When one template can serve two regimes

Where the law itself converged first

FDA's Quality Management System Regulation, effective February 2, 2026, replaced most of Part 820 with a direct incorporation of ISO 13485:2016 as its own regulatory text — this blog has already covered what stayed FDA-specific on top of that base, and what happened to the DMR, DHF, and DHR once QMSR folded their content into the standard's own Clause 4.2. On the EU side, Article 10(9) of MDR never named ISO 13485 as its literal requirement — certification against the standard is evidence toward that paragraph, not a substitute for it, a distinction this blog has drawn directly — but the standard is still what a notified body actually expects a manufacturer's quality management system to be built to in practice. The result of QMSR's fold-in: a CAPA tracker built around Clause 8.5.2 and 8.5.3, or a design-controls file built around Clause 7.3, now serves both regimes off the identical citation. One incorporates the clause as law; the other treats it as the working evidence a notified body will actually check. The clause number on the page is the same either way.

Where it never converged, and won't

Convergence at the standard level doesn't reach the documents that answer to one country's own statute rather than to ISO 13485. A periodic safety update report exists because MDR Article 86 requires one, on a schedule set by device class, for a device sold in the EU; nothing in the FD&C Act asks an FDA-regulated manufacturer for a PSUR, and a US-market device generating one anyway has produced a document nobody required. A Refuse-to-Accept review checks a 510(k)'s completeness against an FDA-specific procedure with no MDR equivalent at all — a technical file goes to a notified body under Annex II's own index requirement instead, a different completeness logic entirely. And a 483 response answers a specific FDA inspection instrument that MDR's own audit regime, run by notified bodies rather than by a government agency, never produces in the first place. None of these three has a foreign twin waiting to be merged with. They were never the same document wearing two flags.

The mistake runs in both directions

Building two versions of a converged document wastes exactly the maintenance the convergence was supposed to save — two copies of the same ISO 13485 citation, checked separately, drift apart the moment one gets updated and the other doesn't, which is the staleness failure mode this shelf already watches for on a single citation, now doubled for no reason. But forcing one document across a boundary the law itself doesn't cross is the opposite mistake, and it's the more common one in practice: a “global” PSUR-style summary handed to a US quality team, or an RTA-style completeness checklist handed to an EU submissions team, both produce a document that looks like it answers a requirement without answering any requirement either team's regulator actually enforces.

How the shelf decides

The test we apply isn't whether a company operates in both markets — it's whether the same legal text governs the document in both markets. Where QMSR's incorporation of ISO 13485 means yes, a resource ships once, with both governing references named on the page. Where it means no — a PSUR, an RTA checklist, a 483 response, and most of the rest of the file besides — the shelf ships a US version and an EU version as two separate, separately sourced resources, because merging them would hide the exact distinction a team needs to know it's looking at. The launch catalog tags every resource with the source it actually answers to, for exactly this reason. If you've found a place we've drawn that line wrong, the shelf takes that correction directly.