Understanding GTINs, GLNs, and GS1 Identifiers for DPPs

The GS1 Identification System Overview

The GS1 identification system is a comprehensive framework of standardised identifiers designed to uniquely identify products, locations, assets, and entities across global supply chains. Developed over more than five decades, this system underpins the barcode infrastructure used in retail, healthcare, logistics, and manufacturing worldwide.

For Digital Product Passports, the GS1 identification system provides the foundational layer that connects physical products to their digital identities. While the GTIN is the most familiar GS1 identifier, several other identifier types play important roles in DPP ecosystems, from identifying manufacturing locations to tracking logistics units through complex supply chains.

Understanding the full range of GS1 identifiers and their interrelationships helps businesses design DPP systems that capture not just product identity but the complete context of where, how, and by whom each product was made, distributed, and ultimately recycled.

GTIN: Identifying Products

The Global Trade Item Number (GTIN) is the most widely used GS1 identifier and the primary product identifier for Digital Product Passports. GTINs uniquely identify trade items, any product or service upon which there is a need to retrieve pre-defined information and that may be priced, ordered, or invoiced at any point in the supply chain.

GTINs exist in four formats to accommodate different use cases:

• GTIN-8, An eight-digit identifier for very small products with limited label space, such as small confectionery items or cosmetic samples.
• GTIN-12, A twelve-digit identifier primarily used in North America, also known as the Universal Product Code (UPC).
• GTIN-13, A thirteen-digit identifier used worldwide, corresponding to the European Article Number (EAN). This is the most common format for consumer products.
• GTIN-14, A fourteen-digit identifier used for trade units, cases, and pallets, outer packaging rather than individual consumer units.

For DPP purposes, the GTIN identifies the product model or configuration. When combined with a serial number (GS1 Application Identifier 21), it creates an SGTIN that uniquely identifies individual units. The GTIN is the identifier most commonly encoded in GS1 Digital Link URIs for DPP data carriers.

Every business placing products on the EU market under ESPR scope will need valid, registered GTINs for those products. For many manufacturers and brands, this infrastructure is already in place. For others, particularly smaller producers, artisans, or businesses that have historically sold through channels that did not require barcodes, obtaining GTINs is a necessary first step towards DPP compliance.

GLN: Identifying Locations and Organisations

The Global Location Number (GLN) is a thirteen-digit GS1 identifier used to identify physical locations (such as factories, warehouses, and retail stores) and legal entities (such as companies, subsidiaries, and government agencies). While less visible to consumers than GTINs, GLNs play a vital role in DPP ecosystems by providing standardised identification for the organisations and facilities involved in a product's lifecycle.

In a DPP context, GLNs can identify:

• The manufacturing facility where a product was produced, providing traceability to a specific factory or production site.
• The brand owner responsible for the product, the legal entity that bears regulatory responsibility under ESPR.
• Distribution centres and logistics hubs through which the product passed during its journey to market.
• Retail locations where the product was sold, if relevant to warranty or recall tracking.
• Recycling and waste processing facilities that handle the product at end of life.

ESPR requires that Digital Product Passports include information about the economic operators responsible for a product. GLNs provide a standardised, verifiable way to identify these operators. Rather than relying on company names, which can be ambiguous, translated differently across languages, or shared by unrelated entities, a GLN unambiguously identifies a specific legal entity or physical location in the GS1 global database.

Businesses that already participate in GS1 data exchange, through EDI, EPCIS, or GDSN, likely have GLNs assigned to their key locations and legal entities. Those that do not should obtain GLNs as part of their DPP preparation, as regulatory reporting and supply chain data exchange will increasingly require standardised location and entity identification.

SSCC: Identifying Logistics Units

The Serial Shipping Container Code (SSCC) is an eighteen-digit GS1 identifier used to uniquely identify logistics units, individual shipping containers, pallets, parcels, or any other grouping of products for transport. While the SSCC does not appear directly in consumer-facing DPP data carriers, it plays an important role in the supply chain traceability that supports DPP completeness.

When products are shipped from a factory to a distribution centre, or from a distribution centre to a retailer, they are typically grouped into logistics units. Each logistics unit carries an SSCC, usually encoded in a GS1-128 barcode on a shipping label. This SSCC links the logistics unit to advance shipment notices (ASNs) and other supply chain documents that describe its contents.

For DPP traceability, SSCCs enable the tracking of product movements at the logistics level. By linking SSCCs to the GTINs and serial numbers of the products they contain, businesses can reconstruct the complete distribution history of any individual product, which warehouse it passed through, which truck carried it, when it arrived at each location, and who handled it at each stage.

This logistics-level traceability becomes particularly relevant for DPP use cases involving provenance verification, import compliance, and recall management. If a product defect is discovered, SSCC-level tracking allows businesses to identify exactly which logistics units are affected and where they are in the supply chain.

GIAI, GRAI, and Asset Identifiers

Beyond products, locations, and logistics units, GS1 provides identifiers for returnable assets, individual assets, and service relationships. While these are less central to DPP compliance, they can support specialised use cases within the broader DPP ecosystem.

The Global Individual Asset Identifier (GIAI) uniquely identifies a specific physical asset, a piece of equipment, a vehicle, a tool, or any other tangible item that a business wishes to track. For DPP purposes, GIAIs could identify durable equipment that carries a Digital Product Passport, particularly in industrial and construction contexts where products may not have traditional retail GTINs.

The Global Returnable Asset Identifier (GRAI) identifies reusable transport items such as pallets, crates, kegs, and containers. In circular economy applications, GRAIs could track the lifecycle of reusable packaging, linking each reuse cycle to environmental impact data in a packaging DPP.

These supplementary identifiers illustrate the breadth of the GS1 system. While GTINs and GLNs are the primary identifiers for DPP compliance, the full GS1 toolkit provides standardised identification for virtually every entity that might appear in a product's lifecycle story, from the raw materials that enter a factory to the recycled outputs that emerge from an end-of-life processing facility.

Application Identifiers: Adding Context to GS1 Data

GS1 Application Identifiers (AIs) are standardised prefixes that define the meaning and format of the data that follows them. In barcode and data carrier encoding, AIs tell scanning systems how to interpret each data element. For DPP applications, several AIs are particularly important.

The key Application Identifiers for DPP data carriers include:

• AI 01, Global Trade Item Number (GTIN). The primary product identifier.
• AI 10, Batch or lot number. Identifies the production batch for traceability.
• AI 11, Production date (YYMMDD format). Records when the product was manufactured.
• AI 17, Expiry date (YYMMDD format). Indicates when the product should no longer be used.
• AI 21, Serial number. Uniquely identifies an individual product unit.
• AI 235, Third-party controlled serial number. Used in regulated serialisation schemes.
• AI 8010, Component or part identifier. Identifies a component within a larger product.

In a GS1 Digital Link URI, these Application Identifiers become URL path elements. AI 01 becomes /01/, AI 21 becomes /21/, and so on. This direct mapping between barcode AIs and URL path components ensures consistency between traditional barcode scanning and web-based DPP access.

Understanding Application Identifiers is essential for designing data carriers that encode sufficient information for DPP compliance. A data carrier that includes only the GTIN (AI 01) provides model-level identification. Adding a serial number (AI 21) enables item-level identification. Including a batch number (AI 10) and production date (AI 11) provides batch-level traceability context.

How GS1 Identifiers Work Together in a DPP Ecosystem

The power of GS1 identifiers lies not in any individual number but in how they work together to create a complete, interconnected picture of a product's identity and journey. In a well-implemented DPP ecosystem, multiple GS1 identifiers collaborate to provide comprehensive traceability.

Consider a concrete example. A textile manufacturer produces a batch of cotton shirts. Each shirt carries a QR code encoding a GS1 Digital Link with the product's GTIN (AI 01) and serial number (AI 21). The manufacturing facility is identified by its GLN. The cotton fibre supplier is identified by their GLN. The batch of cotton used is tracked by its lot number (AI 10). The shipping container carrying shirts to the distribution centre is identified by its SSCC.

When a consumer scans the QR code on their shirt, the ESPR-compliant Digital Product Passport can display the product's sustainability data, material composition, care instructions, and end-of-life guidance. Behind the scenes, the DPP system can trace the shirt back through the distribution chain (via SSCCs), to the manufacturing facility (via GLN), to the specific production batch (via lot number), and potentially to the raw material supplier (via their GLN).

This layered traceability, from individual item through production batch through manufacturing location through supply chain, is precisely what the ESPR envisions. And it is made possible by the systematic use of GS1 identifiers at every stage of the product lifecycle.

Getting Started with GS1 Identifiers for DPP

For businesses preparing for DPP compliance, the path to effective GS1 identifier usage begins with an assessment of your current identification infrastructure and a plan for addressing any gaps.

Start by answering these key questions:

• Do all of your ESPR-scope products have registered GTINs? If not, which products need new GTIN assignments?
• Do your key locations, manufacturing facilities, distribution centres, head office, have GLNs? If not, obtain them from your national GS1 organisation.
• Will your product categories require item-level serialisation? If so, what serial number assignment strategy will you use?
• Do you currently use GS1 standards in your supply chain (barcodes, EDI, EPCIS)? If so, how can your existing infrastructure be extended to support DPP data flows?
• Do you have a data carrier strategy? Which GS1 Application Identifiers will you encode in your product QR codes?

Once you have answered these questions, you can build a phased implementation plan that starts with the basics, ensuring GTINs are in place and generating GS1 Digital Link QR codes, and progressively adds serialisation, location identification, and supply chain traceability as regulatory requirements and business needs evolve.

Tools like MyProductPassport accept GS1 identifiers as core product data, automatically constructing compliant Digital Link URIs and generating the data carriers needed for ESPR compliance. This allows businesses to focus on the strategic and operational aspects of DPP readiness while the technical identifier infrastructure is handled by the platform.