On 20 April 2026, the Medical Device Coordination Group published MDCG 2021-24 Rev.1, the first revision of its guidance on the classification of medical devices under EU
MDR 2017/745 since the original document was released in October 2021. This guidance presents relevant clarifications on classification rule interpretation that
may impact classification rationales, technical documentation and conformity assessment activities. For manufacturers with devices falling under Rules 8, 9, 10, 12,
16 or 22, this update should already be under their radar.
In this article, Alberto Bardají, Head of Medical Devices at MDx CRO, with 20 years of experience in the field, and a former Notified Body expert, walks through what changed, what it means in practice, and what manufacturers should check in their existing documentation.
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What Is MDCG 2021-24 and Why Does It Matter?
MDCG 2021-24 is the primary guidance document for applying the 22 classification rules set out in Annex VIII of EU MDR 2017/745. It provides definitions, practical interpretation notes, decision flowcharts and worked examples for each rule.
Classification under the MDR determines which conformity assessment route the manufacturer must follow, the level of clinical evidence required and the extent of scrutiny by the Notified Body. A change in classs can have substantial consequences for the certification timeline, cost, and the content of the technical file.
Although MDCG guidance documents are not legally binding, they reflect how the Medical Device Coordination Group, as established in Article 113 and with representatives from all Member States, interprets the MDR in practice. They become the reference point during application reviews and borderline classification assessments.
Why This Revision? The Background
Updates to MDCG guidance documents are not uncommon and are typically driven by practical experience gathered after the previous version entered into use.
According to Alberto Bardají, “the revision was likely driven by feedback collected from different stakeholders and working groups, based on the experience accumulated since the 2021 version. Over the last years, situations have emerged where certain classification concepts were interpreted inconsistently, or where the wording of the guidance left room for different interpretations. This revision addresses a number of those situations.”
Rev.1 was also published on the same day as Version 5 of the Borderline and Classification Manual, the mechanism through which EU Member States submit borderline product cases for multilateral review. Together, these updates provide two useful tools for supporting classification decisions in challenging or borderline cases.
What Changed in MDCG 2021-24 Rev.1
The revision introduces several updates across the guidance, particularly in relation to implantable devices, spinal fixation systems and selected active devices.
Implantable Devices (Section 3.1.4)
A new clarification has been introduced stating that:
“The term clinical procedure will encompass both surgical and non-surgical procedures.”
This expands the interpretation of clinical procedures associated with implantable devices and may be relevant when assessing classification rationales involving non-surgical implantation techniques.
Spinal Fixation Systems (Rule 8)
One of the most notable updates concerns spinal implant systems.
A new note clarifies that hooks intended to fix rods onto the spinal column should be considered similar to screws, wedges, plates and instruments under the exemption contained in Rule 8.
In addition, the guidance now provides further clarification regarding what constitutes contact with the spinal column.
These changes improve consistency in the classification of spinal fixation systems and provide additional clarity for manufacturers developing new spinal implant technologies.
Article 52(4) Clarification
The revised guidance also clarifies that the list of devices referenced in Article 52(4) should not be interpreted as having classification intent.
Classification remains subject to Annex VIII, while Article 52(4) addresses conformity assessment provisions applicable to certain Class IIb implantable devices.
This clarification is particularly relevant because the exemption list includes device types that may, depending on their intended purpose, be classified in classes other than Class IIb.
Terminology Update (Section 3.2)
The guidance now replaces the term device with product in the section describing the application of classification rules.
While the guidance does not explicitly explain the rationale for this change, it appears consistent with the broader scope of the MDR, including certain Annex XVI products without an intended medical purpose.
Although this update does not affect the classification rules themselves, it reflects a wider applicability of the guidance beyond traditional medical devices.
Active Devices (Rules 9 and 10)
The decision diagram for Rule 9 has been reorganised to better align with the wording and structure of the rule.
Examples previously referenced within Rule 9 have also been incorporated directly into Rule 10, including:
- Surgical lamps (Class I)
- Devices for visual electrophysiology (Class IIa)
- Fundoscopes for examination of the eye (Class IIa)
In addition, the wording “but may include diagnosis” has been removed from Note 1 of Rule 10.
While these changes do not alter the underlying classification logic, they improve readability and consistency within the guidance.
Pressure Regulators for Medical Gases (Rule 12)
The Class IIb example has been refined from “pressure regulators for medical gases” to “pressure regulators for medical gases with integrated flow meter”.
Sterilizers (Rule 16)
The sterilizer example has been updated to explicitly refer to sterilizers intended for invasive or non-invasive medical devices.
Defibrillators, Pads and Electrodes (Rule 22)
The existing example relating to automated external defibrillators (AEDs) has been refined by clarifying that pads and electrodes are included only where they form an integral part of the defibrillator.
A new Note 2 further explains that pads and electrodes placed on the market separately may be classified under Rule 9 or Rule 1, depending on their intended purpose and characteristics.
What Should Manufacturers Do?
Manufacturers should review existing classification rationales to determine whether any of the updated clarifications, notes or examples are relevant to their devices.
Particular attention should be given to implantable devices, spinal fixation systems and active devices, where the most significant updates have been introduced.
Frequently Asked Questions
No. MDCG guidance documents are not legally binding and cannot be regarded as the official position of the European Commission. Only the Court of Justice of the EU can give binding interpretations. However, in practice, MDCG guidance documents are the primary reference used by Notified Bodies and competent authorities during conformity assessment reviews.
Referencing the 2021 version is not in itself a compliance issue. The question is whether the classification conclusions in your technical file remain valid under Rev.1. If they do, document a brief review confirming that conclusion and referencing the new version. If they do not, engage your Notified Body proactively.
Rule 8 carries the most substantive changes for most manufacturers, particularly those with implantable devices, spinal implants, AIMD accessories, or devices relying on the Article 52(4) exemption. Manufacturers of active diagnostic and monitoring devices (Rule 10) and infusion-related active devices (Rule 12) should also compare their classification rationale against the updated tables.
Likely starting from the date of publication. MDCG 2021-24 rev.1 is already the reference document for classification and borderline cases. If the clarifications in the new guidelines impact your existing classification rationale, a remediation plan should be agreed with your Notified Body.
Key Takeaways
- MDCG 2021-24 Rev.1 updates classification guidance for Rules 8, 9, 10, 12, 16 and 22 under EU MDR 2017/745.
- The replacement of ‘surgical’ with ‘clinical’ in the implantable device definition is the most consequential single change, closing a longstanding classification argument for minimally invasive placements.
- Rule 8 receives seven new practical notes, with Notes 1 (Article 52(4)), 6 (AIMD accessories), and 7 (spinal column contact) most likely to generate Notified Body questions.
- Rev.1 was published alongside Borderline and Classification Manual v5, both should be reviewed together.
- Notified Bodies are applying this guidance now. Manufacturers should not wait for a surveillance audit to review their classification rationale.
- Where the new guidance does not affect your classification conclusion, document that review. Where it does, engage your Notified Body proactively.
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