UK MDR 2002 Part II, III and IV: Scope and Registration

1. Key takeaways

The UK MDR 2002 runs on three parallel substantive parts: Part II (regulations 5–19C) for general devices, Part III (regulations 20–31) for active implantable devices and Part IV (regulations 32–44ZB) for IVDs. Each part carries its own independent scope provision (regulations 6, 21 and 33 respectively), its own essential requirements (regulations 8, 22 and 34), its own marking provision (regulations 10, 24 and 36), its own conformity assessment procedure provision (regulations 13, 27 and 40) and its own registration provisions (regulations 7A and 19, regulations 21A and 21B, and regulations 33A and 44). Determining which part a product belongs to is the first fork in the road for any United Kingdom compliance project. Get the part right and every downstream obligation — classification, labelling, conformity assessment, registration and surveillance — follows in a predictable sequence; get it wrong and the entire compliance file is built on the wrong foundation, with errors surfacing only when documentation is examined.

2. Legal basis

The relevant provisions sit in a single instrument, but they must be read part by part, because the numbering differs across the three tracks:

• UK MDR 2002 (SI 2002/618, as amended): regulation 6 (scope of Part II), regulation 8 (essential requirements for general devices), regulation 10 (UK marking for general devices), regulation 13 (affixing procedure), and regulations 7A and 19 (registration of general devices); regulation 21 (scope of Part III), regulations 22, 24 and 27, and regulations 21A and 21B (registration of active implantable devices); regulation 33 (scope of Part IV), regulations 34, 36 and 40, and regulations 33A and 44 (registration of IVDs).

Although the three parts mirror one another structurally, the provision numbers differ, and each registration pair must be matched to its own part. A matrix that maps scope, essential requirements, marking, assessment and registration provisions against Part II, Part III and Part IV is the most reliable way to keep the three tracks apart in day-to-day work, and it doubles as a training tool for new compliance staff.

3. Expert insights

Insight 1: the registration provisions are not symmetric across the three parts. General devices and active implantable devices each have two registration provisions (general devices: regulations 7A and 19; active implantable devices: regulations 21A and 21B), and IVDs likewise have two (regulations 33A and 44). The reason is that each part distinguishes between ordinary devices and custom-made devices as two categories of registration obligation. Custom-made devices are not exempt from registration; they simply follow a different provision. Companies that assume custom-made status removes the registration duty entirely create a silent gap in their compliance records, one that only becomes visible when MHRA registration data is reviewed or when a distributor requests evidence of registration.

Insight 2: Part III is a legacy stand-alone part. Active implantable devices were originally governed in the European Union by the separate Directive 90/385/EEC, and the United Kingdom retained that split structure. As a result, active implantable devices in Great Britain never pass through the Part II classification system and are not graded Class I, IIa, IIb or III — they form a category of their own. Companies calibrated to the integrated logic of the EU MDR frequently misalign here, for example by searching the general classification rules for a grading that the British system never assigns to active implantable devices in the first place.

Insight 3: cross-part products need dedicated handling. Products that straddle boundaries — devices incorporating medicinal substances, devices utilising tissues of animal origin and similar hybrid categories — are covered in the United Kingdom by dedicated provisions (for example, regulation 19A adds requirements concerning the use of animal tissues). Assigning such a product to a single part and treating the compliance obligations as exhausted at that point is unsafe: the additional provisions must be checked on their own terms, and the analysis recorded.

4. Practical recommendations

GRZAN recommends issuing a part attribution memorandum at the start of every United Kingdom project. The memorandum should state which scope provision (regulation 6, 21 or 33) the conclusion rests on, record the reasons for excluding the other parts, and address the two special routes in the same document: system and procedure packs (regulation 14) and custom-made devices (regulation 15). This file serves a dual function. Internally, it is the technical baseline against which classification, labelling and registration work is planned. Externally, it is supporting material for UKRP due diligence and for MHRA data verification, where the ability to show the reasoning — not just the conclusion — materially shortens the review cycle and reduces the risk of follow-up questions.

5. Verification checklist

• □ Part attribution has been determined under regulation 6 / 21 / 33
• □ Whether the product falls under the custom-made device or system procedure pack special route has been confirmed
• □ Whether additional requirements such as animal tissues apply (regulation 19A) has been confirmed
• □ The marking and conformity assessment provisions of the relevant part have been confirmed
• □ The attribution memorandum has been archived and is available for UKRP reference

Legal information verified as of 29 October 2026.

GRZAN supports manufacturers with the following services for the United Kingdom market:

• Appointment of the UK Responsible Person (UKRP) and signature support for the letter of authorisation
• End-to-end MHRA registration (DORS) filing and account lifecycle management
• Device classification determination, GMDN code selection and annual registration fee estimation
• Dual-track design for Great Britain and Northern Ireland, including UK(NI) solutions
• Post-market surveillance (PMS) system setup, PMSR/PSUR preparation and vigilance report submission
• Emergency response to serious incidents and field safety corrective actions (FSCA)
• Monitoring of UK regulatory changes and compliance gap assessment

GRZAN provides end-to-end MHRA registration and compliance support for manufacturers entering the United Kingdom market, covering every stage from market entry planning through post-market obligations. For enquiries, contact info@grzanglobal.com.