A user instrument for engaging in a transaction includes a graphically encoded icon having a static portion, and an intrinsic portion comprising an area of stimuli-responsive material defining a first machine-readable indicia. At least a portion of the stimuli-responsive material transforms from a first state to a second state in response to a trigger. The transformation from the first state to the second state of the portion of the stimuli-response material results in a second machine-readable indicia. The transformation of the stimuli-responsive material from the first state to the second state is semi-irreversible. The second machine-readable indicia comprises information to permit or deny the user to engage in a second transaction via the user instrument.

A security device and a method for verifying such a security device are disclosed. The security device has at least two security features. At least one of the security features is a tamper-evident security feature, which is configured to alter irreversibly upon mechanical tampering with the security device. At least one other of the security features is a robust security feature, which is robust against tampering with the security device. The at least two security features can be extracted from at least one image of the security device with a programmable device having a camera at least in an intact state of the security device.

Tamper-proofing and secure identity validation techniques in a transaction processing system and secure electronic payment techniques are disclosed. A tamper-proof transaction processing device is provided and comprises at least two different strength adhesives to secure parts of the device together and a housing comprising at least a first and second protective layer. An electronic component comprising a secure element chip storing unique information relating to the chip is located between the first and second protective layer in the housing. In another aspect, a transaction processing system includes a payment instrument that is configured to approve only negative value and/or zero value transaction requests. Another aspect provides an identity card checking system and method where the identity card is brought into proximity of a data processing device and identity information is displayed on the screen of the data processing device for the period of time while the card is in proximity.

Tamper-proofing and secure identity validation techniques in a transaction processing system and secure electronic payment techniques are disclosed. A tamper-proof transaction processing device is provided and comprises at least two different strength adhesives to secure parts of the device together and a housing comprising at least a first and second protective layer. An electronic component comprising a secure element chip storing unique information relating to the chip is located between the first and second protective layer in the housing. In another aspect, a transaction processing system includes a payment instrument that is configured to approve only negative value and/or zero value transaction requests. Another aspect provides an identity card checking system and method where the identity card is brought into proximity of a data processing device and identity information is displayed on the screen of the data processing device for the period of time while the card is in proximity.

Systems and methods are provided for decoding secure tags using an authentication server and secure tag reader. The system can include at least one processor and at least one non-transitory memory. The memory can contain instructions that, when executed by the at least one processor, cause the secure tag reader to perform operations. The operations can include detecting a potential secure tag in an image and generating a normalized secure tag image using the image and a stylesheet. The operations can further include providing an identification request to an authentication server, the identification request including the normalized secure tag image. The operations can additionally include receiving rules for decoding tag data encoded into the secure tag as tag feature options and decoding the tag data using the received rules.

Systems and methods are provided for decoding secure tags using an authentication server and secure tag reader. The system can include at least one processor and at least one non-transitory memory. The memory can contain instructions that, when executed by the at least one processor, cause the secure tag reader to perform operations. The operations can include detecting a potential secure tag in an image and generating a normalized secure tag image using the image and a stylesheet. The operations can further include providing an identification request to an authentication server, the identification request including the normalized secure tag image. The operations can additionally include receiving rules for decoding tag data encoded into the secure tag as tag feature options and decoding the tag data using the received rules.

Tamper-proofing and secure identity validation techniques in a transaction processing system and secure electronic payment techniques are disclosed. A tamper-proof transaction processing device is provided and comprises at least two different strength adhesives to secure parts of the device together and a housing comprising at least a first and second protective layer. An electronic component comprising a secure element chip storing unique information relating to the chip is located between the first and second protective layer in the housing. In another aspect, a transaction processing system includes a payment instrument that is configured to approve only negative value and/or zero value transaction requests. Another aspect provides an identity card checking system and method where the identity card is brought into proximity of a data processing device and identity information is displayed on the screen of the data processing device for the period of time while the card is in proximity.

Tamper-proofing and secure identity validation techniques in a transaction processing system and secure electronic payment techniques are disclosed. A tamper-proof transaction processing device is provided and comprises at least two different strength adhesives to secure parts of the device together and a housing comprising at least a first and second protective layer. An electronic component comprising a secure element chip storing unique information relating to the chip is located between the first and second protective layer in the housing. In another aspect, a transaction processing system includes a payment instrument that is configured to approve only negative value and/or zero value transaction requests. Another aspect provides an identity card checking system and method where the identity card is brought into proximity of a data processing device and identity information is displayed on the screen of the data processing device for the period of time while the card is in proximity.

Sheet-like product and method for authenticating a security tag including a section of the sheet-like product. The sheet-like product includes at least one security feature having optical properties that change with the viewing angle and, and at least one marker, wherein each marker is uniquely attributable to a position on the sheet-like product. The position of the at least one security feature on the sheet-like product is predetermined relative to the position of the at least one marker on the sheet-like product.

Sheet-like product and method for authenticating a security tag including a section of the sheet-like product. The sheet-like product includes at least one security feature having optical properties that change with the viewing angle and, and at least one marker, wherein each marker is uniquely attributable to a position on the sheet-like product. The position of the at least one security feature on the sheet-like product is predetermined relative to the position of the at least one marker on the sheet-like product.