Unique Device Identification

The US public health authority is using unique device identification (UDI), aimed at complete traceability of medical devices. Identification is internationally standardised in line with labelling regulations. Product information must additionally be published in a reference database. UDI is a system for identifying and labelling medical devices with the aim of increasing patient safety.


The Medical Device Regulation (MDR) and the In Vitro Diagnostic Regulation (IVDR) came into force on 25 May 2017. Since 26 May 2019, GS1 has been a designated UDI issuing entity under the MDR and IVDR; provided that no previous designation occurred (see MDR Section 123 (3i) and IVDR Section 113 (3h)). Ongoing updates on the MDR and IVDR are also available on the website of the European Medicines Agency. GS1 Switzerland offers appropriate solutions for global unique labelling of medical devices and in vitro diagnostic medical devices. 

At GS1 Switzerland, we will support you in implementing UDI. 

Important note for the implementation of the UDI:

For medical devices of class I, the indication of the BASIC UDI-DI on the EU declaration of conformity and the technical documentation has been mandatory since 26 May 2021. You can find out more about the BASIC UDI-DI and how it is created on this page.

UDI Overview

GS1 offers comprehensive solutions for meeting UDI requirements. So as not to lose the overview, focus on the following three key areas:


The GS1 identification keys (e.g. GTIN, GLN) are precisely defined sequences of characters of a specific length which facilitate unique referencing in information systems of physical units such as trade items, shipping units, reusable transport containers, locations and service relationships.

EU UDI-requirements


GS1 System

All medical devices and in vitro diagnostic medical devices must have global unique identifiers.

  The standards of the GS1 System support you with UDI compliant identification of your products.


The Basic UDI-DI is the primary identifier of a device model, which is assigned at the level of the device unit of use. It is the main key for records in the UDI database and is referenced in relevant certificates and EU declarations of conformity.
Use the Basic UDI-DI Generator from GS1 to generate your Basic UDI-DI.

Here: Link to the Generator

Watch the tutorial video here: Basis UDI-DI


GMN - Global Model Number 

The global model number (GMN) is used to implement the Basic UDI-DI. The GMN is the GS1 identification key which identifies the model of a device, from which the trade item is derived.

Important note for the implementation of the UDI:

For medical devices of class I, the indication of the BASIC UDI-DI on the EU declaration of conformity and the technical documentation has been mandatory since 26 May 2021. You can find out more about the BASIC UDI-DI and how it is created on this page.

UDI Device Identifier (UDI-DI)
The UDI-DI is a one-time numeric or alphanumeric code which identifies the item (static data).

  GTIN - Global Trade Item Number 
For the UDI-DI, use the global trade item number (GTIN), which is generated on the basis of your global company prefix (GCP) and a serial number. (See GTIN details)

UDI Production Identifier (UDI-PI)

The UDI-PI facilitates traceability using data such as batch number, expiry date, serial number (dynamic data).

  AI - Application Identifier 
For the UDI-PI, use the application identifier (AI). Based on this standard, all data elements are unique and clearly defined: 

-AI (10) lot or batch number (up to 20 alphanumeric characters)
-AI (17) expiry date - YYMMDD 
-AI (21) serial number – up to 20 alphanumeric characters


To read GS1 identification numbers and other information such as best before date, batch or serial number automatically and therefore quickly and error-free, defined data identifiers (AI) and standardised data carriers are used.

EU UDI-requirements


GS1 System

UDI-Carrier (AIDC+HRI)
All UDI (UDI-DI/UDI-PI) information must be placed on the packaging and/or medical device itself, depending on the classification. AIDC + HRI stand for 'automatic identification and data capture' and 'human readable interpretation' respectively.


Automatic identification and data capture/human readable interpretation. GS1 barcodes and symbols are data carriers, comprising of an optical pattern, by which the data is represented and machine read, and the encoded data in human readable writing. The following GS1 data carriers may be used as part of UDI:
- EAN-13
- GS1-128 Barcode
- GS1 DataMatrix
- EPC HF Gen 2, EPC UHF Gen 2

Automatic identification and data capture (AIDC)


The technology for automated data capture. AIDC technology comprises barcode symbols, smartcards, biometrics and RFID.

Human readable interpretation (HRI)
Line in plain writing


Characters, such as letters and numbers, which can be read by humans and encoded in GS1 AIDC data carriers, based on the structure and format of GS1 standards. The line in plain writing is 1:1 the representation of the encoded (user) data. However, the start, stop, data and check characters as well as the symbol check digit are not represented in the line in plain writing.

Linear 1D-Barcodes


GS1 - 128 Barcode  The GS1-128 barcode is suitable for encoding data which goes beyond pure product identification (such as batch, date or weight). The GS1-128 is mainly used in logistics.


EAN-13 Barcode   Only the GTIN (global trade item number) is encoded in the EAN-13 barcode. The EAN-13 barcode is mainly used in retail and other points of sale where cash tills are used.

2D-Matrix Barcodes



GS1 DataMatrix  GS1 DataMatrix is a 2D code for encoding data that goes beyond pure product identification on very small products. This symbol is mainly used in healthcare and for direct part marking (DPM) of parts.

Radio Frequency Identification (RFID)
An RFID tag consists of a circuit (the chip) and an antenna to transmit and receive the stored data. In addition, it may have further storage.


EPC HF Gen 2, EPC UHF Gen 2         The electronic product code (EPC) is an identification system for the identification of physical objects using RFID tags. The EPC is transmitted from tag to read-write device via high frequency or ultra high frequency radio waves.


GS1 standards on data exchange specify how information can jointly be used across the entire network of a supply chain. They provide the basis for electronic business transactions and create transparency by linking the virtual and real worlds.

EU UDI-requirements


GS1 System

As a manufacturer, you are required to provide the master data for your products to the European UDI database (part of the European EUDAMED database).


Our recommendation: use the global GDSN data sharing network to make your UDI data easily available to all users via a single link.

Your benefits


Attractive price


Perfect for beginners


Globally valid number range


Free administration via GTIN Registry

Before starting your UDI-related work, you should consider the following 5 questions. You will see that rather than being an individual contest, UDI is a team effort which concerns your entire value chain.  

  1. Which medical devices are affected by the MDR/IVDR?

  2. Into which classes are these medical devices grouped?
    -Have any changes been made to the different classes?
    -How many medical devices are affected?                                          
  3. Do you already use the GS1 System?
    - Does a GCP (global company prefix) exist?
    - How is GTIN assignment regulated? (GCP required for GMN in EUDAMED/GUDID and/or GTIN)
  4. Is there extensive UDI knowledge in the company?
    - Is there awareness of the regulatory adjustments?
    - Is there awareness of the deadlines?
  5. How is UDI embedded in your company in organisational terms?
    - Do you consider UDI as a project, or does it rest with one person?

5 steps to EU UDI


1. Gain GS1 Switzerland membership                                                                                                                                                   
To use GS1 standards, you need membership with use of the GS1 System (barcodes).

2. Assignement of a Basic UDI-DI
The MDR and IVDR define the Basic UDI-DI as the primary identifier of the device model, which is assigned at the level of the unit of use. It is the main key for records in the UDI database and is referenced in relevant certificates and EU declarations of conformity. Use the GMN – Global Model Number - for assignment of the Basic UDI-DI.

3. Assignement of UDIs

3.1. General requirements
The manufacturer assigns one-off UDIs for his medical devices and maintains these. The UDI may only be placed on the medical device or its packaging by the manufacturer. A UDI is assigned to the medical device itself or its packaging. Higher packaging levels have their own UDI. Each component which is considered a medical device and is commercially available on its own is assigned a separate UDI, unless the components are part of a configurable medical device which is labelled with its own UDI. Shipping containers are excluded from these requirements. The GTIN Registry and MyGTIN help you to organise your GTINs.

3.2. The DI unit of use
The DI unit of use is used to assign the use of a medical device to a patient in cases where the UDI is not indicated on the individual medical device at the level of its unit of use, e.g. if several units of the same medical device are packaged together. To identify your units of use, use the GTIN – global trade item number.

3.3. UDI-DI
The UDI-DI is a one-time numeric or alphanumeric code which is unique to a medical device model and is also used as 'access key' to information stored in a UDI database. The UDI-DI is unique at all levels of product packaging. To identify your medical devices and the available packaging levels, use one GTIN - global trade item number - each. Please note the relevant assignment and update rules (see MDR/IVDR Annex VI, Part C (3) and (6)) when assigning all identification numbers. These are enshrined in the MDR and IVDR on the one hand and on the other, there are GTIN assignment rules for healthcare. 

3.4. UDI-PI
The UDI-PI is a numeric or alphanumeric code used to label the unit of device production. The different types of UDI-PI include serial number, lot number, software identification and the manufacturing or expiry date, or both. If a lot number, a serial number, software identification or an expiry date is indicated on the label, it is part of the UDI-PI. If the date of manufacture is also included on the labelling, this does not need to be incorporated in the UDI-PI. If only the date of manufacture is on the labelling, this must be used as UDI-PI. Use the GS1 application identifier (AI) for this purpose.

4. Selecting the appropriate UDI carrier

In principle, the requirements for UDI carriers listed in the MDR/IVDR must primarily be followed. They are provided in MDR/IVDR Annex VI Part C (4).

The following GS1 barcodes are permitted as UDI carriers:
-EAN-13 Barcode
-GS1 DataMatrix

RFID technology may also be used for the 1D or 2D barcodes. GS1 supports two frequency ranges – ultra high frequency (UHF) from 860 to 960 MHz and high frequency (HF) at 13.56 MHz.

5. Uploading UDI data to EUDAMED
You will need the Basic UDI-DI and all UDI-DIs generated as well as the associated medical device data prior to launch, in order to register your medical devices in the European database on medical devices (EUDAMED – see MDR/IVDR Annex VI Part A). You then continuously update this information. To date, no notification regarding the full functioning of EUDAMED has been published by the European Commission in the Official Journal of the European Union, which means that registration currently is not possible. However, you can already prepare data exchange as per the UDI regulations today.

The EU UDI Timeline

Valid from

The new Medical Device Regulation (MDR) has been postponed by one year as per the resolution of the European Commission of 17 April 2020 and will come into force on 26 May 2021.

The Mutual Recognition Agreement (MRA) between Switzerland and the European Union has also been postponed by a year. Accordingly, MDD medical devices and MDR medical devices may be launched in the EU internal market until 26 May 2021 (without third country requirements).

Click here for the official publication in the Official Journal of the European Commission.

UDI-carrier on label

As of 26 May 2021, placing a UDI carrier on the labelling of your medical devices and at all higher levels of packaging (excluding shipping containers) will be according to assessment of the medical device in one of the following risk classes:

Risk class



MD Class III (MDR Art. 123 (3f)) 26. May 2021
MD Class II (MDR Art. 123 (3f)) 26. May 2023
MD Class I (MDR Art. 123 (3f)) 26. May 2025
IVD Class D (IVDR Art. 113 (3e)) 26. May 2023
IVD Class B & C (IVDR Art. 113 (3e)) 26. May 2025
IVD Class A (IVDR Art. 113 (3e)) 26. May 2027

For reusable products where the UDI carrier has to be applied directly to the product, the deadlines apply 2 years later in each case.

Effects of the Medical Devices Ordinance (MedDO) in Switzerland

Due to a missing MRA (Mutual Recognition Agreement) between Switzerland and the EU, there are particularities for the Swiss market, which have to be considered as a manufacturer, importer or distributor of medical devices.

In Switzerland, the MedDo version of July 1, 2020 (as of May 26, 2021), which only partially adopts European law, has been in effect since May 26, 2021.

The missing MRA affects both imports and exports of medical devices. We focus our communication on imports. For exporting companies, the industry association SWISS MEDTECH has published detailed information.

The communication of the EU and also Switzerland repeatedly refer to the fact that talks are still ongoing and possible developments would be communicated. We will inform you as soon as possible about developments.

Conformity marking and identification number
(MedDO Art. 13 - Conformity marking and identification number)Devices placed on the market in Switzerland or made available on the Swiss market must bear a conformity marking in accordance with Annex 5. The conformity marking presented in Annex V to EU-MDR18 is also a permissible conformity marking.In addition to the CE mark described in Annex V of the EU MDR, Annex 5 of the MedDO also describes a national conformity mark. Both markings are permissible.

Product information
(MedDO Art. 16 - Product information)Product information must be written in all three official languages of Switzerland. Article 16 regulates in which cases the product information may be written in less than the three official languages or in English (paragraph 3).

Information on implantable devices
(MedDO Art. 20 - Information on implantable devices)For implantable products, the manufacturer must provide, in addition to the product information required under Article 16, the information required under Article 18 paragraph 1 EU-MDR33, including the implantation certificate. The implantation certificate must be written in all three official languages of Switzerland.

Registration of Economic Operators                                                                                                                                         (MedDO Art. 55 -Registration of Economic Operators)Manufacturers or their authorised representatives and importers must register the information required by part A of Annex VI to EU-MDR69 with Swissmedic within three months of placing a device on the market for the first time.Application form: Unique identification number according to Art- 55 MedDO (CHRN Swiss Single Registration Number).

Medical Devices Information System
(MedDO Section 2 - Medical Devices Information System)Articles 83 - 92 describe an information system for medical devices. Swissmedic is responsible for this information system and is responsible for drawing up regulations for its use. Data can be obtained from EUDAMED as well as from cantonal electronic systems.

Affixing the UDI                                                                                                                                                                                    The deadlines for affixing the UDI, do not deviate from the EU MDR and are regulated as follows (MedDO Art. 104 - Affixing the UDI):

  • for implantable and class III devices: from 26 May 2021;
  • for class IIa and IIb devices: from 26 May 2023;
  • for class I devices: from 26 May 2025;
  • for reusable devices where the UDI has to be affixed to the product itself: two years after the dates given in letters a–c for the relevant product class.

Appointment of authorised representatives(MedDO Art. 104a - Appointment of authorised representatives)If the manufacturer is domiciled in an EU or EEA state, or if the manufacturer has designated an authorised representative domiciled in an EU or EEA state, that manufacturer must designate an authorised representative in accordance with Article 51 paragraph 1 within the following time periods:


  • for class III devices, class IIb implantable devices and active implantable devices: by 31 December 2021;
  • for non-implantable class IIb devices and class IIa devices: by 31 March 2022;
  • for class I devices: by 31 July 2022.