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UDI Update: New FDA GUDID Technical Documents Released

Files on blue background

Did you know that FDA recently updated some technical documents related to GUDID submissions? On March 31, the agency sent an email to its list of GUDID email subscribers with links to an updated GUDID Data Elements Reference Table and GUDID HL7 SPL Implementation Files. The email also noted that there have been changes to the GUDID System Enhancements and Fixes page and that the system Ack3 sample messages have been updated.

If you’re dreading combing through each of those documents and webpages to determine what this all means for you, don’t worry, we already did. In this post, we’ll take a look at the details of what has changed for companies who have UDI records in the GUDID or will be submitting in the future.

New Data Attributes

Among the introduced changes to the GUDID are two new data fields–Previous DI Number and Previous DI Issuing Agency. These fields are optional and have been put in place to accommodate situations such as acquisition of a product by a new labeler company.

Here is FDA’s definition of Previous DI: “Previous Device Identifier is an identifier assigned to a version/model of a medical device prior to the assignment of a new/substitute device identifier to that same version or model, without any changes to the device itself, due to merger and acquisition activity.”

There are a few business rules governing the Previous DI field:

  • Must be in a valid format
  • Previous DI must not be the same as Primary DI
  • There can be only one Previous DI
  • Previous DI must exist as a published Primary DI in another GUDID device record
  • Previous DI can be added or edited after the grace period, but it cannot be deleted after the grace period

New Controlled Terminology

FDA has added two new terms to the Storage and Handling Units of Measure fields:

  • Inches of Mercury (in[Hg])
  • Millimeter of Mercury (mm[Hg])

These terms increase the number of available Storage and Handling Units of Measure field entries to eight.

Business Rule Updates

HIBCC Format

A new business rule requires HIBCC codes to be 6-23 digits long, have an alphabetic first character, a numeric final character, and be free of special characters, such as !, # or %.

Maximum SPL Version Number

Submission version numbers were previously limited to integers between 0 and 999. Now, the upper limit is 99,999.

Catalog Number

This field remains optional. However, FDA has added the following statement to strongly encourage labelers to include an entry in this field: “Catalog Number is critical for UDI adoption in electronic health records. Please provide catalog number as part of your device record.”

Secondary DI Post-Grace Period Editing

While Secondary DIs still may not be edited during the grace period following submission, additional Secondary DIs may be added during this time.

Changes to Ack3 Messages

The text of system-generated third acknowledgment (Ack3) sample messages has been updated to include system environment information. These new sample messages deployed to the GUDID Preproduction Environment April 7 and are scheduled to deploy to the Production environment in early June (exact date TBD).


If you’re feeling overwhelmed by the changes above and don’t know what these mean for you, contact the experts at Reed Tech. We get technical about UDI so you don’t have to.


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