Declaration of Conformity

The Declaration of Conformity is an important legal document in which manufacturers declare the conformity of their medical devices. In this article you can read about the mistakes you absolutely have to avoid in order to make sure there are no legal consequences.

Phrasing the declaration of conformity “correctly”

Phrasing the declaration of conformity "correctly"

Advice from the ZLG

If you want to write a conformity assessment that complies with the regulations, then I’d recommend reading the ZLG EK-MED 3.9 A 4 document. You can even find a suggestion for the wording there, which you can largely adopt.

According to the ZLG, a Declaration of Conformity must contain:

  • The name and address of the manufacturer or its authorized representative
  • The EC directive(s) and their annex(es) according to which conformity is declared
  • The declaration that the manufacturer bears sole responsibility for the preparation of the Declaration of Conformity
  • Object of the declaration: Details of the medical device (name, type or model number)
  • Number of products the Declaration of Conformity refers to (e.g. lot, batch, serial numbers, quantities)
  • Additional details (e.g. standards, normative documents applied)
  • Place and date of issue of the Declaration of Conformity
  • Legally binding signature and function of the authorized person
  • Name, address and identification number(s) of the notified body/bodies involved in the conformity assessment procedures.

Tips from the Johner Institute

Naturally, my team and I are happy to:

  • Provide you with a template for a Declaration of Conformity (which, by the way, is part of Auditgarant)
  • Help you prepare a Declaration of Conformity
  • Or to check an existing one.

This means that you can be sure that this document also meets all the regulatory requirements. Don’t give your competitors an unnecessary chance to pester you with warnings.

Important tips for preparing a declaration of conformity

1st tip: Specify the responsibility for the declaration of conformity

There are far-reaching civil and criminal consequences of an unauthorized or incorrect conformity assessment. For this reason, you should define - for example, in a process instruction in your QM system - who is responsible for creating this important document and who is responsible for approving it. For small and medium-sized companies, this could be the manager.

2nd tip: Choose the right time to create the declaration of conformity

You must not declare conformity until you have gone through the conformity assessment procedure for the device. Depending on the class of the medical device, this may require an EC certificate from the notified body.

But you must have declared conformity before affixing the CE mark to your device.

3rd tip: Define the device precisely

A declaration of conformity must refer precisely to an identifiable device or device type. This identifiability is usually achieved through:

  • The name of the medical device and
  • The product code
  • Or another reference.

A declaration of conformity for a medical device class is not permitted.

4th tip: Keep the declaration of conformity ready

As the manufacturer, you must have the conformity assessment at hand as part of the technical documentation for the device and you must be able to submit it at any time on request. A lot of manufacturers even publish them on their websites.

5th tip: Don’t declare conformity “indefinitely”

A wording that does not contain any limit in terms of the period of validity does not meet the regulatory requirements, such as those of the ZLG.

You can limit the validity, for example:

  • To a defined period of time (e.g. for 2 years from the sale of the first device)
  • Up to a defined point in time
  • To a certain number of devices
  • To a batch number
  • Up to the time the EC certificate is no longer valid.

6th tip: Don’t reference any standards

Make sure that you do not refer to "whole" standards in the Declaration of Conformity, because if you do you’ll have to comply with the whole standard, even if parts of it don’t apply to you at all.

In addition, you would have to amend the Declaration of Conformity every time a standard changes.


Prof. Dr. Christian Johner


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