Article Ref: F-047

Weights and Measures Connection, Vol. 8, Issue 4 Page 1

The Display of Packages in Retail Stores and the Principal Display Panel 

Requirement for Packaged Goods

Byline: David Sefcik

This article provides information on two related but distinctly different packaging and labeling issues. The first relates 

to the retail display of packages. The second explains the Uniform Packaging and Labeling Regulation’s requirements 

for determining the Principal Display Panel (PDP) of a package, and some possible solutions to a reoccurring problem 

involving PDP placement on so called “fragile” (e.g., bakery) products are also provided. 

Part 1. Package Display in Retail Stores

One question that weights and measures inspectors often ask during Office of Weights and Measures (OWM) training 

classes on packaging and labeling is if the Uniform Packaging and Labeling Regulation (UPLR) in NIST Handbook 

130 “Uniform Laws and Regulations in the Areas of Legal Metrology and Engine Fuel Quality” 

www.nist.gov/pml/weights-and-measures/publications/nist-handbooks/handbook-130 requires retailers to display, 

present, or show packaged goods on retail store shelves so that the Principal Display Panel (PDP) (which must display 

product identity and net quantity declarations) is always visible to the consumer. 

While OWM recommends that retailers display the PDP of packages so that the product identity and net contents are 

always visible, the UPLR does not include requirements about the display of packages on store shelves. The UPLR 

only prescribes the requirements on how packages are to be labeled by manufacturers and packers. 

Although there are no package display requirements in the UPLR, most, but not all (see Figure 1) retailers stock their 

shelves so the PDPs, which typically includes the brand name and must include the product identity and net quantity 

of contents, are easily viewed by consumers (see Figure 2). The display pictured in Figure 2 is a common display 

practice in most retail stores because manufacturers and packers spend millions of dollars to promote their brand 

names and trademarks through advertising and labels designed to attract consumer attention. 

Retailers inherently display packages so consumers will not have to pick up or handle the package to see the brand 

name, product identity, and the quantity stated on the package. However, for most packages of food, consumers often 

Figure 1. Packages displayed in shipping 

cartons where the full PDP (identity and 

net content) is not visible.

BOTH METHODS 

OF DISPLAYING 

PACKAGES ARE 

PERMISSIBLE

Figure 2. Packages displayed with the 

PDP visible to consumers without the 

need for them to handle the package.
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Weights and Measures Connection, Vol. 8, Issue 4 Page 2

handle the product to read the ingredient, nutrition, and other useful information placed on the side or back of a 

package. 

There are other situations as well, where the PDP of packages are often not visible when they are displayed. For 

example, properly labeled packages of cheese or turkeys are often placed in display coolers, shelves, or bins where a 

consumer cannot view the PDP, which is often a random weight label bearing the product identity, net weight, total 

price and unit price of the product (See Figure 3). Since consumers habitually pick up packages to read the label, it is 

not uncommon for them to return the products to the wrong location on the shelf or to place the package back on the 

shelf with the PDP hidden. This is the reason that the UPLR regulations do not consider a package that is displayed 

with the PDP out of view to be a violation (see also Figure 4).

The Food and Drug Administration (FDA) confirmed the Federal Fair Packaging and Labeling Act (FPLA) (originally 

in 2000 and again in July 2017) that, like the UPLR, neither nor the Food Drug and Cosmetic Act (FDCA) include 

requirements that apply to the display of packages on the shelves of retail stores. The UPLR and federal regulations 

only define the PDP and specify what information must appear on it. The criteria for deciding which panel(s) the PDP 

is placed on for display, presentation, or examination of packages at retail is determined by the manufacturer, either 

by design or through general trade practice. While it is more convenient for consumers to make value comparisons 

when the PDP of the packages are displayed, regulation does not require it. 

In the OWM training classes, we explain that if an inspector encounters packages on shelves where the PDP is “not 

displayed” to consumers, the package is not in violation of the UPLR provided the inspector verifies the manufacturer 

or packer has placed the net quantity and identity information on the panel “most likely” to be displayed, presented, 

shown, or examined under normal and customary conditions of display and purchase.

Part 2. Principal Display Panel Requirements

A separate, but related labeling issue arises when an inspector finds packages that have the Principal Display Panel 

(PDP) on the back or bottom of a package or container (see Figures 5(a), 5(b), and 6). When this is found, the inspector 

Figure 3. Properly labeled packages displayed 

in a case with several PDPs not visible.

Figure 4. Properly labeled cereal packages 

displayed on a shelf with several PDPs not 

visible.

BOTH 

METHODS OF 

DISPLAYING 

PACKAGES ARE 

PERMISSIBLE
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Weights and Measures Connection, Vol. 8, Issue 4 Page 3

should inspect the package to determine if it is labeled with the identity, quantity, and responsibility information as 

required by the UPLR in NIST Handbook 130. 

Brief Overview of the PDP Requirements.

WHAT IS A PRINCIPAL DISPLAY PANEL (PDP)?

The “PDP” is that part, or those parts of a label that is, or are “most likely” to be displayed, presented, shown, or 

examined under normal and customary conditions of display for retail sale. The PDP is defined in Section 2.7. of the 

UPLR in NIST HB 130 (this definition is consistent with the requirements of the Federal Fair Packaging and Labeling 

Act and the Food Drug and Cosmetic Act.) 

The UPLR requires that the identity of the product and the net quantity of contents of the package be shown on the 

PDP in conspicuous type sizes and styles in colors that contrast with the background to allow consumers to find the 

information quickly and easily to facilitate value comparison. It is the manufacturer or packager of the product that 

determines which panel or panels of the package is to be the PDP. 

CAN THE PACKER OR MANUFACTURER USE THE BOTTOM OR BACK OF A PACKAGE AS THE PDP?

Figure 5(a). 

Figure 5(b). 

Figure 6. This is a retail display of 

packages of produce where the PDP is 

placed on the back or bottom of the 

container. (The inspector displays a 

package at left that shows the PDP

label on the back.)

THE PDPs IN FIGURES 5(a), 5(b), 

AND 6 ARE NOT ON THE PANEL 

OF THE PACKAGE “MOST LIKELY” 

TO BE DISPLAYED. THE PACKAGE 

LABELING DOES NOT COMPLY 

WITH THE UPLR.
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Weights and Measures Connection, Vol. 8, Issue 4 Page 4

No. The UPLR requirements ensure that consumers are informed of what and how much they are going to buy when 

they purchase packaged goods. When a package complies with the UPLR, it is not necessary for the consumer to 

search all over the package for the required information to make an informed purchasing decision. Most packages are 

“designed” to be displayed with the PDP upright and in a forward-facing position under “normal” and “customary” 

conditions. The back or bottom of the package are not considered “most likely” to be viewable. 

For this reason, placing the product identity and net quantity of contents on the bottom or backside of a container does 

not comply with the requirement that the PDP be that part of the package label “most likely” to normally or customarily 

be displayed, presented, or shown to consumers on a retail display. However, a manufacturer may design a package 

that includes multiple PDPs to allow retailers to display the packages in different orientations. 

WHY DO RETAILERS PLACE THE PDP AND UPC BARCODE ON THE BOTTOM OF A PACKAGE?

You will find that retailers sometimes affix a random weight label that includes the UPC barcode and the PDP with 

the required information (i.e., identity, net quantity) to the bottom of a package. This often occurs on packages 

containing iced birthday cakes, pies, and other fragile goods packaged in store that may be damaged if turned upside 

down. The primary reason for the placement of the UPC barcode on the bottom of the package is so a checkout clerk 

does not have to turn the package over to scan the UPC barcode at checkout. While this approach lessens the chance 

that an iced birthday cake will be damaged it can be difficult for the consumer to find the product identity, net weight, 

and price information. 

Even in this situation, there is no justification for the PDP to be on the bottom of the package (because, as explained 

above, the bottom of a package is not the panel “most likely” to be displayed). If this labeling approach is used, 

retailers should, at a minimum, affix a duplicate label on top of these packages as a customer service to allow easy 

access to the required net quantity and product identity information. The “dual” label solution addresses the issue of 

label placement on “fragile” products where the store’s scanner only reads from the bottom. In many stores, retailers 

have moved beyond the need to use duplicate labels and instead they use “wraparound” labels as shown below (see 

Figure 7 and 8). 

One practical solution is for the retailer to use a single long label that reaches from the top of the package, where the 

PDP shows the product identity and net quantity, around the side of the package and over the bottom where the UPC 

scan bars are presented for scanning (see Figures 7 and 8).

Wrap Around Label on “Fragile” Product

Figure 7. The picture above shows a “fragile” product (i.e., those products that would become damaged if 

turned over). In this example, the retailer places a “wraparound label on the product that places the identity, 

net weights, and price information on the top of the package for easy access and “wraps the label onto the 

bottom where the UPC barcode is accessible without turning the package over when scanned.
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Weights and Measures Connection, Vol. 8, Issue 4 Page 5

In summary, the UPLR does not apply to the display of packages in retail stores but does apply to labeling violations 

in cases where it is determined that the PDP is not on the panel “most likely” to be displayed. 

Please contact David Sefcik at david.sefcik@nist.gov or at (301) 975-4868 or Lisa Warfield at 

lisa.warfield@nist.gov or at (301) 975-3308 for additional assistance and information.

Figure 8. An iced cake with a wraparound label showing the PDP on top of the package 

with identity, price, and net weight and the UPC on the package bottom for scanning. 

Inspectors can recommend that retailers found placing the PDP label on the bottom or 

back of packages consider using the wraparound label as a suitable alternative.