Regulatory background: well-established technologies and Article 61 MDR

Under Regulation (EU) 2017/745 (MDR), implantable devices and class III devices are subject to rigorous clinical evidence requirements. As a general rule, manufacturers must conduct clinical investigations to generate the clinical data required to demonstrate conformity with the applicable general safety and performance requirements (GSPR) set out in Annex I MDR.

Article 61(4) MDR establishes a limited exception: where it is duly justified — on the basis of sufficient clinical data from the equivalent device or from clinical evaluations of devices already on the market — clinical investigations may not be required. Article 61(6)(b) MDR codifies a further, specific exception for a defined list of device types qualifying as well-established technologies (WET), which by virtue of their common and stable design, well-known safety and clinical performance, and long market history, are exempted from the clinical investigation obligation.

Article 61(8) MDR expressly empowers the European Commission to amend this list by delegated act, drawing on experience gained in the application of the MDR and following consultation with the Medical Device Coordination Group (MDCG). The delegated regulation of 20 March 2026 exercises precisely this power — and its scope is considerably broader than many manufacturers may have anticipated.

From a Pure Clinical perspective, this delegated act is one of the most practically significant regulatory developments of 2026. The WET exemption has been underutilised, partly due to the narrowness of the original list, and partly due to uncertainty about how notified bodies would apply it in practice. This expansion changes the calculus materially for a substantial number of device manufacturers.

What the updated regulation introduces

The delegated regulation replaces Article 61(6)(b) MDR in its entirety, substituting the previous exemption list with an expanded and restructured catalogue organised across two device groupings. The updated list now encompasses:

  • Group (a): sutures, staples, dental fillings, dental braces, tooth crowns, screws, wedges, plates, wires, pins, clips and connectors — device types already present in the original list, retained without modification.
  • Group (b): a substantially enlarged list of implantable and class III devices, including — among others — cranial perforators, catheter passers, magnets for implantable pulse generators, port catheters, ventricular drains, feeding tubes, bone tacks, bone wax, bone fillers, bone substitutes, stem centralisers, dental implants, orthodontic devices, spinal posterior fixations, guidewires, pressure wires, pacing wires and leads, endovascular embolisation coils, embolisation particles, shunts, cables and internal defibrillation paddles. [Art. 1, C(2026) 1798 final]

The Explanatory Memorandum confirms that the newly added device types were identified through a wide stakeholder consultation conducted in 2025, involving observers to the MDCG Clinical Investigation and Evaluation Performance Studies Working Group and the Borderline and Classification Working Group. Each device category added to the list was assessed against the established WET criteria set out in MDCG 2020-6: common and simple design, demonstrated stability, well-known safety profile, absence of associated safety issues, and long market history within the EU. [Recital 2, C(2026) 1798 final]

One critical clarification, which carries significant operational implications, is embedded in Recital 5: even where manufacturers are exempted from conducting clinical investigations, they remain fully required to plan, conduct and document a clinical evaluation in accordance with Article 61 MDR. The exemption eliminates the investigation obligation; it does not reduce the clinical evaluation obligation. This distinction must be clearly understood by regulatory affairs and clinical affairs teams when updating clinical evaluation reports (CERs) for affected devices.

Conditions for reliance on the WET exemption

Eligibility for the Article 61(6)(b) exemption is not automatic upon device type inclusion in the list. The regulation establishes a conditional structure: the exemption applies only where the clinical evaluation is based on sufficient clinical data and is in compliance with the relevant product-specific common specification (CS), where such a CS exists. [Art. 1, C(2026) 1798 final]

In practical terms, manufacturers seeking to rely on the updated exemption must demonstrate:

  • that the device falls within the scope of one of the listed device type categories as defined in the amended Article 61(6)(b) MDR,
  • that the clinical evaluation is grounded in sufficient existing clinical data — including post-market surveillance data, literature, and real-world evidence where available,
  • compliance with any applicable product-specific common specification (CS) issued pursuant to Article 9 MDR, which may set minimum clinical data requirements for specific device types,
  • full compliance with the clinical evaluation methodology requirements of Article 61 MDR and Annex XIV MDR, including systematic literature review, appraisal and analysis of clinical data, and a clearly documented benefit-risk assessment.

From a Pure Clinical standpoint, the CS conditionality is a critical control point that manufacturers must not overlook. Where a CS exists for a device type now listed in Article 61(6)(b), it effectively defines the minimum clinical data floor that must be met before the exemption is invocable. Manufacturers who assume that list inclusion alone grants exemption without satisfying CS requirements do so at significant regulatory risk.

Implications for clinical evaluation strategies

The expansion of the WET exemption list creates both an opportunity and an obligation for manufacturers of the newly listed device types. The opportunity lies in the potential to avoid the significant time, cost, and resource burden associated with prospective clinical investigations. The obligation lies in the requirement to rigorously establish that all applicable conditions are met — and to maintain that demonstration through the device lifecycle.

Key clinical evaluation implications include:

  • CER update requirement: manufacturers of devices now eligible for the WET exemption should assess whether existing CERs adequately reflect this pathway or require revision to explicitly invoke the Article 61(6)(b) exemption and document the basis for its application.
  • Sufficiency of clinical data: the exemption shifts the evidentiary focus from clinical investigation data to existing clinical data quality and completeness. Post-market clinical follow-up (PMCF), systematic literature review, and post-market surveillance (PMS) outputs become the primary evidence inputs.
  • Equivalence claims: for devices where the clinical evaluation has historically relied on equivalence to a predicate, manufacturers should assess whether the WET pathway now offers a more robust and defensible basis — particularly given the continued scrutiny notified bodies apply to equivalence claims for class III and implantable devices.
  • Devices not included in the expanded list: for implantable and class III device types that remain outside the WET exemption, the clinical investigation obligation under Article 61 MDR remains unchanged. The risk of misclassifying a device as WET-eligible without adequate justification is one that notified bodies will scrutinise closely.

In our experience, the most consequential risk in applying the WET exemption is the assumption that list membership substitutes for clinical evaluation rigour. It does not. Notified bodies are fully expected to assess whether the clinical evaluation documentation for WET-exempt devices is scientifically robust, Annex XIV-compliant, and commensurate with the risk profile of the specific device — not merely its device type category.

Notified body scrutiny and audit expectations

Even where the WET exemption applies, manufacturers should not underestimate the level of scrutiny that notified bodies will apply to clinical evaluation documentation during technical file review and periodic audit cycles.

Based on current regulatory practice, notified body review of WET-exempt device files is expected to include:

  • verification that the device type falls clearly and unambiguously within the scope of the amended Article 61(6)(b) device list,
  • assessment of whether the clinical data supporting the CER is sufficient in scope, quality, and recency — with particular attention to the post-market surveillance data cycle and PMCF output,
  • confirmation that any applicable common specification (CS) requirements have been fully addressed and documented in the CER,
  • evaluation of the benefit-risk justification as required under Annex XIV, Part A, MDR — including the adequacy of residual risk mitigation and the absence of safety signals that would undermine the WET determination,
  • scrutiny of the PMCF plan to confirm that ongoing post-market clinical evidence generation is appropriately structured for the device and its intended purpose.

A practical consequence of this scrutiny landscape is that manufacturers must treat the WET exemption not as a reduction of clinical diligence, but as a redirection of it — from prospective investigation design toward comprehensive post-market evidence management and CER maintenance.

Entry into force and transition considerations

The regulation enters into force on the twentieth day following its publication in the Official Journal of the European Union. [Art. 2, C(2026) 1798 final] As of the date of this article, the Official Journal publication timeline has not yet been confirmed, but manufacturers should treat the regulatory direction as settled and initiate internal impact assessments without delay.

Key transition actions for manufacturers include:

  • device portfolio review: identify all implantable and class III devices that may now fall within the expanded Article 61(6)(b) list and assess whether conditions for exemption are currently met,
  • CER gap analysis: for potentially WET-eligible devices, assess whether the existing CER structure, clinical data sources, and benefit-risk documentation are sufficient to support the WET pathway, or whether targeted updates are needed,
  • notified body communication: where applicable, initiate dialogue with the responsible notified body regarding the impact of the delegated regulation on scheduled recertification or surveillance audits,
  • SOP and process update: ensure internal clinical evaluation procedures, templates, and PMCF planning documents are updated to reflect the amended Article 61(6)(b) scope,
  • regulatory timeline reassessment: for devices where the WET exemption removes a planned clinical investigation from the conformity assessment pathway, reassess regulatory timelines and budget projections accordingly.

Toward a more proportionate clinical evidence framework for established devices

The Commission Delegated Regulation C(2026) 1798 final represents a meaningful step toward a more proportionate regulatory framework for devices with long, well-documented EU market histories. By expanding the WET exemption list, the Commission acknowledges that the clinical investigation requirement — however justified for novel and higher-risk technologies — should not impose disproportionate burden on device types whose safety and clinical performance are well characterised and uncontested.

For manufacturers, the message is clear: this is an opportunity to streamline conformity assessment pathways for qualifying devices, but only where the underlying clinical evaluation framework is rigorous, well-documented, and lifecycle-compliant. Regulators and notified bodies will not accept the WET exemption as a justification for reduced clinical oversight — they will use it as a lens through which to assess whether the existing clinical evidence base is genuinely sufficient.

Organisations that invest in building robust, Annex XIV-compliant clinical evaluation documentation now will be best positioned to benefit from the flexibility the updated regulation provides — while avoiding the compliance risk that comes with treating exemption as a shortcut rather than a structured, evidence-based pathway.

Key references

[1] Commission Delegated Regulation (EU) C(2026) 1798 final — Amending Regulation (EU) 2017/745 as regards the list of implantable devices and class III devices exempted from the obligation to perform clinical investigations (20 March 2026)