DMF Type III: FDA Drug Master File for Packaging Materials

A Type III Drug Master File (DMF) is a confidential submission to the U.S. Food and Drug Administration that documents a packaging material, so that a drug applicant can reference it in support of their own FDA filing without the packaging supplier having to disclose proprietary details to the customer. Type III is the DMF category for packaging materials. The supplier files it with the FDA, keeps it current, and authorises customers to reference it through a Letter of Authorization (LOA). It is a procurement-critical asset: a customer filing a new or generic drug application for the U.S. market can lean on the supplier’s DMF instead of re-documenting the packaging themselves.

This guide explains what a DMF is, what a Type III DMF contains, how the Letter of Authorization works, and why holding a DMF matters for a packaging supplier and its customers.

Key takeaways

A Drug Master File is a confidential FDA submission with detailed information used in the manufacturing, processing, packaging, and storing of a drug; the holder submits it and controls who may reference it.
Type III is the DMF category for packaging materials. Other current types cover drug substances and intermediates (Type II), excipients, colorants, and flavours (Type IV), and FDA-accepted reference information (Type V).
A DMF is not approved or disapproved on its own; the FDA reviews it only when it is referenced in support of an application (an NDA, ANDA, or another DMF).
Customers reference a DMF through a Letter of Authorization (LOA): a written statement from the DMF holder permitting the FDA to consult the file in support of the customer’s submission.
A Type III DMF typically documents the packaging material’s intended use, components, composition, controls, supplier information, acceptance specifications, and supporting data, including toxicological data where relevant.
Holding a DMF lets a supplier protect its proprietary formulation and process while still supporting customers’ U.S. regulatory filings.

What is a Drug Master File?

A Drug Master File is a submission to the FDA that provides confidential, detailed information about a facility, process, or article used in the manufacturing, processing, packaging, or storing of a human drug. It is described in the FDA’s Drug Master Files guidance.

A DMF exists to solve a confidentiality problem. A packaging supplier’s exact material composition and process are proprietary, but the FDA needs that information to evaluate a drug application that uses the packaging. By filing a DMF, the supplier gives the FDA the detail directly, and then authorises its customer’s application to reference the file, so the customer never has to see the confidential content. The DMF is submitted at the supplier’s own initiative; it is neither approved nor rejected in isolation, and it carries a DMF number used for reference.

The DMF types, and where Type III sits

The FDA groups DMFs by the kind of information they hold; Type III is packaging materials. The current types are:

Type	Subject
Type II	Drug substance, drug substance intermediate, and material used in their preparation, or drug product
Type III	Packaging material
Type IV	Excipient, colorant, flavour, essence, or material used in their preparation
Type V	FDA-accepted reference information

Type I (facilities and personnel) was discontinued in 2000. A packaging component that contacts the drug, such as an aluminium and aluminium-plastic vial seal, falls under Type III, since it documents the packaging material and its suitability for the intended use.

What a Type III DMF contains

A Type III DMF documents the packaging material in enough detail for the FDA to judge its suitability for its intended use. The FDA’s guidance indicates a Type III submission should identify each packaging material and provide the information needed to support an application that references it. In broad terms it includes:

Identification and intended use. What the material is and the drug-contact application it is intended for.
Components and composition. The materials of construction and the composition of the packaging component.
Controls for release. The specifications and controls applied when releasing the material.
Supplier and fabricator information. The names of the suppliers or fabricators of the components used, and their acceptance specifications.
Supporting data. Data supporting the acceptability of the material for its intended use, including toxicological data where it is not otherwise available by cross-reference to another file.

Taken together, this lets the FDA confirm that the packaging is suitable and controlled, on behalf of the drug applications that reference the DMF, while the confidential detail stays between the supplier and the FDA.

How the Letter of Authorization works

A customer references a DMF by including a Letter of Authorization from the DMF holder in their FDA submission; the LOA is the mechanism that connects the two. The process is straightforward:

The DMF holder (the packaging supplier) submits and maintains the DMF, which receives a DMF number.
When a customer wants to use the packaging in a U.S. drug application, the holder issues a Letter of Authorization naming that customer and permitting the FDA to reference the DMF in support of their submission.
The customer cites the DMF number and includes the LOA in their application, and the FDA reviews the DMF as part of assessing that application.

The LOA should identify the DMF and the specific item being authorised, and be signed by the DMF holder. This keeps the supplier in control: only authorised customers can rely on the file, and the holder can support many customers from a single, maintained DMF. Because a current DMF and a prompt LOA can be prerequisites for a customer’s U.S. filing, the supplier’s DMF is often a procurement checkbox.

How this works in practice at Autofits

Autofits holds a Drug Master File (DMF 18100) with the FDA, which supports customers filing drug applications for the U.S. market. A customer using Autofits seals in a U.S. product can reference the DMF via a Letter of Authorization, so Autofits’s proprietary material and process detail is provided to the FDA directly rather than disclosed to the customer. The DMF sits alongside Autofits’s broader quality credentials: an ISO 15378:2017 quality system, ISO 9001:2015 and ISO 14001:2015 certification, and CFDA registration (B20200000501). The FlipTop Optima flip-off seals, tear-off and tear-down aluminium seals, and aluminium pilfer-proof (ROPP) caps are made from documented, controlled materials, AA8011 aluminium alloy, epoxy lacquer conforming to 21 CFR 175.300, and polypropylene conforming to 21 CFR 177.1520, in a 75,000 sq ft facility in Nashik, India, with an ISO Class 8 cleanroom and high-speed visual inspection.

Frequently asked questions

What is a Type III Drug Master File?

A Type III DMF is the FDA Drug Master File category for packaging materials. A packaging supplier files it with the FDA to document the material’s intended use, components, composition, controls, and supporting data, so that a drug applicant can reference the packaging in a U.S. filing without the supplier disclosing proprietary detail to them.

Does the FDA approve a DMF?

No. A DMF is neither approved nor disapproved on its own. The FDA reviews the DMF only when it is referenced in support of an application, such as a new drug application (NDA), abbreviated new drug application (ANDA), or another DMF. The DMF is a reference file, not a standalone approval.

What is a Letter of Authorization?

A Letter of Authorization (LOA) is a written statement from the DMF holder permitting the FDA to reference the information in the DMF in support of another party’s submission. The customer includes the LOA and cites the DMF number in their application; the LOA should identify the DMF and the item authorised and be signed by the holder.

Why does a Type III DMF matter in procurement?

A current Type III DMF and a prompt LOA can be prerequisites for a customer’s U.S. drug filing. A supplier that holds and maintains a DMF can support customers’ U.S. submissions quickly and confidentially, which is why buyers often ask whether a packaging supplier holds a DMF before selecting it.

What is the difference between Type II and Type III DMFs?

Type II DMFs cover drug substances, intermediates, materials used in their preparation, or drug products. Type III DMFs cover packaging materials. A vial seal or cap that contacts or encloses the drug is documented under Type III, since it is a packaging material rather than an active or drug substance.

Sources

U.S. FDA: Types of Drug Master Files (DMFs) (https://www.fda.gov/drugs/drug-master-files-dmfs/types-drug-master-files-dmfs)
U.S. FDA: Drug Master Files (DMFs) overview (https://www.fda.gov/drugs/forms-submission-requirements/drug-master-files-dmfs)
U.S. FDA: Guideline for Drug Master Files (https://www.fda.gov/drugs/drug-master-files-dmfs/guideline-drug-master-files-dmf)

“`json { “@context”: “https://schema.org”, “@graph”: [ { “@type”: “Article”, “headline”: “DMF Type III: FDA Drug Master File for Packaging Materials”, “description”: “A Type III Drug Master File is a confidential FDA submission documenting a packaging material, referenced by drug applicants through a Letter of Authorization to support U.S. filings.”, “author”: {“@type”: “Organization”, “name”: “Autofits Technical Team”}, “publisher”: { “@type”: “Organization”, “name”: “Autofits Packaging Pvt. Ltd.”, “address”: { “@type”: “PostalAddress”, “streetAddress”: “E-13/7/4, MIDC, Malegaon, Sinnar”, “addressLocality”: “Nashik”, “addressCountry”: “IN” } }, “datePublished”: “2026-07-06”, “dateModified”: “2026-07-06” }, { “@type”: “FAQPage”, “mainEntity”: [ {“@type”: “Question”, “name”: “What is a Type III Drug Master File?”, “acceptedAnswer”: {“@type”: “Answer”, “text”: “A Type III DMF is the FDA Drug Master File category for packaging materials. A packaging supplier files it with the FDA to document the material’s intended use, components, composition, controls, and supporting data, so that a drug applicant can reference the packaging in a U.S. filing without the supplier disclosing proprietary detail to them.”}}, {“@type”: “Question”, “name”: “Does the FDA approve a DMF?”, “acceptedAnswer”: {“@type”: “Answer”, “text”: “No. A DMF is neither approved nor disapproved on its own. The FDA reviews the DMF only when it is referenced in support of an application, such as a new drug application (NDA), abbreviated new drug application (ANDA), or another DMF. The DMF is a reference file, not a standalone approval.”}}, {“@type”: “Question”, “name”: “What is a Letter of Authorization?”, “acceptedAnswer”: {“@type”: “Answer”, “text”: “A Letter of Authorization (LOA) is a written statement from the DMF holder permitting the FDA to reference the information in the DMF in support of another party’s submission. The customer includes the LOA and cites the DMF number in their application; the LOA should identify the DMF and the item authorised and be signed by the holder.”}}, {“@type”: “Question”, “name”: “Why does a Type III DMF matter in procurement?”, “acceptedAnswer”: {“@type”: “Answer”, “text”: “A current Type III DMF and a prompt LOA can be prerequisites for a customer’s U.S. drug filing. A supplier that holds and maintains a DMF can support customers’ U.S. submissions quickly and confidentially, which is why buyers often ask whether a packaging supplier holds a DMF before selecting it.”}}, {“@type”: “Question”, “name”: “What is the difference between Type II and Type III DMFs?”, “acceptedAnswer”: {“@type”: “Answer”, “text”: “Type II DMFs cover drug substances, intermediates, materials used in their preparation, or drug products. Type III DMFs cover packaging materials. A vial seal or cap that contacts or encloses the drug is documented under Type III, since it is a packaging material rather than an active or drug substance.”}} ] }, { “@type”: “BreadcrumbList”, “itemListElement”: [ {“@type”: “ListItem”, “position”: 1, “name”: “Standards”, “item”: “/standards/”}, {“@type”: “ListItem”, “position”: 2, “name”: “DMF Type III”, “item”: “/standards/dmf-type-iii/”} ] } ] } “`

*Last updated: 2026-07-06. This article is general regulatory information, not legal or compliance advice; confirm current regulatory text and requirements with the FDA.*