The EU Declaration of Conformity is one page. Sometimes two. It is the simplest document in your entire regulatory portfolio. And yet, it is the most legally significant — because it is the document where you, the manufacturer, formally declare under your own responsibility that your device meets every applicable requirement of the Medical Device Regulation.
Every medical device bearing the CE mark must have an EU Declaration of Conformity behind it. MDR Article 19 establishes this requirement, and Annex IV specifies exactly what the document must contain.
This post walks through every required element, explains common mistakes, and gives you a practical framework for getting it right.
What the Declaration of Conformity Is (and Is Not)
It is: A formal, legally binding statement by the manufacturer that a specific device conforms to the MDR.
It is not: A certificate from a Notified Body. The DoC is issued by you, the manufacturer. If a Notified Body was involved in the conformity assessment, their certificate is a separate document. The DoC references the NB involvement but stands on its own.
It is not: A marketing document. It is a regulatory document directed at market surveillance authorities and economic operators in the supply chain. It should be factual, precise, and complete.
It is not: A one-time document that you create and forget. The DoC must be kept up to date throughout the lifetime of the device. Changes to the device, changes to applicable standards, or changes to the Notified Body certificate can all trigger DoC updates.
The Required Content: Element by Element
MDR Annex IV specifies the information that must be included. Here is each element with practical guidance:
1. Manufacturer Name and Address
Your company's legal name and registered business address. If you have an authorized representative in the EU (required if you are established outside the EU), their name and address must also be included.
This must match exactly what is in EUDAMED and on your device labeling. Inconsistencies between documents create compliance questions that are easy to avoid.
2. The Statement That the DoC Is Issued Under the Sole Responsibility of the Manufacturer
This is the legal cornerstone. The standard phrasing is: "This declaration of conformity is issued under the sole responsibility of the manufacturer."
This is not boilerplate — it is the legal statement that makes the document binding. You are accepting full responsibility for the conformity of the device.
3. Product Identification — Name, Product or Trade Name, Product Code, Catalogue Number, or Other Unambiguous Reference
You must identify the specific device covered by the declaration. This identification must be unambiguous — someone reading the DoC must be able to determine exactly which product it covers.
Include: - Product name as it appears on the label - Model number or product code - Any trade name - Catalogue or reference numbers if applicable
For devices with multiple variants: The DoC should clearly identify all variants covered. You can use a single DoC for multiple variants of the same device if they share the same conformity assessment, or you can create separate DoCs. The key is unambiguous identification.
4. The UDI-DI (Unique Device Identification — Device Identifier)
MDR requires the Basic UDI-DI to be included on the Declaration of Conformity. The Basic UDI-DI is the primary identifier of a device model in EUDAMED and is different from the UDI-DI that appears on the device label.
5. Device Classification and Applicable Classification Rules
State the risk class of the device (Class I, IIa, IIb, or III) and reference the specific classification rule(s) from Annex VIII that you applied. For example: "Class IIa, classified under Rule 11 of Annex VIII."
This demonstrates that you have gone through the classification process and can trace your classification to specific rules. It also allows market surveillance authorities to quickly assess whether the conformity assessment route was appropriate for the class.
6. A Statement That the Device Is in Conformity with the MDR
The formal conformity statement. This declares that the identified device conforms to Regulation (EU) 2017/745.
If any Common Specifications apply and you have followed them, reference them here. If any Common Specifications apply and you have not followed them (choosing an alternative route to demonstrating conformity), you must state this and justify why.
7. Reference to Relevant Harmonized Standards Used
List all harmonized standards that you applied to demonstrate conformity. Include the standard number and edition. For example: - EN ISO 13485:2016 — Medical devices — Quality management systems - EN ISO 14971:2019 + A11:2021 — Application of risk management to medical devices - EN 62304:2006 + A1:2015 — Medical device software — Software life cycle processes
Only list standards you actually applied — not standards that exist in the general space of medical devices. Each listed standard must correspond to evidence in your technical documentation.
8. Reference to Other Standards or Technical Specifications Used
If you used standards or specifications that are not harmonized under MDR but that you relied on for demonstrating conformity, list them here.
9. Where Applicable, the Name, Address, and Identification Number of the Notified Body, the Conformity Assessment Procedure Performed, and Reference to the Certificate(s) Issued
If a Notified Body was involved in the conformity assessment (Class Is, Im, Ir, IIa, IIb, or III), this section must include: - The Notified Body's name and address - Their four-digit identification number - Which conformity assessment procedure was followed (reference to the specific Annex) - The certificate number(s) issued by the Notified Body
For self-certified Class I devices, this section is either omitted or marked as "Not applicable."
10. Additional Information Required by Other EU Legislation Applicable to the Device
If your device is also subject to other EU legislation (for example, the Radio Equipment Directive 2014/53/EU for devices with wireless communication, or Regulation (EU) 2016/425 for personal protective equipment), and you are declaring conformity with those regulations as well, reference them here.
11. Place and Date of Issue
The location and date when the DoC was issued. If you update the DoC, update this date to reflect the most recent version.
12. Name and Function of the Person Authorized to Sign
The name, title/function, and signature of the person authorized to sign on behalf of the manufacturer. This person must have the authority to bind the company legally.
In most startups, this is the CEO or managing director. The key requirement is that the signatory has actual authority — a quality manager may sign if they have been granted appropriate authority, but the authorization should be documented in your QMS.
Format and Presentation
MDR does not prescribe a specific format or template for the DoC. It can be a simple document — one or two pages. What matters is that all required elements are present, accurate, and clearly presented.
Practical formatting guidance:
- Use your company letterhead
- Number the document for version control
- Include a document revision history
- Use clear section headings that map to the Annex IV requirements
- Keep the language formal and precise — this is a legal document
- Provide it in the language(s) required by the Member State(s) where the device is made available
Language Requirements
MDR Article 19 requires the manufacturer to make the DoC available in the language(s) required by the Member State in which the device is made available or put into service.
In practice, this means: - If you sell in Germany, you need a German-language DoC (or one in a language accepted by Germany) - If you sell in France, you need a French-language DoC (or one in a language accepted by France) - If you sell across the EU, you may need multiple language versions
Many companies maintain a master DoC in English and prepare translations for specific markets. The translations must be accurate — the DoC is a legal document, and translation errors can create compliance issues.
Common Mistakes
Mistake 1: Listing Standards You Did Not Actually Apply
If you list EN 60601-1 on your DoC but your technical file does not contain an IEC 60601-1 test report, you have a problem. Every standard listed must correspond to actual evidence in your technical documentation.
Mistake 2: Wrong or Expired Notified Body Certificate Numbers
If the Notified Body has issued an updated certificate (replacing an expired one), your DoC must reference the current certificate number. Keeping expired certificate references on your DoC is a non-conformity.
Mistake 3: Inconsistent Device Identification
The device name, model number, and identifiers on the DoC must match exactly what appears on the device label, in EUDAMED, and in the Notified Body certificate. Inconsistencies — even minor ones like "Model A" on the label vs. "Model-A" on the DoC — create unnecessary compliance questions during audits and market surveillance inspections.
Mistake 4: Not Updating the DoC After Changes
The DoC is a living document. When you update your device, change standards, receive a new or revised NB certificate, or make any change that affects the information on the DoC, the DoC must be updated. Many startups create the DoC at initial CE marking and then forget about it.
Mistake 5: Signatory Without Authority
The person who signs the DoC must have documented authority to do so. If a quality manager signs but there is no documented delegation of authority in the QMS, market surveillance authorities may question the validity of the declaration.
Mistake 6: Missing the Basic UDI-DI
A common omission, especially for companies that treat UDI as a separate workstream from regulatory documentation. The Basic UDI-DI must be on the DoC.
The DoC in the Broader Regulatory Architecture
The Declaration of Conformity connects to several other regulatory deliverables:
Technical Documentation (Annex II): The technical file is the evidence base behind the DoC. Everything you declare on the DoC must be supported by evidence in the technical file.
CE Marking (Article 20): The CE mark on the device is the visible expression of the DoC. No DoC, no CE mark.
EUDAMED Registration: Your EUDAMED entry must be consistent with the DoC. The device identification, classification, and manufacturer information must match.
Notified Body Certificate: If applicable, the DoC references the NB certificate. The NB certificate and the DoC are complementary — the certificate confirms the NB's assessment; the DoC is the manufacturer's declaration.
Economic Operators in the Supply Chain: Importers and distributors may request a copy of the DoC. MDR Article 14 requires importers to verify that the manufacturer has drawn up a DoC before placing the device on the market.
How Long to Keep It
MDR Article 10(8) requires the manufacturer to keep the DoC (and the technical documentation) for at least 10 years after the last device covered by the declaration was placed on the market.
For startups, this means your document retention system must be capable of maintaining these records for a decade or more. Cloud-based document management systems handle this well, but ensure your retention policies explicitly cover regulatory documentation.
Practical Workflow for Startups
Here is a straightforward workflow for creating and maintaining your DoC:
- Create a DoC template in your QMS document control system
- Complete the template once all conformity assessment activities are finished
- Review the completed DoC against Annex IV requirements — check every element
- Cross-reference against your device label, technical documentation, EUDAMED entry, and NB certificate (if applicable) for consistency
- Authorize and sign by the person with documented authority
- Issue under document control — the DoC gets a document number, revision level, and effective date
- Distribute to economic operators in your supply chain as needed
- Review annually (at minimum) or whenever a triggering change occurs
- Archive superseded versions for the full retention period
The Bottom Line
The EU Declaration of Conformity is the document that connects everything — your technical documentation, your QMS, your Notified Body certification (if applicable), your EUDAMED registration, and your CE mark. It is short, simple, and critically important.
Get it right the first time. Keep it current. Keep it consistent with every other document and database entry. And treat the act of signing it with the seriousness it deserves — because when you sign the DoC, you are standing behind your device with your company's name, your reputation, and your legal accountability.