For twenty years, Directive 93/42/EEC organised access to the European market for medical devices. Regulation (EU) 2017/745, which became applicable on 26 May 2021, is not a revision of that directive. It is a change of logic.
Many manufacturers discovered the scale of this change too late, when trying to transpose their directive files into the MDR format. The result: missed deadlines, cascading requests for additional information, and market launches delayed by several years.
Here is what really changed, what did not change, and how much time is left for those still holding directive certificates.
Clinical demonstration: from presumption to proof
Under the directive, demonstrating clinical equivalence with an existing device was sufficient in the vast majority of cases. The criteria were barely formalised, and a manufacturer could rely on a competitor’s data without access to its documentation.
The MDR restructures this demonstration. Article 61 requires a documented clinical evaluation, updated throughout the life cycle. Equivalence remains possible, but its criteria are precise and cumulative: technical, biological and clinical equivalence, detailed by guidance MDCG 2020-5.
One point deserves to be put back in its proper place: the requirement for a contract granting full and permanent access to the third-party manufacturer’s technical documentation applies only to implantable and class III devices (Article 61(5)). For those devices, equivalence with a competing product has become theoretical: no competitor signs such a contract. For a non-implantable class IIa or IIb device, on the other hand, equivalence remains a workable route, provided it is documented against the three criteria and the level of data access is justified. Some SMEs launched costly clinical investigations believing equivalence was dead for everyone. It is only dead where the regulation locked it down.
Post-market surveillance: from formality to operational obligation
Under the directive, post-market follow-up existed on paper. Many manufacturers were content with a complaint-handling procedure and a minimal annual review.
The MDR imposes a structured system in Articles 83 to 86. The surveillance plan describes the data collection strategy. The periodic synthesis takes two forms depending on the class: a post-market surveillance report for class I (Article 85), a PSUR for class IIa and above (Article 86). The PMCF plan specifies how the manufacturer continues to collect clinical data after placing the device on the market. These documents must exist, be consistent with one another, and stay alive.
A class IIa PSUR is updated at least every two years. For class IIb and III, every year. It is no longer a one-off exercise, it is a cycle. Surveillance also has its reactive side: the vigilance obligations and their deadlines frame the reporting of serious incidents.
Classification: 22 rules, and targeted up-classifications
Annex VIII of the MDR contains 22 classification rules, against 18 under the directive. Several pushed entire families of devices up a class.
Rule 11 and the classification of software is the most visible illustration: software that provides information used for diagnostic or therapeutic decisions is class IIa at a minimum, and rises to IIb or III depending on the severity of the consequences of an error. Software self-certified as class I under the directive found itself in IIb, with everything that implies: notified body, complete technical file, substantial clinical evaluation.
Another change, often confused with a reclassification: reusable surgical instruments remain class I, but under the sub-class Ir, with notified body involvement limited to the reuse aspects. The manufacturer who fully self-certified under the directive no longer self-certifies alone. Some implants have, moreover, genuinely changed class, such as spinal-contact implants moved up to class III (rule 8).
Traceability: UDI and EUDAMED
The directive provided for no centralised identification system. The MDR imposes the UDI (Article 27) and the EUDAMED database (Article 33). Each device carries a unique identifier, linked to registered technical and regulatory data, for traceability from manufacture through to the patient.
Since 28 May 2026, use of the first four EUDAMED modules is mandatory, including actor registration and the UDI/devices module. For a non-EU manufacturer, registration as an actor and obtaining the SRN number go through the verification of its information by its European authorised representative. Device registration then remains an obligation of the manufacturer itself. The relationship with the authorised representative is therefore structured from entry into the system, not at the first incident. To go further: the UDI system and EUDAMED registration, and the role of the EU authorised representative in EUDAMED for non-EU manufacturers.
What has not changed
The basic mechanics of CE marking remain identical: the manufacturer demonstrates compliance with the requirements, the notified body assesses and certifies where required, and the CE marking is affixed. Primary responsibility remains with the manufacturer, even when design or manufacturing activities are subcontracted.
Article 120: how much time directive certificates have left
Part of the market still lives under the directive. The transitional regime of Article 120, extended by Regulation (EU) 2023/607, allows devices under directive certificates to be kept on the market, with deadlines that depend on the class: 31 December 2027 for class III devices and class IIb implantables, 31 December 2028 for other class IIb devices, class IIa and classes Is, Im and Ir.
This reprieve was conditional, and the conditions are now behind us: a QMS compliant with the MDR and a formal application filed with a notified body by 26 May 2024, then a written agreement signed with that body by 26 September 2024. A manufacturer that meets these conditions is now running through its certification. A manufacturer that does not is no longer in transition: its devices no longer have a legal basis for being placed on the market.
For those in the clear, the 2027 or 2028 deadline is not the date to remember. The date that matters is that of the MDR certificate, and it depends on the notified body’s queue and the maturity of the file. A class IIb file entering assessment in 2026 for a deadline at the end of 2028 has no margin for an immature clinical evaluation report. Better to select your notified body and learn the real timelines before building your schedule.
What it means for a micro-enterprise/SME
The MDR transition increased the regulatory burden in a lasting way. On the files we see come through, a class IIa technical file under the MDR represents two to three times the volume of an equivalent directive file. And maintaining compliance is continuous: a file validated yesterday may no longer be compliant tomorrow if new surveillance data alter the benefit/risk ratio.
This burden is predictable and can be planned for. Manufacturers who built their MDR files before their directive certificates expired avoided critical delays. The others suffered. In 2026, the question is no longer to anticipate the transition, it is to know exactly where yours stands: Article 120 conditions met or not, position in the notified body’s queue, weak areas of the file. Those three answers fit on one page, and that page changes what comes next. The simplest route is to take stock of your MDR transition.
Regulatory source: Regulation (EU) 2017/745 consolidated — EUR-Lex and Regulation (EU) 2023/607. Guidance MDCG 2020-5, health.ec.europa.eu.