How classification works
MDR classification rules are in Annex VIII of MDR 2017/745. IVDR classification rules are in Annex VIII of IVDR 2017/746. Classification determines the conformity assessment route, notified body involvement, and post-market obligations.
This site provides general information only and does not constitute legal or regulatory advice. Always consult the official regulation text and a qualified regulatory professional.
Why classification matters
Classification is the first regulatory decision a manufacturer must make. It determines:
- Which conformity assessment procedure applies
- Whether a notified body must be involved
- The depth of clinical or performance evidence required
- Post-market obligations including PSUR frequency
- EUDAMED registration requirements
Getting classification wrong — in either direction — has serious consequences. Under-classifying a device risks placing an inadequately assessed product on the market. Over-classifying wastes resources and delays access.
MDR and IVDR use separate systems
MDR and IVDR have entirely separate classification systems:
| Regulation | Classes | Legal basis |
|---|---|---|
| MDR 2017/745 | Class I (and sub-classes Is, Im, Ir), IIa, IIb, III | Annex VIII, Rules 1–22 |
| IVDR 2017/746 | Class A, B, C, D | Annex VIII, Rules 1–7 |
The two systems are not equivalent and cannot be mapped directly to each other. A Class IIa MDR device is not the same risk level as a Class B IVDR device.
The MDR classification approach
MDR classification is rule-based, applying 22 classification rules found in Annex VIII. The rules are organised by device type:
| Rule group | Covers |
|---|---|
| Rules 1–4 | Non-invasive devices |
| Rules 5–8 | Invasive devices |
| Rules 9–13 | Active devices |
| Rules 14–22 | Special rules (substances, devices for specific anatomical locations, software, nanomaterials, etc.) |
The classification process — MDR
- Identify the intended purpose of the device precisely
- Determine whether it is invasive, non-invasive, or active
- Apply the relevant classification rules in order
- Where more than one rule could apply, the highest resulting class prevails (Annex VIII §3.3)
- Document the classification rationale in the technical documentation
Key MDR classification definitions
| Term | Definition (MDR Annex VIII) |
|---|---|
| Invasive device | Device that penetrates the body surface, including body orifices |
| Surgically invasive device | Invasive device introduced into the body through a surgical incision |
| Implantable device | Intended to be totally introduced into the body, or replace epithelial or ocular surface |
| Active device | Depends on a source of energy other than that generated by the human body or gravity |
| Duration: transient | Intended for continuous use < 60 minutes |
| Duration: short-term | Intended for continuous use 60 min – 30 days |
| Duration: long-term | Intended for continuous use > 30 days |
The IVDR classification approach
IVDR classification uses 7 rules in Annex VIII, reflecting the risk posed by the diagnostic information generated rather than physical interaction with the body. The framework is risk-based:
| Class | Risk profile | Examples |
|---|---|---|
| A | Lowest risk — instruments and ancillary products | General laboratory instruments, specimen receptacles |
| B | Low-to-medium risk | Most routine diagnostics (haematology, clinical chemistry) |
| C | Medium-to-high risk — significant impact on patient management | Blood glucose, CRP, companion diagnostics, HIV screening |
| D | Highest risk — life-threatening conditions or high transmission risk | Blood group typing, HIV confirmation, NAT for blood screening |
Manufacturer's classification responsibility
Classification is the manufacturer's responsibility. There is no pre-submission or approval process for classification decisions in the EU (unlike the US FDA, which offers pre-submission meetings and formal classification orders).
However:
- Notified bodies review and may challenge classification as part of conformity assessment
- National Competent Authorities can issue opinions on classification questions (not binding EU-wide)
- The MDCG publishes borderline and classification guidance
If the manufacturer and a notified body disagree on classification, the matter may be referred to the relevant NCA.
Reclassification
The European Commission has the power to reclassify individual devices or device categories where new evidence or safety concerns emerge. This is done via implementing acts under Art. 51(2) MDR and Art. 47(2) IVDR. See Reclassification & SCENIHR opinions.
Related pages
- Class I · IIa · IIb · III — MDR classes
- Classification rules 1–22
- Class A · B · C · D — IVDR classes
- Classification rules 1–7
- Software & SaMD classification
- Borderline & combination products
Official references
| Reference | Description |
|---|---|
| MDR Annex VIII | Classification rules 1–22 |
| IVDR Annex VIII | Classification rules 1–7 |
| MDR Art. 51 | Classification of devices |
| IVDR Art. 47 | Classification of IVDs |
| MDCG 2021-24 | Software classification guidance |
| MDCG 2022-5 | Borderline and classification |