the counting and is not a property of the supplier itself. ## Expanded Explanation Tiering is a way of talking about two different things at once, and its usefulness comes from the fact that they usually diverge. The first is **where information originates**. In most manufactured products the information a Digital Product Passport needs is generated across several tiers: material identity and origin far upstream, processing and treatment in the middle, assembly and lot identity at tier 1, and declared claims at the party placing the product on the market. The second is **where contractual reach ends**. Most organisations have contracts only with tier 1. Data requests beyond that travel by influence, nomination or commercial pressure rather than by contractual right, and they lose fidelity at every hop. The gap between those two facts is the central difficulty of supplier data programmes. The party that carries the legal duty typically originates the least data, and the parties that originate the most sit beyond its contractual boundary. Tier numbering is also relative, which is a frequent source of confusion between organisations. A dyehouse that is tier 2 to a brand is tier 1 to the garment factory. Stating whose supply chain is being counted is part of stating the tier. ## Why It Matters Passport programmes routinely address their data requests to tier 1 because tier 1 is who they know. Tier 1 frequently does not hold the requested information and either declines, guesses, or passes on an unverified figure. Identifying the originating tier for each data requirement, and routing the request there, is what turns supplier engagement from a survey exercise into a data supply chain. Tiering also drives honest measurement. Coverage reported as a proportion of suppliers, or of product lines, systematically flatters. Coverage weighted by volume placed on the market reflects actual exposure. ## Relationship to Digital Product Passports The passport is published by one party but assembled from many. Publication does not transfer authority away from the tier that generated a value. Recording which tier originated each field, and what evidence that tier holds, is what allows a passport to be defended when a value is challenged. ## Common Misconceptions #### Tier 1 is the supply chain Tier 1 is the tier the organisation contracts with, not the tier that knows the most. Assembly suppliers typically originate lot and site data and very little else. #### Tier numbers are absolute labels Tier numbering is relative to the organisation counting. The same facility can be tier 1, tier 2 or tier 3 depending on whose chain is being described. #### A supplier declaration from tier 1 covers upstream facts A declaration is only as good as the knowledge behind it. A tier 1 supplier restating an upstream figure it cannot substantiate adds a hop without adding assurance. ## Related Terms * [Product Traceability](/docs/knowledge-base/glossary/product-traceability) * [Authoritative Source](/docs/knowledge-base/glossary/authoritative-source) * [Economic Operator](/docs/knowledge-base/glossary/economic-operator) * [Source of Truth](/docs/knowledge-base/glossary/source-of-truth) * [Data Quality](/docs/knowledge-base/glossary/data-quality) ## Related Knowledge Base Articles * [How to Prepare Suppliers for Digital Product Passports](/docs/knowledge-base/implementation/how-to-prepare-suppliers-for-digital-product-passports) * [What Data Goes in a Digital Product Passport, and Where Does It Come From?](/docs/knowledge-base/digital-product-passports/what-data-goes-in-a-digital-product-passport) * [Digital Product Passports for Textiles and Apparel: What Companies Need to Know](/docs/knowledge-base/industry-guides/digital-product-passports-for-textiles-and-apparel) ## Related Articles * [Product Traceability](/docs/knowledge-base/glossary/product-traceability) * [Battery Passport](/docs/knowledge-base/glossary/battery-passport) * [Digital Product Passport](/docs/knowledge-base/glossary/digital-product-passport) * [EPCIS](/docs/knowledge-base/glossary/epcis) * [Product Identifier](/docs/knowledge-base/glossary/product-identifier) * [Resolver](/docs/knowledge-base/glossary/resolver) * [What Data Goes in a Digital Product Passport, and Where Does It Come From?](/docs/knowledge-base/digital-product-passports/what-data-goes-in-a-digital-product-passport) * [Who Needs a Digital Product Passport?](/docs/knowledge-base/digital-product-passports/who-needs-a-digital-product-passport) ## See Also * [Implementation](/docs/knowledge-base/implementation/overview) * [Industry Guides](/docs/knowledge-base/industry-guides/overview) ## References * Regulation (EU) 2024/1781 establishing a framework for the setting of ecodesign requirements for sustainable products: [https://eur-lex.europa.eu/eli/reg/2024/1781/oj](https://eur-lex.europa.eu/eli/reg/2024/1781/oj) ## About This Article About This Article
Last Reviewed
2026-08-09
Next Scheduled Review
2027-08-09
Article Version
1.0
tieback Knowledge is a continuously maintained reference library covering Digital Product Passports, product traceability, product compliance and related regulations. Articles are reviewed regularly as legislation, standards and implementation guidance evolve. ## Related Docs * [Glossary](/docs/knowledge-base/glossary/overview) * [Implementation](/docs/knowledge-base/implementation/overview) * [Industry Guides](/docs/knowledge-base/industry-guides/overview)