Many of us have seen large ink tags on items of clothing in the store, and know better than to tamper with them. Few people know how they actually work, or what is the point of ink tags in store security for shoplifting reduction.
Ink tags are rarely connected to any kind of alarm system, often because they don't need to be. The kind of ink tags placed on clothing items function similar to a monarch butterfly's visual system of defense. They discourage theft through splashy bright warnings painted on the tag itself.
Ink tags also can be very large and heavy devices. This is another visual warning to the would-be shoplifter that re-selling this item with the tags is impossible. Vitag, a company that makes and sells ink tags, calls this "benefit denial" security. The size of some ink tags also makes it difficult to conceal items while attempting to steal them.
Ink tags warn that tampering with the tag will result in indelible ink soiling the garment, and the tamperer's hands. This is a warning to shoplifters that their stolen merchandise can neither be worn nor sold.
Ink tags consist of two pieces held together by a narrow pin. The pin goes through the item of clothing and secures the two pieces together. The only way to get a tag off once the two pieces are secure, is with a special removal device, which detaches the two pieces without disrupting the ink inside.
The ink is stored in one to three vials inside the tag--depending upon the size. When the joining pin is forcibly pulled, which is the only way to remove the tag at home, the ink vials shatter, and the garment is ruined, rendering it useless to the shoplifter.