How to read a device’s UDI record in GUDID

Every device on the market carries an identifier most people never learn to read closely — a Unique Device Identifier, or UDI, printed on the label and matched to a public record in an FDA database. It exists so a specific device, in a specific lot, can be traced back to what it actually is without anyone having to call the manufacturer and ask. Reading the label is only half of it. The record FDA keeps about that device is the other half, and the two aren’t the same document.

What the two halves are for

A single catheter model has one DI, shared by every unit of that model FDA has ever cleared under it. The specific box sitting in front of you also carries a PI recording its own lot number and expiration date — data that’s specific to that box, not the model as a whole. The DI is what gets registered centrally in GUDID; the PI generally isn’t, because per-unit data isn’t practical to hold in a central database the way a fixed device-level record is. You read the PI off the physical label or its barcode at the point of use, not by looking anything up.

Reading a GUDID record

A public GUDID record carries the brand name, the labeler (the company responsible for the device under FDA’s regulations, not necessarily the manufacturer), a device description, and the product code and device classification pulled from FDA’s own classification system — the same fields covered in how to read a product classification entry, attached here to one specific commercial device instead of an entire regulation. It also states whether the device is labeled for single use, whether it’s sterile, and which issuing agency — GS1, HIBCC, or ICCBBA — assigned the identifier’s format. None of that is marketing copy; every field on the record is something FDA’s UDI rule requires the labeler to submit and keep current.

When a new DI is required

Not every change to a device requires a new identifier. The issuing agencies’ own standards, which FDA’s UDI framework incorporates, set out when a change is significant enough to require a new DI rather than a labeling update to the existing one — broadly, changes that affect the device’s identity or the attributes the record itself captures. It’s a closely related judgment to knowing whether a device change requires a new 510(k) at all: same instinct, different consequence, and worth treating as a companion question rather than an independent one.

If your first UDI lookup is prompted by a recall, the DI is only the starting point — pair it with how to read an FDA recall for what to actually do with the PI on the units in front of you, and see how to read a product classification entry for more on the regulation and product code fields that show up again in every GUDID record.