2.3 GRIs 5 and 6 and Classification Doctrines

Key Takeaways

  • GRI 5(a) classifies specially shaped or fitted containers suitable for long-term use with their contents, unless the container gives the whole article its essential character.
  • GRI 5(b) covers ordinary packing materials entered with goods, but is not binding where the containers are clearly suitable for repetitive use, such as industrial gas cylinders or returnable kegs.
  • GRI 6 governs subheading classification, mandating that comparisons can occur only between subheadings at the identical hierarchical dash level (one-dash to one-dash, two-dash to two-dash).
  • Additional U.S. Rule of Interpretation 1(a) establishes that principal use provisions are governed by the use exceeding all other uses combined in the U.S. at importation, evaluated under the Carborundum factors.
  • Additional U.S. Rule of Interpretation 1(b) sets three mandatory conditions for actual use classification: declaration at entry, actual use, and verified proof of use submitted within 3 years.
Last updated: September 2026

2.3 GRIs 5 and 6 and Classification Doctrines

Quick Answer: GRI 5 governs packaging: 5(a) classifies specially shaped, durable containers (e.g., guitar cases) with their contents, while 5(b) covers ordinary packing containers but excludes repetitive-use vessels (e.g., steel gas cylinders). GRI 6 mandates that subheading classification occurs only after the 4-digit heading is established, comparing only subheadings at identical dash levels. Under Additional U.S. Rules of Interpretation, AUSR 1(a) enforces the principal use doctrine (Carborundum factors), AUSR 1(b) governs actual use (requiring entry declaration and proof within 3 years under 19 CFR 10.138), AUSR 1(c) makes a parts provision cover only products solely or principally used as such parts while subordinating that provision to any specific provision for the part, and AUSR 1(d) applies the Section XI textile-mixture principles wherever a textile material is named.

GRI 5: Cases, Boxes, and Packing Materials

Packaging materials and shipping cases represent significant value in global trade. GRI 5 provides two specific rules governing when containers are classified with their contents and when they must be classified separately.

GRI 5(a): Specially Shaped or Fitted Containers

GRI 5(a) provides that camera cases, musical instrument cases, gun cases, drawing instrument cases, necklace cases and similar containers, specially shaped or fitted to contain a specific article or set of articles, suitable for long-term use and presented with the articles for which they are intended, shall be classified with such articles when of a kind normally sold therewith.

To be classified with the article under GRI 5(a), a container must satisfy four cumulative conditions:

  1. Specially shaped or fitted: Molded, contoured, or fitted with internal cutouts or velvet grooves to hold the specific article (e.g., a fitted violin case or molded camera housing).
  2. Suitable for long-term use: Constructed of durable materials (leather, hard plastic, wood, metal) designed to protect the article throughout its useful operational life.
  3. Presented with the article: Shipped and imported together in the same consignment. (If imported empty in a separate shipment, containers are classified under their own headings, such as heading 4202).
  4. Normally sold therewith: Of a commercial type normally retailed with the article.

The Essential Character Exception: GRI 5(a) contains a vital statutory exception: "This rule does not, however, apply to containers which give the whole its essential character."

  • Classic Examples: An ornate hand-carved sterling silver tea caddy containing ordinary black tea; or a valuable cut-crystal decanter containing cheap table wine. In these instances, the container imparts the essential character under GRI 3(b), and the article is classified under the container's heading rather than the beverage heading.

GRI 5(b): Ordinary Packing Materials and Repetitive-Use Vessels

GRI 5(b) states that packing materials and packing containers entered with the goods therein shall be classified with the goods if they are of a kind normally used for packing such goods.

  • Ordinary Single-Use Packing: Cardboard boxes, bubble wrap, plastic shrink-film, styrofoam molds, and aluminum beverage cans are classified with the merchandise they enclose, taking the duty rate of the merchandise.
  • The Repetitive-Use Exception: GRI 5(b) is expressly not binding when such packing materials or packing containers are clearly suitable for repetitive use.
  • Classic Examples: Heavy-duty welded steel compressed gas cylinders (heading 7311), cryogenic transport vessels, returnable stainless steel beer kegs (heading 7310), and ISO intermodal shipping containers (heading 8609). Because these containers are industrial capital assets built for repeated round-trip voyages, they are excluded from GRI 5(b) and must be classified separately under their own respective tariff headings.

GRI 6: Subheading Classification Mechanics

GRI 6 governs the classification of merchandise at the subheading level (the 6-digit and 8-digit levels) once the 4-digit heading has been legally established:

"For legal purposes, the classification of goods in the subheadings of a heading shall be determined according to the terms of those subheadings and any related subheading notes and, mutatis mutandis, to the above rules, on the understanding that only subheadings at the same level are comparable. For the purposes of this rule, the relative section and chapter notes also apply, unless the context otherwise requires."

The Mandatory "Dash Rule"

The fundamental operational principle of GRI 6 is that only subheadings at the same hierarchical dash level can be compared:

  1. Establish the correct 4-digit heading under GRIs 1 through 5.
  2. Within that heading, compare only one-dash (-) subheadings against other one-dash subheadings. Select the most specific one-dash subheading.
  3. Once the correct one-dash subheading is selected, move down to compare the two-dash (--) subheadings nested beneath it against each other. Select the correct two-dash subheading.
  4. Repeat this discipline for three-dash and four-dash levels.
Heading 8415 (Air conditioning machines)
  ├── 8415.10 (-) Window or wall types, self-contained
  │     ├── 8415.10.30 (--) Incorporating a refrigerating unit
  │     └── 8415.10.60 (--) Other
  └── 8415.20 (-) Of a kind used for persons, in motor vehicles

Strict Prohibition: You can never compare a one-dash subheading under Heading 8415 to a two-dash subheading under Heading 8415. Nor can you compare a two-dash subheading under 8415.10 to a two-dash subheading under 8415.20.


Additional U.S. Rules of Interpretation (AUSR)

In addition to the international GRIs, Congress enacted the Additional U.S. Rules of Interpretation — a single rule with four subparagraphs, 1(a) through 1(d) — governing classification doctrines unique to the United States.

AUSR 1(a): The Principal Use Doctrine

AUSR 1(a) provides:

"In the absence of special language or context which otherwise requires—a tariff classification controlled by use (other than actual use) is governed by the principal use in the United States at or immediately prior to the date of importation, of goods of that class or kind to which the imported goods belong, and the controlling principal use is that which exceeds all other uses combined."

Key requirements of AUSR 1(a):

  1. Use of the Class or Kind: Principal use is not determined by how a specific importer intends to use an individual shipment. It is determined by the predominant commercial use throughout the United States of the entire "class or kind" to which the imported merchandise belongs.
  2. Exceeds All Other Uses Combined: Principal use requires a quantitative threshold exceeding 50% of total commercial utilization across the class or kind in the United States.
  3. Temporal Anchor: Evaluated at or immediately prior to the date of importation.

The Seven Carborundum Factors

In the landmark decision United States v. Carborundum Co., 536 F.2d 373 (CCPA 1976), the court established seven evidentiary factors used by CBP and courts to determine whether an imported article falls within a particular "class or kind":

  1. General physical characteristics of the merchandise.
  2. Expectation of the ultimate purchasers regarding the product's function.
  3. Channels, class, or kind of trade in which the merchandise moves.
  4. Environment of sale (accompanying literature, packaging, retail display).
  5. Use in the same manner as merchandise that defines the class.
  6. Economic practicality of so using the imported merchandise.
  7. Recognition in the trade of this use.

AUSR 1(b): The Actual Use Doctrine

AUSR 1(b) governs tariff provisions that make favorable duty treatment conditional upon how the specific imported merchandise is actually utilized. AUSR 1(b) establishes three mandatory cumulative conditions:

  1. Declaration at Entry: The intended actual use must be declared on CBP Form 7501 at the time of entry.
  2. Actual Use in Fact: The merchandise must be actually so used in the United States.
  3. Proof of Use Within 3 Years: Satisfactory proof of such actual use must be furnished to CBP within 3 years from the date of entry in accordance with 19 CFR 10.131 through 10.139 (specifically 19 CFR 10.138).

Consequence of Failure: Liquidation of actual use entries is suspended pending submission of proof. If the importer fails to furnish verified proof of actual use within the statutory 3-year timeframe, CBP liquidates the entry at the higher duty rate applicable to the general non-use provision.

FeaturePrincipal Use (AUSR 1(a))Actual Use (AUSR 1(b))
Governing StandardUse of the entire class or kind across the U.S.Actual use of the specific imported shipment.
ThresholdExceeds all other uses combined (> 50%).100% of imported shipment must be actually so used.
Entry DeclarationNormal tariff classification.Specific intended use must be declared on CBP Form 7501.
Post-Entry ProofNone required for specific entry.Verified proof required within 3 years (19 CFR 10.138).
Failure ConsequenceReclassification based on trade data.Liquidation at higher non-actual use duty rate.

AUSR 1(c): Parts Provisions

AUSR 1(c) has two operative halves, and the CBLE tests both:

"a provision for parts of an article covers products solely or principally used as a part of such articles but a provision for 'parts' or 'parts and accessories' shall not prevail over a specific provision for such part or accessory."

  1. The coverage half: a "parts" provision reaches only products solely or principally used as a part of the named article. A generic component sold across many industries is not drawn into a parts provision for one of them merely because it can be used there.
  2. The subordination half: where a specific provision describes the part itself, that specific provision prevails over the general parts provision.
    • Example: custom-molded tempered safety glass windows built to the blueprint of a commercial airliner. Heading 7007 provides eo nomine for safety glass; heading 8807 provides for "Parts of goods of heading 8802 or 8806 (aircraft)." Under the second half of AUSR 1(c), the specific provision for safety glass in heading 7007 prevails over the general aircraft-parts provision.

AUSR 1(d): Textile Material Mixtures

AUSR 1(d) is not a parts rule — a frequent point of confusion on the exam. It provides:

"the principles of section XI regarding mixtures of two or more textile materials shall apply to the classification of goods in any provision in which a textile material is named."

Its effect is to export the Section XI blending rules to any provision anywhere in the tariff that names a textile material. Under the Section XI notes, goods of a mixture of two or more textile materials are classified as if consisting wholly of the one textile material that predominates by weight over each other single textile material; where no one material predominates by weight, the good is classified as if consisting wholly of the material covered by the heading that occurs last in numerical order among those equally meriting consideration.

Parts of General Use — a Section Note Rule, Not AUSR 1(d)

Parts of general use — base metal screws, bolts, nuts, washers, springs, chains, and similar articles — are excluded from classification as parts of machinery, electrical equipment, or vehicles. That exclusion comes from the Section Notes: Section XV Note 2 defines parts of general use, and Section XVI Note 1(g) and Section XVII Note 2(b) exclude them from those sections. It does not come from the Additional U.S. Rules. A steel bolt engineered for an automobile engine is classified under heading 7318 as a threaded steel fastener, not under heading 8708 as an automotive part.


Classification Doctrines: Eo Nomine vs Use Provisions

Tariff headings are fundamentally categorized into two operational doctrines:

  1. Eo Nomine Provisions: An eo nomine heading describes a commodity by its specific name (e.g., "horses", "microscopes", "vacuum cleaners", "bicycles").
    • Legal Scope: An eo nomine provision includes all forms, varieties, and improvements of the named article developed after the tariff was enacted, provided the essential character remains unchanged (Nidec Corp. v. United States). It includes incomplete or unfinished versions having essential character under GRI 2(a).
  2. Use Provisions: A use provision classifies merchandise according to its function, purpose, or intended operation rather than its physical identity (e.g., "machinery for soil preparation", "apparatus for measuring electrical quantities").
    • Legal Scope: Governed by AUSR 1(a) (principal use) or AUSR 1(b) (actual use).
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GRI 5/6 and Additional U.S. Rules Classification Logic
Test Your Knowledge

An importer enters specialized chemical additives under an actual use tariff provision carrying a 0% duty rate. If entered under the alternative general basket heading, the chemical is dutiable at 6.5%. The importer timely declares the intended actual use on CBP Form 7501 at entry. However, due to internal company restructuring, the importer fails to submit verified proof of actual use to CBP within 3 years from the date of entry. What is the legal consequence under Additional U.S. Rule of Interpretation 1(b) and 19 CFR 10.138?

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Test Your Knowledge

An ocean consignment contains two distinct articles: (1) high-end custom electric guitars packed inside plush-lined, contoured hardshell wooden cases designed for lifetime protection; and (2) 150 refillable, heavy-duty welded steel cylinders containing compressed industrial argon gas. Under GRI 5, how are the guitar cases and argon gas cylinders classified?

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Test Your Knowledge

An importer imports laminated safety glass panels that have been cut and contoured to exact engineering blueprint dimensions exclusively for installation as cockpit windshields in commercial passenger aircraft. Heading 7007 provides for 'Safety glass, consisting of toughened (tempered) or laminated glass,' while heading 8807 provides for 'Parts of goods of heading 8802 or 8806 (aircraft).' Under Additional U.S. Rule of Interpretation 1(c), what is the correct classification?

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