A yarn-based coding system that can be used to track textiles through the supply chain has been developed by Swedish researchers. The yarns function as an optical stamp on the surface of woven or knitted fabrics that is introduced during the weaving process and unlike other technologies such as RFID tags or barcodes is an intrinsic part of the textile product and cannot be removed. The yarns are coded using twist-based optical features which can be generated on a hollow spindle frame.

Since the reproduction of these tags is not easy like other tags, including barcodes and RFIDs, they can provide enhanced security to textile products from counterfeits. Further, from the economic aspect, yarn-based tags are normal textiles, therefore, there is no need of special material components and in-house production in a textile industry can be done.

In contrast barcodes and RFIDs possess low security against copying and reproduction, which means an identical tag can be easily reproduced and placed with a counterfeit product. Further, these tags are generally removed at the point of sale, so it becomes difficult to track the history of a product back thereafter, while embedded foreign materials such as tracking chips can raise privacy issues and cause problems with recycling.