What the EU MDR’s Expanded Well-Established Technology Scope Means for Manufacturers

Expanded EU MDR Scope for Well-Established Technology (WET)

The European Commission’s adoption of Delegated Regulations (EU) 2026/1359 and (EU) 2026/1451 marks an important evolution in the implementation of the Medical Device Regulation (MDR). By expanding the range of medical devices considered to have characteristics of Well-Established Technology (WET), the Commission has taken a more proportionate approach to regulating technologies with long histories of safe and effective clinical use.  

Manufacturers can now reassess both their regulatory and clinical strategies in light of these changes. 

Historically, the MDR recognised only a relatively limited list of devices as having established safety and performance profiles. 

The new Delegated Regulations significantly expand these lists. Under Article 52(4), additional implantable Class IIb devices qualify for available regulatory flexibility. Under Article 61(6)(b), the expanded scope now includes additional implantable and Class III devices. The rationale is clear: these technologies share common and stable designs, well-understood risk profiles, established clinical performance, and decades of clinical experience supporting their use.  

While the headlines may focus on regulatory relief, the real significance lies in the European Commission’s recognition that a more risk-based and evidence-driven approach can be applied to technologies whose clinical characteristics are already well understood.  

EU MDR Articles 52(4) and 61(6)(b): Key Differences

One of the most important points for manufacturers is that the two Delegated Regulations address different aspects of MDR compliance and should be considered independently.  

Under Article 52(4), the changes relate to conformity assessment pathways for certain Class IIb implantable devices. For eligible devices, manufacturers will have greater flexibility in how conformity assessment activities are conducted, potentially reducing the need for extensive technical documentation assessments for every individual device and allowing greater reliance on quality management system oversight.  

By contrast, the expansion under Article 61(6)(b) relates to clinical evidence requirements. It allows manufacturers to demonstrate conformity for a broader range of implantable and Class III devices without conducting new clinical investigations, provided sufficient clinical evidence can be demonstrated through existing data sources. Manufacturers may draw on scientific literature, clinical experience, data on equivalent devices, and post-market information to support conformity.  

This distinction is important because it is easy to interpret these changes as exemptions from clinical evidence requirements. They are not. 

The MDR continues to place responsibility on manufacturers to demonstrate that their devices are safe, perform as intended, and maintain a positive benefit-risk profile. The requirement for robust clinical evaluation has not changed. What has changed is the recognition that, for certain well-established technologies, manufacturers may answer clinical questions using existing evidence rather than generating additional data through new clinical investigations. 

How the Expanded WET Scope Affects Manufacturers

For many manufacturers, the most immediate impact of these Delegated Regulations may not be related to clinical investigations, but rather to regulatory strategy and conformity assessment planning. 

Article 52(4) expands the range of eligible device types and gives manufacturers new opportunities for certain Class IIb implantable devices to utilise alternative conformity assessment pathways. Depending on their portfolio, manufacturers may assess technical documentation differently, maintain certificates more efficiently, and manage changes in a different way throughout the certification lifecycle.  

As a result, manufacturers should carefully evaluate not only whether their devices fall within the expanded WET scope, but also the potential impact of their chosen route to conformity on the overall assessment burden. Some organisations, may improve efficiency by leveraging a quality management system certification approach may provide efficiencies in the management of product portfolios, change control activities, and the introduction of new devices within an existing certification scope. However, the benefits will vary significantly depending on the manufacturer’s specific device portfolio, certification structure, and long-term regulatory strategy. Manufacturers should clearly justify and document any use of WET exemptions within the technical documentation. 

The changes associated with Article 61(6)(b) create a separate opportunity to reassess clinical evidence strategies. While certain devices may no longer require new clinical investigations where sufficient clinical evidence already exists, manufacturers remain responsible for demonstrating that the available evidence adequately supports safety, performance, and benefit-risk conclusions. Clinical investigations may still be necessary where evidence gaps remain.  

However, there are also important questions that remain unanswered. 

In publication The MDR/IVDR Revision: Impact on Clinical Evaluations and Clinical Investigations, we highlighted several concerns associated with the proposed expansion of devices listed as Well-Established Technology (WET). One of the most significant challenges is the absence of detailed guidance or strict definitions describing what devices are intended to fall within some of the newly introduced generic device categories. 

As a result, manufacturers, consultants, and Notified Bodies may not always interpret eligibility for the associated regulatory flexibilities in the same way. This may lead to questions regarding whether a specific design variation, material technology, intended purpose, or product configuration falls within the relevant WET classification (listed device and paragraph 2 description). 

This lack of detailed guidance makes robust regulatory justification and early engagement even more important. Manufacturers should avoid assuming that inclusion of a generic device type automatically guarantees eligibility for a particular conformity assessment route or clinical evidence approach. Manufacturers should assess each device based on its own characteristics, risk profile, intended purpose, classification, available evidence and level of novelty. Manufacturers should then use that assessment as a basis to develop and document a clear justification for adopting the exemption.  

Given the potential for varying interpretations, manufacturers should consider engaging early with their Notified Body to discuss the proposed route to conformity, clinical evidence strategy, and the potential impact on assessment burden. Early structured dialogue can help identify areas requiring additional justification, support alignment of expectations, and ultimately contribute to a more predictable conformity assessment process.

WET Eligibility Under the MDR: How Novelty Affects Qualification

While the Delegated Regulations add additional exempted devices to both Articles 52 and 61, it is important to note that Paragraph 2 of these acts further clarifies the characteristics expected of the devices included. Specifically, the Delegated Regulations describe devices that “have a common, simple, and stable design; they have well-known safety and they have not been associated with safety issues in the past; they have well-known clinical performance characteristics and they are standard of care devices with little evolution in indications and the state of the art; and they have a long history on the Union market”. 

The Commission’s wording suggests that devices incorporating novel features that could affect clinical performance, whether through technological innovation or changes in intended purpose, may not meet the criteria of a “well-established technology” (WET). Such devices may not qualify for the reduced level of regulatory scrutiny afforded to WET devices. 

It is important to emphasise that novelty, in this context, refers to characteristics that deviate from those of a well-known and established technology. It does not simply mean that a device is newly introduced to the market. Regulators may still consider a new device that is substantially similar to an established technology to be a WET device. Therefore, the concept should not be interpreted as applying only to legacy devices.

EU MDR Requirements That Remain Unchanged

Although the new Delegated Regulations provide additional flexibility, all other core MDR obligations remain unchanged. Manufacturers should be careful not to assume that WET status affects other regulatory requirements.  

The Delegated Regulations do not alter requirements related to: 

• Confirmation of conformity with relevant general safety and performance based on sufficient clinical evidence 
• Post-Market Clinical Follow-up (PMCF) 
• Periodic Safety Update Reports (PSURs) 
• Summary of Safety and Clinical Performance (SSCP) 
• Clinical Evaluation Consultation Procedures (CECP) 
• Article 18 (Implant Cards) as exempt devices have not changed 

Manufacturers must continue to maintain robust post-market surveillance systems and collect and evaluate clinical data throughout the product lifecycle. 

What the New MDR WET Rules Mean for Manufacturers

As regulators gain experience implementing the MDR, they increasingly recognise that regulatory requirements should be proportionate to the level of uncertainty associated with a medical device. It is reasonable to allow manufacturers greater flexibility in how compliance is demonstrated while maintaining high standards for patient safety.  

The next step for manufacturers is clear: review device portfolios against the expanded scope, reassess clinical evidence strategies, and evaluate whether current conformity assessment pathways remain the most appropriate and efficient. Companies that act now will be best positioned to capitalise on the opportunities presented by these changes while continuing to meet MDR expectations. Manufacturers should ensure that any adoption of WET exemptions are well-documented and justified. 

Ultimately, these Delegated Regulations represent a welcome move toward a more proportionate regulatory framework. Manufacturers should apply these changes thoughtfully, ensuring that regulatory efficiencies are realised without compromising the robust evidence base that remains the foundation of patient safety and device performance. 

Disclaimer. The views and opinions expressed in this article are solely those of the author and do not necessarily reflect the official policy or position of Test Labs Limited. The content provided is for informational purposes only and is not intended to constitute legal or professional advice. Test Labs assumes no responsibility for any errors or omissions in the content of this article, nor for any actions taken in reliance thereon.