Theft defeating improvements for shopping carts

An anti-theft system for a shopping cart having a wheeled base, comprising:

• a rectangular mounting structure including a recessed horizontal surface adapted for supporting an anti-theft apparatus therein to the base of the cart, said mounting structure laterally spanning, and being secured to, the underside of the base of said cart,
• anti-theft apparatus removably carried on the horizontal surface of the mounting structure, said anti-theft apparatus comprising a collapsible front suspension assembly including a housing;
• a first set of casters mounted to said housing, retractable pin elements carried by said housing and engagable with said mounting structure for maintaining said front suspension assembly in an operative mode in which said first set of casters engage a supporting surface, a sensor assembly for detecting an activation signal and actuating said retractable pin elements to cause retraction of said pin elements and render said front suspension assembly inoperative, and
• a second set of casters fixed to said shopping cart base frame for preventing said cart from moving in a linear direction when said front suspension assembly is rendered inoperative.