EcommerceBytes-Update, Number 356 - April 06, 2014 - ISSN 1528-6703     4 of 6

What Online Merchants Should Know about Unique Product Identifiers

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Online sellers quickly learn the importance of Unique Product Identifiers such as UPCs when researching products, listing them for sale and submitting feeds to search engines. Often extremely helpful, Unique Product Identifiers can also present hurdles.

Such is the case when trying to list an item for sale on a marketplace like, when another seller has incorrectly listed an item under the UPC for your product, or when another seller lists the same product as yours but has used an incorrect UPC. Thanks to Amazon's catalog where each product must have a unique product identifier, it can make the difference in whether your product displays the correct photo and specs to potential buyers.

Amazon, eBay, Google and other ecommerce giants are recognizing the value of making sure products are aligned with the right information based on a unique identifier, according to GS1 US, and it's in a position to know. GS1 US is a member of GS1, a global information standards organization with more than 110 member organizations around the world. The organization says correct usage of UPCs and GTINs (Global Trade Item Numbers) make it easier for consumers to find the products they are looking for online.

EcommerceBytes interviewed Bernie Hogan, Senior Vice President of Emerging Capabilities and Industries at GS1 US, to learn what online sellers should know about UPC codes when listing products online.

EcommerceBytes: What are UPC codes?

Bernie Hogan: A Universal Product Code (UPC) is a series of numbers used in barcodes to uniquely identify products and are also commonly called Global Trade Item Numbers (GTINs). In its most common form, a UPC is 12 digits long. UPC barcodes ensure that all products are properly identified at any retail point of sale, speed up data collection, and result in more accurate exchange of data between trading partners.

EcommerceBytes: Where can manufacturers/creators obtain UPC codes, and are you the only provider?

Bernie Hogan: GS1 US is the only organization authorized to license company identification numbers called Company Prefixes in the US. GS1 US licenses Company Prefixes to enable organizations to create UPCs/GTINs for their products. As their businesses expand and grow, they can use the GS1 Company Prefixes to create additional UPCs/GTINs to identify their products - that can be used in the US and globally. When businesses license a GS1 Company Prefix from GS1 US, they are making a short-term and long-term investment in their business. Businesses can obtain a company prefix at

EcommerceBytes: What should sellers know about UPCs when listing products online?

Bernie Hogan: Inconsistent or incorrect usage of UPCs/GTINs make finding and discovering products online difficult for consumers. Increasingly, online retailers and platforms are recognizing the problems created by improper UPC usage and are working to address the challenges. Many more online retailers and platforms now understand that the GS1 US framework, which was developed based on 40 years of experience in identifying products in the brick and mortar space, is equally useful to identify products and share information online.

Businesses have utilized GS1 Standards for decades building a globally deployed and proven system for product identification. Leveraging and extending this investment in response to the rising consumer demand for accurate online product data is a logical choice for businesses that want to grow and achieve greater efficiencies.

EcommerceBytes: If a seller is uncertain of a product's UPC code, how can they find it?

Bernie Hogan: They can visit a GS1 US resource called GEPIR, which stands for Global Electronic Party Information Registry. It provides access to basic information for companies that licensed Company Prefixes from GS1 US. By simply typing a product bar code number into GEPIR, anyone can find the manufacturer/seller of a product. Company names can also be used as search criteria.

EcommerceBytes: If a seller bundles two different products together, they'll need a UPC code for a marketplace like Amazon. They are not the manufacturer. Do you recommend they obtain a UPC code from GS1 US for that new listing?

Bernie Hogan: Sellers/merchants can obtain a UPC from GS1 US for the bundled product listing for Product X, as long as it's in compliance with a website like Amazon's specific guidelines.

For example, Amazon states in its bundling policy that if the product is a multi-pack of the same product (a 3-pack of AA batteries, for example), or if it is a variation on the original product (a size small, medium or large shirt), it is not a bundled product. This is similar to how UPCs/GTINs work in general. Different quantities of the same product do not need their own unique identification number.

But a seller may bundle together a yoga mat, a yoga DVD and a yoga book, for example, and by Amazon's requirements, this is now a different product and needs its own UPC/GTIN. eBay also requires bundled products to be listed in their catalog with certain product details, the product UPC included.

GS1 US provides members who are brand owners (a.k.a. organizations that own the trade item specifications, including manufacturers, retailers, wholesalers, distributors) the ability to create UPCs/GTINs for bundled products. More information about how this works is available in our GTIN Allocation Rules document.

Please note that the GTIN Allocation Rules document is in the process of being updated - GS1 has promised to provide a link to the new document as soon as it becomes available.

EcommerceBytes: Does GS1 US work with to help them with their product catalog or to verify UPC codes?

Bernie Hogan: GS1 US is actively engaged with both traditional brick and mortar retailers and online commerce platforms in a harmonized way to extend GS1 Standards into the online world - we see it as the next logical step for the future of ecommerce.

Late last year, we also welcomed the general manager of structured data of eBay, Amit Menipaz, to our Board of Governors who will help us better understand the needs of the digital marketplace and participate in fulfilling our vision. In addition to working with e-tailers and retailers, GS1 US also collaborates with ecommerce platform providers, solution providers, content aggregators and distributors.

EcommerceBytes: Some sellers say if they encounter a product page on that contains errors, they'll create a new page for the product using a different UPC. Any thoughts on that?

Bernie Hogan: Inconsistent and incorrect usage of UPCs/GTINs makes finding and discovering products online difficult for the consumer. When it comes to meeting consumer expectations, the stakes for all online retailers, e-tailers and solution providers have never been higher.

Better product identification based on accurate usage of the GS1 system will allow customers to discover and purchase the products they want, wherever they are - at home, in store or on the move, which leads to increased sales and brand loyalty. GS1 US will soon be releasing a guideline this year that will help businesses find and resolve incorrect, duplicate or conflicting product identification. This will help companies respond to requests from retailers who have stated to sellers that duplicate listings caused by missing or invalid UPCs/GTIN codes make it more difficult for customers to find, evaluate and purchase products.

EcommerceBytes: What should sellers know about UPC resellers?

Bernie Hogan: As the retail marketplace undergoes significant transformation, we've become more aware of inconsistencies in UPCs/GTINs due to error or unauthorized numbers being sold through channels other than GS1 US.

Errors and inconsistencies can be avoided by working within the GS1 System of Standards - some retailers request adherence to these standards.

When a company today becomes a member of GS1 US, it's assigned a GS1 Company Prefix identification number that is globally unique and reserved for use by that company. The company incorporates their GS1 Company Prefix in their product identification numbers/GTINs for use in barcodes and online.

Resellers allow multiple companies to use the same GS1 Company Prefix, which is contrary to the most fundamental principle of the GS1 numbering system. From the beginning, GS1 Company Prefixes were designed to identify only one company.

Also, a company that wants to grow or decides to make modifications to a product will need more UPCs/GTINs to uniquely identify each new version of the product. With a GS1 Company Prefix, a company can create as few as 10 unique items and as many as 100,000 unique items. Details about pricing are located on the GS1 US website. With the GS1 Company Prefix, companies can generate UPCs/GTINs (or other types of barcodes) to keep up with business expansion and be assured that their barcodes will be accepted by retailers globally.

EcommerceBytes: What could marketplaces do to do a better job at ensuring accurate UPC codes?

Bernie Hogan: Leveraging the GS1 System of Standards helps make marketplaces more conducive to the discovery and purchase of products. GS1 Standards have benefited brick-and-mortar for decades and empower business to create a unique, accurate identity for every product. That identity travels the entire journey from the factory to the consumer, improving logistics, marketing, online search and safety. As a result, consumers find and purchase more of the products they want and trading partners boost efficiency and revenue.

Article updated for clarification on 4/7/14.

About the author:

Ina Steiner is co-founder and Editor of EcommerceBytes and has been reporting on ecommerce since 1999. She's a widely cited authority on marketplace selling and is author of "Turn eBay Data Into Dollars" (McGraw-Hill 2006). Her blog was featured in the book, "Blogging Heroes" (Wiley 2008). Follow her on Twitter at @ecommercebytes and send news tips to

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