A computer-implemented method of authenticating a product comprises receiving, from a scanner terminal, a query message including a hapto-signature of the product to be authenticated, the hapto-signature including at least one haptic characteristic of the product as scanned by a touch-sensitive surface of the scanner terminal. The method comprises comparing the received hapto-signature against a hapto-signature database comprising a plurality of reference hapto-signatures, each reference hapto-signature having an associated product, to determine whether or not the received hapto-signature matches at least one of the reference hapto-signatures, wherein a determination that the received hapto-signature matches at least one of the reference hapto-signatures indicates that the product is authentic. The method comprises generating and sending a response message indicative of whether or not the received hapto-signature matches at least one of the reference hapto-signature.