Is That a Genuine UL Mark or a Counterfeit?

July 7, 2009
There are several tell-tale signs that reveal if a UL symbol is genuine or not.

The century old symbol of the Underwriters Laboratories, the UL Mark, is a well-known sign to consumers that a product has been honestly tested and approved as safe for its intended use. Some unscrupulous manufacturers and marketers, however, put bogus UL symbols on products that have been nowhere near the Underwriters lab. To stem the tide of counterfeit UL marks, CableOrganizer.com, a firm that sells electrical cable and wiring, published guidelines to help users tell the difference between genuine and false marks.

Genuine UL marks, whether die-stamped, silk-screened, or molded onto a product or printed on a label must have the following four design elements to be verified as legitimate:
— The letters UL arranged diagonally (descending left to right) within a circle with a small ® directly below the U.
— The word “LISTED” in all capital letters below or beside the circle.
— A four-character alphanumeric control code or a four to six-digit issue number. The issue number may or may not be preceded by the phrase “Issue No.” as well as one or two letters. — An identity phrase that correctly names the product.

Other items found on legitimate UL marks include a UL file number (which often have “E” as a prefix), the manufacture’s name or logo, applicable electrical ratings, and the products catalog, model or type designation. Counterfeit UL marks often carry the following red flags:
— Packaging references UL but carries no markings or other UL designations.
— Letters UL printed side by side.
— Words such as “approved” or “pending” appear instead of “classified” or “listed.”
— Product package contains many spelling and grammatical errors.
— No documentation such as instructions for use, safety warnings, or care and maintenance data.
— Package lacks toll-free customer service number, company address, or other company contact information.

And the places you are most likely to see counterfeit UL markings are on products found at deep discount stores, flea markets, street vendors, and other temporary retail outlets.

Sponsored Recommendations

Sept. 16, 2025
From robotic arms to high-speed conveyors, accuracy matters. Discover how encoders transform motor control by turning motion into real-time datadelivering tighter speed control...
Sept. 16, 2025
Keep high-torque gearboxes running efficiently with external lubrication and cooling systems delivered fast. Flexible configurations, sensor-ready monitoring, and stocked options...
Sept. 16, 2025
Now assembled in the U.S., compact P2.e planetary gear units combine maximum torque, thermal efficiency, and flexible configurations for heavy-duty applicationsavailable faster...
Aug. 22, 2025
Discover how to meet growing customer demands for custom products without overextending your engineering team. Learn how scaling your automation strategy can help you win more...

Voice your opinion!

To join the conversation, and become an exclusive member of Machine Design, create an account today!