Chapter 26: Retail - The Missed Opportunity |
Summary |
Unlike UPC, Code 39 was never adopted for point-of-sale due to its low density it couldn't fit a 12-digit product code on a small gum package. This chapter explains why Code 39 lost the retail battle, while simultaneously becoming the backbone of dozens of other industries. The same technical characteristics that disqualified it from grocery checkout variable length, alphanumeric support, lack of a mandatory check digit, and forgiving print tolerances made it invaluable for inventory management, defense logistics, automotive production, healthcare tracking, and countless other applications. Code 39 succeeded everywhere except the cash register. |
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The Barcode That Conquered the World (Except the Checkout Lane) |
In 1974, the same year that the first UPC barcode was scanned on a pack of Wrigley's gum in an Ohio supermarket, Dr. David Allais and Ray Stevens of Intermec introduced an entirely different barcode symbology . They called it Code 39 also known as Code 3 of 9, Alpha39, or USD-3 . It was the first barcode symbology capable of encoding not just numbers, but letters as well . This was a revolutionary breakthrough. |
Yet today, if you walk into any grocery store, department store, or convenience store anywhere in the world, you will not find a single Code 39 barcode on a consumer product. The barcodes you see at checkout are UPC (in North America) or EAN (everywhere else). Code 39, despite its historical significance and technical elegance, never made it to the retail point-of-sale. |
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WhyThe answer is simple, and it has everything to do with the physical constraints of product packaging and the relentless economics of retail. |
The core problem was density. Code 39 is what the industry calls a 'low density' symbology . This means that for any given amount of data, a Code 39 barcode must be physically larger than other barcode types. It simply requires more horizontal space to encode the same information. A twelve-digit product code the standard for retail goods would produce a Code 39 symbol too wide to fit on many small items. Consider a single pack of chewing gum, a lipstick tube, or a box of breath mints. These packages have extremely limited real estate. The UPC standard addressed this with UPC-E, a compressed version that could fit on tiny packages by suppressing unnecessary zeros . Code 39 had no such option. |
If you could somehow force a twelve-digit Code 39 symbol onto a pack of gum, the bars would become so narrow that the symbol would be nearly impossible to print reliably and essentially unreadable by the scanners of the era. Low density was the dealbreaker. This single technical limitation sealed Code 39's fate in the retail world. |
There was a second, almost philosophical reason. Code 39 was designed with flexibility in mind. It is a variable-length symbology, meaning it can encode messages of any length five characters, ten characters, fifty characters . That is an advantage in industrial settings where you might need to encode part numbers, serial numbers, or alphanumeric descriptions. But for retail, the fixed-length UPC was simpler and more efficient. A barcode scanner at a grocery store does not need to figure out where the code ends; it always expects exactly twelve digits (or eight digits for small items) . Fixed-length codes allowed for faster scanning and simpler hardware, which was crucial when processing thousands of items per hour. |
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So Code 39 was left out of the retail revolution. But what the retail industry rejected, almost every other industry embraced. |
The Technical Characteristics That Defined Its Fate |
To understand why Code 39 found its true calling outside retail, we need to appreciate its technical architecture. Each character in a Code 39 barcode is composed of nine elements: five bars and four spaces . Exactly three of these nine elements are wide; the remaining six are narrow . This 'three of nine' pattern is where the symbology gets its name. |
The width ratio between narrow and wide elements is remarkably forgiving. It can range anywhere from 1:2 to 1:3 . This tolerance means that Code 39 can be printed on a wide variety of equipment, from high-end industrial printers to basic dot-matrix printers and even standard office laser printers. If you had a printer, you could produce a Code 39 barcode simply by installing a barcode font and typing the data with asterisks on either side . No special software was required. This ease of generation was a huge advantage for businesses that did not want to invest in expensive dedicated barcode printing systems. |
Another key characteristic is that Code 39 does not require a check digit. While the industry later added an optional modulo-43 check digit for certain applications, the basic specification does not mandate one . This is a double-edged sword. On one hand, it simplifies implementation and makes the barcode easier to generate manually. On the other hand, it provides less error protection than symbologies that include a mandatory check digit. However, Code 39 is considered 'self-checking.' Because each character consists of a specific pattern of wide and narrow elements, the odds of a single printing defect or scanning error converting one valid character into another are extremely low . |
Perhaps the most important feature for many applications is its alphanumeric capability. Code 39 supports uppercase letters A through Z, digits 0 through 9, and a handful of special characters: dash, dot, space, dollar sign, slash, plus sign, and percent sign . Later, Code 39 Extended (also known as Full ASCII Code 39) was developed to encode the full 128-character ASCII set by using two-character combinations . This ability to encode letters and numbers is what made Code 39 the darling of industries that needed to track parts, documents, and assets with alphanumeric identifiers. |
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Industry After Industry: The Code 39 Success Story |
Defense and Government: The LOGMARS Mandate |
Perhaps the most significant early adoption of Code 39 came from the United States Department of Defense. In 1981, the DoD adopted Code 39 under a program known as LOGMARS (Logistics Applications of Automated Marking and Reading Symbols) . This decision was monumental. The military required that all inbound materials be marked with Code 39 barcodes . Suppliers had to comply, which meant that thousands of companies across the defense industrial base suddenly needed to print and read Code 39 symbols. |
Why Code 39The military's needs were very different from those of a supermarket. They needed to track parts, equipment, and supplies with alphanumeric serial numbers and part numbers. A typical military part might have a designation like 'A-17-493B' a mix of letters, numbers, and hyphens. UPC could not handle this. Code 39 could. Furthermore, the military valued the symbology's ruggedness and its tolerance for less-than-perfect printing conditions. Equipment in the field might be marked with barcodes printed under harsh conditions, applied to curved surfaces, or exposed to dirt and abrasion. Code 39's wide-narrow ratio flexibility made it more forgiving than denser symbologies. |
The LOGMARS mandate created a cascade effect. As Dr. David Allais later recalled, 'the U.S. military standardized on my Code 39 and required it on all inbound materials. Then, within about two years, companies in the U.S. automotive industry had their own requirements involving Code 39' . The military's stamp of approval gave Code 39 credibility and drove the development of scanners, printers, and software that supported it. Once the infrastructure existed, other industries naturally adopted it. |
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Automotive Manufacturing: Tracking the Supply Chain |
The automotive industry became one of the largest adopters of Code 39. Car manufacturers need to track thousands of individual parts as they move through the supply chain and into assembly plants. A single vehicle consists of tens of thousands of components, each with its own part number, batch number, and supplier information. These identifiers are almost always alphanumeric. A part number like 'BMW-51-11-7-123-456' is not something a numeric-only barcode can encode. |
Code 39 appears on everything in automotive manufacturing: engine components, transmission parts, electrical harnesses, body panels, and interior trim . The barcodes are used to manage inventory, verify shipments, track work-in-progress, and assemble vehicles correctly. When a worker on the assembly line scans a part, the system confirms that the correct component is being installed in the correct vehicle. |
The density limitation that disqualified Code 39 from retail is less of an issue in automotive manufacturing. Parts are generally larger than a pack of gum. There is plenty of space on a transmission casing or an engine block to print a barcode. And the ability to read the barcode from different angles and at varying distances is more important than fitting into a tiny space. |
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Healthcare and Medical Devices: The HIBCC Standard |
The healthcare sector adopted Code 39 through standards established by the Health Industry Business Communications Council (HIBCC). This standard, known as the Health Industry Bar Code (HIBC), uses Code 39 as its primary symbology for labeling medical devices, surgical instruments, and pharmaceutical products . |
Hospitals and medical device manufacturers rely on Code 39 for a critical purpose: ensuring that the right device is used on the right patient at the right time. A surgical implant, for example, will carry a Code 39 barcode that encodes its catalog number, lot number, and expiration date. When the implant is received by the hospital, the barcode is scanned to update inventory records. When it is used in surgery, the barcode is scanned again and recorded in the patient's electronic health record. This creates an auditable chain of custody that is essential for patient safety and regulatory compliance. |
The medical environment demands barcodes that can survive sterilization, cleaning, and handling. Code 39's relative simplicity and tolerance of imperfect printing conditions make it suitable for marking items that must be autoclaved or subjected to harsh chemicals. The barcode may be etched, embossed, or printed with special inks to withstand these conditions. |
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Logistics and Warehousing: The Font-Based Advantage |
In logistics and warehousing, Code 39 has long been a workhorse for inventory management and shipping . The symbology's key advantage in this context is its ability to be generated with a simple barcode font. This is a substantial operational benefit. |
In a warehouse, you might need to generate barcodes for hundreds or thousands of different items. You might need to create a barcode on a shipping label, on a packing slip, on a shelf label, or on a receiving document. With Code 39, you can do this using standard office software and a barcode font installed on your printer. You simply type the data you want to encode, surrounded by asterisks (the start/stop characters), and apply the barcode font . The result is a scannable barcode. |
This is not as easy with other symbologies. Code 128, for instance, requires the generation of a check digit and more complex encoding. While this is easily handled by software, it means you cannot simply 'type' a Code 128 barcode in a word processor. Code 39's 'font-based' approach made it accessible to businesses that did not have specialized barcode software or dedicated barcode printers. |
Another logistics application is the use of Code 39 on shipping documents, such as bills of lading. The 'Pro Number' a unique identifier assigned to each freight shipment is frequently encoded as a Code 39 barcode on shipping paperwork . When the shipment arrives at its destination, the barcode is scanned to confirm delivery and update tracking information. |
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Manufacturing and Assembly: Tracking Work-in-Progress |
Across the manufacturing sector, Code 39 is used to track work-in-progress and manage production workflows . A product moving through a factory might have a Code 39 label that identifies its model, configuration, and current status. Workers at each station scan the barcode to record time spent, materials consumed, and quality checks performed. |
The aerospace industry is a notable example. Aircraft construction involves enormous complexity and stringent safety requirements. Every part that goes into an airplane must be traceable from its origin to its installation. Code 39 is used on components, assemblies, and documentation to maintain this traceability . |
The same principle applies in electronics manufacturing, where printed circuit boards and components are labeled with Code 39 barcodes. The alphanumeric capability of Code 39 allows manufacturers to encode component specifications, production dates, and quality control data directly into the barcode. |
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Inventory and Asset Tracking: The Simple Solution |
Beyond large-scale manufacturing, Code 39 has found a home in countless smaller-scale inventory and asset tracking applications. Schools use it for library management. Small businesses use it for equipment labeling. Industrial facilities use it for asset tracking . |
The appeal is straightforward: Code 39 is easy to generate, easy to read, and widely supported. Almost every barcode scanner in existence can read Code 39. If you need to set up an inventory system without investing heavily in specialized equipment, Code 39 is a reliable choice. You can print labels on an ordinary printer, scan them with an inexpensive scanner, and start tracking your assets. |
Non-Retail Applications: The Common Thread |
Across all these industries, a pattern emerges. Code 39 is used wherever the following conditions apply: |
1. Alphanumeric data is needed Product codes, part numbers, and identifiers often include letters, not just digits. |
2. The barcode does not need to be extremely small The physical items being labeled are large enough to accommodate a Code 39 symbol. |
3. Printing tolerances are moderate Barcodes might be printed on varied surfaces or with varied equipment. |
4. Simplicity and compatibility are valued The lack of a mandatory check digit and the ability to use barcode fonts make Code 39 easy to implement. |
5. The application is internal or B2B rather than consumer-facing The barcode is used for logistics, manufacturing, or inventory management, not for point-of-sale scanning by consumers. |
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The Retail Counterfactual |
It is fascinating to imagine what might have happened if Code 39 had been just a little denser. If the designers had chosen a different encoding scheme perhaps with fewer wide elements or a different pattern Code 39 might have been the standard for retail barcodes. A denser Code 39 might have beaten UPC to market, or at least competed with it. |
But the history of technology is full of such forks in the road. UPC and EAN were designed specifically for retail, from the ground up. They were optimized for numeric data, fixed length, and high density. They were standardized by GS1 (then the Uniform Code Council) and became the universal language of retail barcoding . The density requirement was non-negotiable because the economics of retail depend on scanning speed and the ability to label even the smallest products. |
Code 39, by contrast, was designed for general-purpose use. It was a 'swiss army knife' barcode, and as such, it was not the best tool for any single job, but it was good enough for many. In the end, that is exactly what it became: the barcode that works well enough for thousands of applications, but not quite well enough for the world's cash registers. |
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The Legacy of the Missed Opportunity |
When we say that retail was a 'missed opportunity' for Code 39, we mean that the symbology did not capture the most visible and lucrative market for barcodes. Retail barcodes are scanned billions of times per day, everywhere from supermarkets to online order fulfillment centers. They are the face of barcode technology to the public. When people think of barcodes, they think of the black and white stripes on products. Those stripes are almost never Code 39. |
But the missed retail opportunity was, in a sense, a gain for everyone else. By not being tied to the rigid requirements of retail point-of-sale, Code 39 remained flexible and adaptable. It evolved. It spread. It became the default choice for defense, automotive, healthcare, logistics, and manufacturing. |
Today, Code 39 is still widely used, decades after its introduction . It is not a failed symbology. It is a hugely successful one that simply found its niche outside the grocery store checkout lane. The retail market rejected it; countless other industries embraced it. |
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Detailed Summary |
This chapter has explored why Code 39, despite being the first widely adopted alphanumeric barcode and a technical milestone in automatic identification, never achieved success in retail point-of-sale applications. The central obstacle was its low information density, which required a Code 39 barcode to be physically too large for the small packages typical of retail goods. A twelve-digit product code would not fit on a pack of gum, a tube of lipstick, or a candy bar wrapper, making the symbology impractical for consumer products sold through traditional retail channels. This limitation was decisive, as the retail industry requires a barcode that can be printed reliably in a small footprint and scanned quickly at checkout. |
The technical characteristics that disqualified Code 39 from retail were precisely the same characteristics that made it indispensable across a wide range of other industries. The ability to encode alphanumeric characters (A-Z, 0-9, and symbols) allowed Code 39 to represent product identifiers, part numbers, serial numbers, and other inventory codes that include letters, which numeric-only UPC and EAN could not handle. The variable-length design gave users flexibility to encode messages of any length, accommodating everything from a simple part number to a more complex data string that could include batch numbers, production dates, or quantity information. The forgiving print tolerances, with a wide-to-narrow ratio that could range from 1:2 to 1:3, meant Code 39 could be printed on a wide variety of equipment under varying conditions. The lack of a mandatory check digit simplified implementation and allowed Code 39 to be generated with simple barcode fonts, requiring no special software or hardware beyond a standard printer and a font installation. The self-checking nature of each character provided a basic level of error resistance that was sufficient for many applications, and the wide availability of support across barcode readers made Code 39 a safe choice for organizations investing in barcode systems. |
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The adoption of Code 39 spread across numerous sectors through a combination of military mandates, industry standards, and organic growth. The U.S. Department of Defense mandated Code 39 for all inbound materials through the LOGMARS program in 1981, creating a compliance requirement that forced thousands of suppliers to adopt the symbology and driving the development of supporting hardware and software. The automotive industry followed, establishing its own requirements that extended Code 39 usage throughout the supply chain for component tracking and assembly verification. The healthcare sector adopted Code 39 through the HIBCC standard for labeling medical devices, surgical instruments, and pharmaceutical products, using the barcode for patient safety, inventory management, and regulatory compliance. The logistics and warehousing industry embraced Code 39 for its font-based printing capability, allowing shipping labels, packing slips, and receiving documents to carry barcodes generated with standard office printing equipment without specialized hardware. Manufacturing and assembly operations across aerospace, electronics, and general industry use Code 39 to track work-in-progress, manage production processes, and maintain traceability of components and subassemblies. Schools, libraries, small businesses, and industrial facilities have adopted Code 39 for asset tracking, equipment labeling, and inventory management because of its simplicity, low cost of implementation, and universal scanner compatibility. |
The retail point-of-sale, however, remained closed to Code 39. The density limitation was ultimately a fatal flaw for any symbology seeking to serve the mass consumer market. The retail industry's demand for high-density barcodes that could fit on the smallest packages while scanning reliably at high speed was best served by UPC and EAN, which were specifically designed for this purpose. Code 39's developers had aimed for versatility and general-purpose utility, and in doing so, created a symbology that excelled in the broad middle ground of industrial and commercial applications but could not meet the extreme density demands of the checkout counter. |
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In conclusion, while Code 39 lost the retail battle, it won a much larger war. The missed opportunity at the point-of-sale was compensated by a remarkable and enduring success across the industries that keep the global economy running. Code 39 became the quiet workhorse of defense logistics, automotive manufacturing, healthcare tracking, warehousing, and countless other sectors where alphanumeric identifiers and flexible printing requirements matter more than fitting a barcode on a small package. Its story is a testament to how a technology's true impact can lie not in its most visible application, but in the hidden infrastructure that supports the everyday functioning of industrial and commercial systems. Code 39 remains one of the most important barcode symbologies ever created, not because of what it failed to become, but because of what it succeeded in being: the universal barcode for everyone except the checkout line. |
cs@easiersoft.com