Abstract: A method of modifying the magnetic properties of a thin film of a magnetically active material is provided which comprises forming surface modulations on the material in order to partition it into regions which display at least some degree of mutual magnetic independence. The resulting modified thin film may be used as a marker or tag in an anti-pilferage or article location system. The surface modulations formed on the material in the anti-pilferage or article location marker serve to enhance the response of the marker when used in an anti-pilferage or article location system.

Abstract: Magnetic devices are disclosed which include an article comprising a substrate and a thin coating of a magnetic material, in which:(a) said substrate is a flexible, laminar material; (b) said magnetic material is an amorphous metal glass of high intrinsic magnetic permeability, with low or substantially zero magnetostriction, and with low coercivity; and (c) said thin coating of a magnetic material is not greater than 6 microns in thickness. This article can be used as, or to make, an antipilferage tag or marker. Deactivation materials and configurations are also disclosed, as well as techniques, in particular sputtering or PVD, for producing such a tag.

Abstract: This application discloses a method of recognizing and/or locating preselected categories of articles, which comprises applying to the articles a plurality of magnetic elements in predetermined associations (e.g. with predetermined numbers of magnetic elements and with predetermined spacings between said elements), whereby when the articles are caused to move relative to a predetermined interrogating magnetic field, each particular association of magnetic elements gives rise to a magnetic signature whereby the article or category of article carrying each of the predetermined associations can be recognized and/or located. A series of tags or markers for use in such a method, as well as a system for determining the location and/or identity of an article within an article conveying network, are also disclosed.