Abstract: Resin based, film-forming compositions such as adhesives are coded for identification by dispersing insoluble fluorescent taggant particles within the resin phase of the composition. The taggant is readily identifiable even after long term storage or service on a floor or wall by peeling away the floor covering such as carpet and examining a sample of the layer of adhesive under fluorescent light to determine the pattern size and color of the taggant particles. If the particles are not readily visible, the sample can be scraped with a sharp instrument such as a putty knife to expose the taggants. If the particles are still not visible, the sample is dissolved in a heavy solvent for the resin binder and the taggant particles will often float to the top where they can be observed for size and color. Failing this, the solution and residue can be separated by filltration whereby the taggants are easily detected.