Microstructured Taggants refers to a method of manufacturing precisely formed taggant materials or particles of uniform size and information content - preferably formed from polymeric, protein, or carbohydrate materials. Specific combinations of shape, size, color, reflectivity, refractive index, surface geometry, imprinting, optical effect, and electromagnetic properties can be used to uniquely tag manufactured articles.

The range of applications for taggant particles according to this invention is nearly boundless. These taggants can be incorporated into inks for printing secure, counterfeit-resistant, authenticatable currency, identification cards, financial transaction cards, vital records, and other high-security, high- value documents. The taggant particles can, alternatively or additionally, be incorporated into the paper and polymer substrates these documents are printed on. Such tagged materials can be used as labels for lot tracking, tamper prevention and indication, product authentication, covert bar coding, and distributed packetized authentication information.