EU Reference Laboratories (EURLs) for IVDR Class D IVDs: Performance Verification, Batch Testing, and Manufacturer Preparation Guide

Why EU Reference Laboratories Matter for Class D IVD Manufacturers

If you manufacture a Class D in vitro diagnostic under the EU IVDR, a new layer of regulatory scrutiny has been operational since October 2024 and is now expanding. EU Reference Laboratories (EURLs) have been performing independent performance verification and batch testing for four categories of Class D devices since October 1, 2024. As of May 1, 2026, two additional categories -- parasite infection markers and blood grouping markers -- have been brought into the EURL framework. This is not theoretical. The designating legislation has been published, the EURLs have been identified, and Notified Bodies have been working with them for months.

For manufacturers of Class D IVDs in affected device categories, this changes the conformity assessment timeline and the documentation expectations. For manufacturers outside the currently designated categories, it signals the direction of travel: the European Commission has the authority to expand EURL coverage to additional Class D device types over time. Every Class D IVD manufacturer needs to understand how this system works.

This guide covers the legal basis for EURLs, which device categories are currently affected, how performance verification and batch testing work in practice, what the Notified Body's role is, what manufacturers must prepare, and what the implications are for conformity assessment timelines going forward.

What Are EU Reference Laboratories (EURLs)?

Legal Basis: IVDR Article 100

Article 100 of the In Vitro Diagnostic Regulation (EU) 2017/746 gives the European Commission the authority to designate EU Reference Laboratories for high-risk in vitro diagnostics. These are independent laboratories that perform specific tasks related to the verification of device performance during the conformity assessment of Class D IVDs.

The concept is not new in EU regulatory frameworks. EU Reference Laboratories already exist in other regulated sectors. What is new is their application to IVDs. Under the old IVDD, there was no independent laboratory verification step in the conformity assessment process, even for the highest-risk devices. The IVDR introduced this requirement to add a layer of scientific scrutiny that goes beyond what a Notified Body can assess through documentation review alone.

Why EURLs Were Introduced

Class D IVDs are the highest risk category under the IVDR. These are devices used for detecting transmissible agents in blood, organs, tissues, and cells — devices where an incorrect result can have life-threatening consequences for individual patients and significant public health implications. HIV screening assays, hepatitis detection tests, blood grouping reagents, and respiratory pathogen panels used in pandemic response all fall into this category.

Under the IVDD, conformity assessment for even these highest-risk devices relied on Notified Body review of the manufacturer's technical documentation. There was no systematic, independent laboratory testing to verify that the device actually performed as claimed. The IVDR's drafters concluded that for devices of this risk level, documentation review alone was insufficient. Independent laboratory verification would provide an additional safeguard — a direct, empirical check that the device works as the manufacturer says it does.

The Regulatory Framework

Two pieces of legislation establish the EURL system:

1. Commission Implementing Regulation (EU) 2023/2713: Published in 2023, this regulation designated the first EURLs for specific Class D device categories and set out the tasks they would perform.

2. Commission Implementing Regulation (EU) 2025/2526: Published on December 16, 2025, this regulation amended (EU) 2023/2713 to designate additional EURLs for parasite infection markers and blood grouping markers, with a date of application of May 1, 2026. It also corrected the designation of an existing consortium.

The original four categories became subject to EURL verification from October 1, 2024. The two additional categories (parasite infection and blood grouping markers) became subject to EURL verification from May 1, 2026. After each respective date, Class D devices in the applicable designated categories that are submitted for conformity assessment undergo EURL verification as part of the process.

Currently Designated EURL Categories

The Six Device Categories

EURLs have been designated for six categories of Class D devices. The first four became operational on October 1, 2024; the remaining two became operational on May 1, 2026:

What These Categories Cover

Each category encompasses Class D devices intended for the detection, identification, or quantification of the relevant infectious agent or marker. The specific devices affected include:

• Hepatitis or retrovirus infection markers: Devices for detecting hepatitis A, B, C, D, and E viruses, as well as HIV-1, HIV-2, and HTLV. This includes screening assays used in blood banking, confirmatory tests, and viral load monitoring assays classified as Class D.

• Herpes virus infection markers: Devices for detecting herpes simplex virus (HSV), cytomegalovirus (CMV), Epstein-Barr virus (EBV), varicella-zoster virus (VZV), and human herpesvirus types 6, 7, and 8 where the intended purpose places them in Class D.

• Bacterial agents: Devices for detecting bacterial pathogens classified as Class D under Rule 1 of Annex VIII — typically agents that pose a high risk of transmission through blood or tissue donation, or agents with serious public health consequences.

• Respiratory virus markers: Devices for detecting respiratory viruses with pandemic potential or serious public health impact — influenza, SARS-CoV-2, RSV, and other respiratory pathogens classified as Class D.

• Parasite infection markers: Devices for detecting parasitic infections such as malaria, Chagas disease, and toxoplasmosis where the intended purpose relates to screening blood, tissue, or organ donations.

• Blood grouping markers: Devices used for ABO, Rh, Kell, and other blood group typing — reagents, test systems, and ancillary materials used in transfusion medicine and donor screening.

What Is Not Currently Covered

Class D devices that fall outside these six categories are not subject to EURL verification as of May 2026. This means that Class D devices for detecting other transmissible agents — for example, certain prion diseases, emerging pathogens not yet categorized, or other infectious agents that fall under Rule 1 but are not within the six designated categories — will continue to be assessed by the Notified Body through alternative means.

However, the European Commission retains the authority to expand EURL coverage to additional categories over time. Manufacturers of Class D devices outside the current categories should monitor regulatory developments and prepare for the possibility that their device type may be brought into the EURL system in future designating regulations.

The EURL Timeline

Key Dates

The Critical Cut-Offs: When EURL Requirements Apply

The regulations include important transitional provisions with different cut-off dates for different categories:

For the original four categories (hepatitis/retrovirus, herpes, bacterial, respiratory):

• Applications lodged before October 1, 2024: The Notified Body completes the assessment under the procedures in place at the time of application. EURL verification was not required for the initial conformity assessment, even if the certificate was issued after October 1, 2024.
• Applications lodged on or after October 1, 2024: The Notified Body must involve the relevant EURL for performance verification and batch testing as part of the conformity assessment process.

For the two new categories (parasite infection, blood grouping):

• Applications lodged before May 1, 2026: EURL verification is not required for the initial conformity assessment.
• Applications lodged on or after May 1, 2026: The Notified Body must involve the relevant EURL for performance verification and batch testing.

Batch testing applies from each category's respective operational date to all Class D devices within scope, including those already certified.

These cut-off dates create significant planning considerations for manufacturers. If you have a Class D device in one of the newly designated categories (parasite or blood grouping), the timing of your submission relative to May 1, 2026, determines whether EURL involvement is triggered. For the original four categories, this transition has already occurred.

How EURL Verification Works in Practice

The Relationship Between Manufacturer, Notified Body, and EURL

One of the most important aspects of the EURL system is the communication pathway. Manufacturers do not have a direct contractual relationship with the EURL. The EURL liaises directly with the Notified Body. The flow works as follows:

1. The manufacturer submits the conformity assessment application and technical documentation to the Notified Body.
2. The Notified Body reviews the documentation and identifies that the device falls within a designated EURL category.
3. The Notified Body sends the relevant samples, documentation, and test protocols to the designated EURL.
4. The EURL performs the performance verification and/or batch testing.
5. The EURL reports its findings to the Notified Body.
6. The Notified Body incorporates the EURL results into its conformity assessment decision.

This means the manufacturer interacts with the Notified Body as usual, and the Notified Body manages the EURL interface. The manufacturer does not need to negotiate terms, send samples directly to the EURL, or manage the EURL relationship independently.

Performance Verification

Under IVDR Article 100(2)(a), EURLs perform performance verification during the initial conformity assessment of Class D devices in designated categories. Performance verification means the EURL independently tests whether the device performs as claimed in the manufacturer's technical documentation.

This typically involves:

• Sample testing: The EURL tests device performance using its own reference materials, sample panels, and test protocols. This is independent of the manufacturer's own performance studies.
• Comparison against claims: The EURL evaluates whether the device's actual performance — sensitivity, specificity, accuracy, and other relevant parameters — aligns with the claims made in the technical documentation and instructions for use.
• Verification of analytical characteristics: Depending on the device type, the EURL may assess analytical sensitivity, analytical specificity, reproducibility, and other characteristics defined in the applicable Common Specifications.

Performance verification is not a repetition of the manufacturer's entire performance evaluation. It is an independent check focused on verifying key performance claims. However, the scope and depth of testing are determined by the EURL in coordination with the Notified Body and based on the requirements of the applicable Common Specifications or other relevant standards.

Batch Testing

Under IVDR Article 100(2)(b), EURLs also perform batch testing. This is the independent testing of specific production batches to verify that each batch meets the approved device specifications before it is placed on the market.

Batch testing has several important implications:

• Ongoing obligation: Unlike performance verification, which occurs during the initial conformity assessment, batch testing is a recurring requirement. Each batch of a Class D device in a designated category must be tested by the EURL before it can be released to the EU market.
• Release hold: Batches cannot be released for sale in the EU until the EURL has completed testing and confirmed that the batch meets specifications. This creates a hold point in the manufacturing and distribution process that manufacturers must plan around.
• Testing scope: The EURL tests representative samples from each batch using validated methods. The specific parameters tested depend on the device type and applicable Common Specifications.
• Potential for batch failure: If the EURL determines that a batch does not meet the approved specifications, that batch cannot be placed on the EU market. The manufacturer must investigate, take corrective action, and produce a new batch that passes EURL testing.

Batch testing represents a significant operational change for Class D manufacturers. It introduces an external dependency into the batch release process that did not exist before. Manufacturers must factor EURL testing timelines into their production scheduling, inventory management, and supply chain planning.

Common Specifications and Their Role

The Common Specifications (CS) adopted under IVDR Article 9 define the performance characteristics that Class D devices must meet. These CS are directly relevant to EURL verification because they establish the benchmarks against which the EURL tests devices.

For devices in designated EURL categories, the CS define:

• Minimum performance requirements for sensitivity, specificity, and other key parameters
• Reference materials and reference measurement procedures to be used
• Testing protocols and statistical methods for performance evaluation
• Batch release criteria

The EURL uses these CS as the basis for its verification activities. Manufacturers must ensure that their technical documentation demonstrates compliance with the applicable CS and that their devices consistently meet the specified performance requirements.

What Manufacturers Must Prepare

Technical Documentation

The technical documentation submitted to the Notified Body must support EURL performance verification. This means:

• Complete performance data: Your performance evaluation report must include comprehensive analytical and clinical performance data that demonstrates compliance with the applicable Common Specifications. Gaps or inconsistencies in performance data will be exposed when the EURL independently tests the device.
• Clear performance claims: The performance claims in your instructions for use and technical documentation must be precise and verifiable. Vague claims or claims that cannot be independently reproduced will create problems during EURL verification.
• Sample availability: You must be able to provide device samples to the Notified Body (which will forward them to the EURL) in a timely manner. This includes production-representative samples for initial verification and batch samples for ongoing batch testing.
• Reference materials: If applicable, your documentation should identify the reference materials, reference measurement procedures, and reference panels used in your own performance studies. The EURL will use its own reference materials, but understanding what you used helps contextualize your results.

Organizational Requirements

Commission Implementing Regulation (EU) 2022/944 sets out organizational requirements for EURLs, including quality management, competence, and impartiality. Manufacturers should:

• Acknowledge the EURL framework: Understand that EURL verification is a regulatory requirement for designated Class D categories, not an optional add-on.
• Prepare for extended timelines: EURL involvement adds time to the conformity assessment process. Manufacturers should plan for longer review periods, particularly for the two newest categories (parasite infection and blood grouping markers) where EURL processes are still maturing.
• Align internal processes: Ensure your internal quality management system accommodates the batch testing hold point. Your batch release procedures must include a step for EURL clearance before EU market release.
• Train your regulatory team: Ensure your regulatory affairs team understands the EURL framework, can communicate about it effectively with the Notified Body, and can prepare the technical documentation in a format that supports EURL verification.

Anticipating Delays

BSI, one of the leading IVDR Notified Bodies, has publicly noted that it has implemented processes to engage with designated EURLs. At the same time, BSI has expressed concern about certifying Class D devices without independent laboratory verification. This signals that Notified Bodies take the EURL requirement seriously and will not circumvent it.

Manufacturers should anticipate potential delays during the initial implementation period for several reasons:

• EURL capacity: Designated EURLs may face high demand as Class D manufacturers submit conformity assessment applications for the newly covered categories. Testing capacity may be constrained, particularly for popular device categories.
• Process maturation: The EURL verification process is new for everyone — EURLs, Notified Bodies, and manufacturers alike. Standard operating procedures, communication protocols, and turnaround times will take time to stabilize.
• Batch testing logistics: The logistics of batch testing — shipping samples, tracking results, integrating EURL clearance into batch release — will require new workflows for manufacturers and may encounter initial friction.

Prudent manufacturers should build buffer time into their regulatory timelines for Class D devices in the newly designated categories (parasite and blood grouping), where EURL processes are just getting underway.

Impact on the Conformity Assessment Process

How the Assessment Flow Changes

For Class D devices in designated EURL categories, the conformity assessment process under IVDR Annex IX now includes the following additional steps:

What Does Not Change

Several aspects of conformity assessment remain the same:

• The manufacturer still submits the application to the Notified Body, not to the EURL.
• The Notified Body remains the primary decision-maker for certificate issuance.
• The technical documentation requirements (Annexes II and III of the IVDR) are unchanged.
• The QMS requirements (ISO 13485 and Annex IX Chapter II) are unchanged.
• The manufacturer's own performance evaluation obligations (Article 56, Annex XIII) are unchanged — EURL verification is supplementary, not a replacement.

The EURL adds a verification layer; it does not restructure the entire conformity assessment process.

Devices Outside Designated Categories

For Class D devices that are not within any of the six currently designated EURL categories, the conformity assessment process proceeds as it did before May 2026. The Notified Body assesses the device through documentation review, QMS audit, and its own assessment procedures. There is no EURL involvement.

However, as noted above, this may change as the European Commission expands EURL coverage. Manufacturers should not assume that their Class D device will remain outside the EURL system indefinitely.

The Notified Body Perspective

BSI's Position

BSI Group, one of the most active IVDR Notified Bodies, has been transparent about its approach to EURLs. Key points from BSI's public guidance:

• BSI has implemented internal processes to engage with designated EURLs as part of Class D conformity assessment.
• BSI has signaled that independent laboratory verification is an important element of Class D assessment and has expressed reservations about certifying Class D devices without such verification.
• BSI advises manufacturers to prepare their technical documentation with EURL verification in mind, even for devices where EURL requirements may not yet apply.

This is consistent with the broader Notified Body community's approach: EURL verification is being treated as a critical component of Class D conformity assessment, not a procedural formality.

Implications for Manufacturer-Notified Body Communication

Manufacturers should discuss EURL implications with their Notified Body early in the conformity assessment process. Specific topics to address:

• Whether the device falls within a designated EURL category and, if so, which EURL will be involved.
• The Notified Body's process for engaging the EURL, including timelines and sample requirements.
• How the Notified Body will communicate EURL results to the manufacturer and how any findings will be addressed.
• The Notified Body's approach to batch testing logistics — sample sizes, shipping requirements, and turnaround time expectations.

Proactive communication with the Notified Body will help manufacturers avoid surprises and plan their regulatory timelines realistically.

Strategic Considerations for Class D Manufacturers

Assessing Your Portfolio

Every manufacturer with Class D devices on the EU market or in the pipeline should conduct a portfolio assessment:

1. Identify which devices fall within designated EURL categories. Map your Class D devices against the six categories listed above. Be precise about whether each device's intended purpose brings it within scope.

2. Determine the regulatory status of each device. Is the device already CE marked under the IVDR? Is it transitioning from the IVDD under the transitional provisions? Is it a new device not yet submitted for conformity assessment?

3. Assess timeline impact. For devices not yet submitted, factor EURL verification time into your regulatory plan. For devices with applications pending after May 1, 2026, understand that EURL involvement will be part of the process.

4. Evaluate production impact. For devices subject to batch testing, assess the impact on your production scheduling, inventory management, and distribution timelines.

Building EURL Readiness Into Your Quality System

Your quality management system should be updated to account for EURL requirements:

• Design control: Ensure that design outputs and verification activities are aligned with the applicable Common Specifications, as these form the basis for EURL testing.
• Production control: Implement batch release procedures that include the EURL testing hold point. Define responsibilities, timelines, and escalation procedures for situations where EURL testing results are delayed or a batch fails testing.
• Document control: Maintain clear traceability between your technical documentation, performance evaluation data, and the Common Specifications against which the EURL will test.
• Change management: Any changes to device design, manufacturing process, or raw materials that could affect device performance must be evaluated in the context of EURL verification. Changes may require re-verification by the EURL.

Managing Supply Chain Implications

Batch testing introduces an external dependency into your supply chain. Consider the following:

• Buffer stock: Maintain sufficient buffer stock to cover the period between batch production and EURL clearance. This is particularly important for devices with high demand or long testing turnaround times.
• Production scheduling: Align your production schedule with EURL testing capacity and turnaround times. Avoid situations where you need to release a batch faster than the EURL can test it.
• Distribution planning: Update your distribution planning to account for the EURL clearance step. Ensure that your logistics and distribution teams understand that EU market release cannot occur until EURL batch testing is complete.
• Contingency planning: Develop contingency plans for batch failures. What happens if the EURL determines that a batch does not meet specifications? How quickly can you produce and test a replacement batch?

Looking Ahead: The Future of EURL Coverage

Potential Expansion of EURL Categories

The European Commission has the authority under IVDR Article 100 to designate EURLs for additional Class D device categories beyond the six currently covered. Several factors suggest that expansion is likely:

• The IVDR's intent: Article 100 was written with the expectation that EURL coverage would eventually extend to all or most Class D device categories. The initial six categories represent a starting point, not a ceiling.
• Public health priorities: Emerging infectious diseases, pandemic preparedness, and blood safety are all areas where the EU has demonstrated a willingness to strengthen regulatory oversight. Additional EURL designations would support these priorities.
• Notified Body expectations: As Notified Bodies gain experience with the EURL framework, they are likely to advocate for expanded coverage to ensure consistent assessment standards across all Class D devices.

Manufacturers of Class D devices outside the current six categories should not assume permanent exemption. Proactive preparation — aligning technical documentation with Common Specifications, building EURL-compatible processes into the quality system, and engaging with Notified Bodies about EURL expectations — is advisable even for devices not yet subject to EURL verification.

Interaction With Other IVDR Developments

The EURL framework does not exist in isolation. It interacts with several other ongoing IVDR developments:

• Common Specifications adoption: The European Commission continues to adopt and update Common Specifications for Class D devices. These CS define the performance benchmarks that EURLs test against. Manufacturers must track CS developments for their device categories.
• Transitional provisions: The IVDR transition timeline, as amended, allows certain IVDD-certified devices to remain on the market under transitional arrangements. EURL requirements apply only to new conformity assessment applications under the IVDR, not to devices benefiting from transitional provisions. However, when the transitional period ends, all Class D devices will need full IVDR certification — and for devices in designated categories, that means EURL involvement.
• MDCG guidance: The Medical Device Coordination Group may issue additional guidance on EURL processes, sample requirements, and the interaction between EURL verification and Notified Body assessment. Manufacturers should monitor MDCG publications.

Common Misconceptions About EURLs

Misconception 1: "EURLs Replace Notified Body Assessment"

They do not. The EURL performs specific verification tasks — performance verification and batch testing — but the Notified Body remains the primary conformity assessment body. The Notified Body makes the certificate decision, conducts the QMS audit, reviews the technical documentation, and oversees ongoing surveillance. The EURL provides additional data points that the Notified Body incorporates into its assessment.

Misconception 2: "Manufacturers Choose Their EURL"

Manufacturers do not select which EURL tests their device. The EURL is designated by regulation for specific device categories. The Notified Body engages the relevant EURL based on the device category. The manufacturer has no choice in the matter.

Misconception 3: "EURL Requirements Apply to All Class D Devices Immediately"

They do not. EURL requirements apply to Class D devices in the six designated categories. For the original four categories, EURL verification has been required since October 1, 2024. For the two newest categories (parasite infection and blood grouping markers), it has been required since May 1, 2026. In each case, the requirement applies to conformity assessment applications lodged after the respective operational date. Class D devices in other categories are not yet affected.

Misconception 4: "EURL Testing Is Just a Formality"

Independent laboratory testing is not a rubber stamp. The EURL performs rigorous scientific testing against defined performance criteria. Devices that do not meet the applicable Common Specifications will fail verification. Manufacturers should treat EURL verification as a substantive scientific assessment, not a procedural checkbox.

Misconception 5: "Batch Testing Delays Will Be Negligible"

Batch testing introduces a mandatory hold point in the batch release process. While testing timelines will become more predictable as the system matures, the initial period is likely to involve variability and potential delays. Manufacturers who do not plan for this risk stock shortages and distribution disruptions.

Action Plan for Manufacturers

If you manufacture Class D IVDs intended for the EU market, take the following steps:

1. Map your portfolio against the six designated EURL categories. Identify every Class D device in your portfolio and determine whether its intended purpose falls within the scope of any designated category. Document your analysis.

2. Determine the regulatory status of each affected device. Know which devices have pending or planned conformity assessment applications and when they will be submitted relative to the applicable cut-off date (October 1, 2024 for the original four categories, May 1, 2026 for parasite infection and blood grouping markers).

3. Review your technical documentation for EURL readiness. Ensure your performance evaluation report, analytical performance data, and clinical performance data are complete, aligned with the applicable Common Specifications, and presented in a format that supports independent verification.

4. Update your quality management system. Implement batch release procedures that include the EURL testing hold point. Update your design control, document control, and change management processes to account for EURL requirements.

5. Engage your Notified Body. Discuss EURL implications for your specific devices. Understand the Notified Body's process for engaging the relevant EURL, including timelines, sample requirements, and communication protocols.

6. Build buffer into your regulatory and production timelines. EURL verification adds time to conformity assessment. Batch testing adds time to batch release. Plan for these additional steps, especially during the initial implementation period.

7. Prepare for potential expansion of EURL categories. Even if your Class D devices are not currently within designated categories, align your technical documentation and quality system with Common Specifications and EURL-ready processes. The regulatory direction is clear: EURL coverage is expanding.

8. Monitor regulatory developments. Track new Commission Implementing Regulations that may designate additional EURL categories, updates to Common Specifications, MDCG guidance on EURL processes, and communications from your Notified Body about EURL engagement.

9. Train your team. Ensure your regulatory affairs, quality assurance, and production teams understand the EURL framework, their roles in the process, and the implications for their day-to-day activities.

10. Establish contingency plans for batch failures. Define what happens if an EURL determines that a production batch does not meet specifications. Include investigation procedures, corrective action timelines, and strategies for maintaining supply during the resolution period.

Final Considerations

The introduction of EU Reference Laboratories for Class D IVDs represents a meaningful strengthening of the EU regulatory framework for the highest-risk in vitro diagnostics. It adds a layer of independent scientific scrutiny that goes beyond what Notified Bodies can achieve through documentation review alone. For manufacturers, it requires preparation, process adjustments, and realistic timeline planning.

The manufacturers who will navigate this change most effectively are those who treat EURL requirements not as an administrative burden but as an opportunity to demonstrate the robustness of their devices through independent scientific verification. The data generated through EURL testing can strengthen your device's regulatory profile, build confidence among Notified Bodies and competent authorities, and ultimately support the credibility of your products in the European market.

The framework is in place and fully operational. The original four EURL categories have been active since October 2024, and the two newest categories are now live as of May 2026. The question is not whether EURL verification will happen for Class D devices in designated categories, but how quickly manufacturers can adapt their processes to operate effectively within it.