# US 2019/0172058 A1 · Dynamic security code for a card transaction > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0172058 A1 - Document ID: US20190172058A1 - Status: Published application - Kind: A1 - Application number: 16/322,578 - Filed: 2017-07-27 - Published: 2019-06-06 - Earliest claimed: 2016-08-02 - Assignees: Idemia France - Applicants: Idemia France - Inventors: Emmanuelle DOTTAX; Paul DISCHAMP - Web page: https://patentgrep.com/patent/US20190172058A1 ## CPC - G06Q 20/385: {using an alias or single-use codes} - G06Q 20/3223: {Realising banking transactions through M-devices} - G06Q 20/341: {Active cards, i.e. cards including their own processing means, e.g. including an IC or chip} - G06Q 20/3829: {involving key management} - G06Q 20/4018: {using the card verification value [CVV] associated with the card} - G06Q 20/3265: {characterised by personalisation for use} - G06Q: INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES, NOT OTHERWISE PROVIDED FOR ## Abstract An electronic device generates a dynamic security code for a card transaction, e.g. a card not present transaction. The electronic device receives a user request to generate a dynamic security code. The electronic device sends a time request to a time source and receives a message including a time from the time source. The electronic device determines an authenticity of the message containing the time and computes the dynamic security code based on the time received in the message and a key stored at the electronic device. The electronic device causes the dynamic security code to be displayed on a display of the electronic device. The electronic device may be capable of computing a dynamic security code for a plurality of different cards. The electronic device may be a smart phone, a tablet, or a personal computer. ## Claims ### Claim 1 A method of generating a dynamic security code for a card transaction comprising, at an electronic device (10) separate from the card (35): receiving a user request (82) to generate a dynamic security code; sending a time request (84) to a time source (50) external to the electronic device (10); receiving a message (87) comprising a time from the time source (50); determining (88) an authenticity of the message containing the time; computing (89) the dynamic security code based on the time received in the message and a key (dCVV-key ID) stored at the electronic device (10); and causing (90, 91) the dynamic security code to be displayed on a display (14) of the electronic device. ### Claim 2 (depends on 1) A method according to claim 1 wherein at least one of: computing (89) the dynamic security code; causing (90, 91) the dynamic security code to be displayed; are only performed if the message comprising the time is determined to be authentic. ### Claim 3 (depends on 1) A method according to claim 1 wherein the message (87) comprising the time comprises a Message Authentication Code, MAC, and determining an authenticity of the message comprises: computing a Message Authentication Code at the electronic device using a key (time-key ID) stored at the electronic device; and comparing the computed Message Authentication Code with the Message Authentication Code in the received message. ### Claim 4 (depends on 1) A method according to claim 1, wherein the electronic device stores an identifier (ID) and the method comprises: sending a time request (84) to the time source (50), the time request including the identifier (ID). ### Claim 5 (depends on 1) A method according to claim 1 wherein the message (87) comprising the time comprises a digital signature and determining an authenticity of the message uses a public key of the time source (50). ### Claim 6 (depends on 1) A method according to claim 1, wherein the electronic device is capable of computing (89) a dynamic security code for a plurality of different cards, the electronic device (10) stores a master key, and computing (89) the dynamic security code comprises deriving a key for a selected one of the cards using the master key. ### Claim 7 (depends on 6) A method according to claim 6 wherein computing (89) the dynamic security code comprises deriving a key for a selected one of the cards using the master key and an additional per-card data element received from an authorisation entity (40). ### Claim 8 (depends on 1) A method according to claim 1, wherein the electronic device stores an identifier (ID) and the method comprises an enrolment process of: sending the identifier (ID) to an authorisation entity (40), wherein the identifier (ID) can be used to associate the selected card to the key used to compute the security code. ### Claim 9 (depends on 1) A method according to claim 1, wherein the enrolment process comprises: receiving partial data about cards issued to a user from an authorisation entity; receiving user input selecting at least one of the cards; and sending the identifier (ID) to the authorisation entity (40), wherein the identifier (ID) can be used to associate the selected card to the key used to compute the security code. ### Claim 10 (depends on 1) A method according to claim 1, wherein the electronic device is capable of computing (89) a dynamic security code for a plurality of different cards and the method comprises: causing the electronic device to display an invitation for user input to select one of the plurality of cards; and sending a request (83) to generate a dynamic security code for the selected card. ### Claim 11 (depends on 1) A method according to claim 1, wherein at least the step of computing (89) the dynamic security code based on the time is performed by one of: a secure element on the electronic device; a secure partition of a general purpose processor of the electronic device. ### Claim 12 An electronic device (10) capable of dynamically generating a security code for a card transaction, the electronic device (10) being separate from the card (35), the electronic device (10) comprising: at least one processor (12, 212); storage (24, 214); a display (14); a user input device (13); wherein the at least one processor (12, 212) is configured to: receive a request (83) to generate a dynamic security code; send a time request to a time source external to the electronic device; receive a message (87) comprising a time from the time source; determine (88) an authenticity of the message containing the time; compute (89) the dynamic security code based on the time received in the message and a key (dCVV-key ID) stored at the electronic device; and cause (90, 91) the dynamic security code to be displayed on a display of the electronic device. ### Claim 13 (depends on 12) An electronic device according to claim 12 wherein the at least one processor is configured to only perform at least one of: computing (89) the dynamic security code; causing (90, 91) the dynamic security code to be displayed; if the message comprising the time is determined to be authentic. ### Claim 14 (depends on 12) An electronic device according to claim 12 comprising one a secure element (210) on the electronic device (10) which is configured to compute (89) the dynamic security code; a secure partition of a general purpose processor (12) of the electronic device which is configured to compute (89) the dynamic security code. ### Claim 15 (depends on 1) A method according to claim 1, wherein the electronic device (10) is one of: a smart phone, a tablet, a personal computer. ### Claim 16 (depends on 2) A method according to claim 2, wherein the message comprising the time comprises a Message Authentication Code, MAC, and determining an authenticity of the message comprises: computing a Message Authentication Code at the electronic device using a key stored at the electronic device; and comparing the computed Message Authentication Code with the Message Authentication Code in the received message. ### Claim 17 (depends on 2) A method according to claim 2, wherein the electronic device stores an identifier and the method comprises: sending a time request to the time source, the time request including the identifier. ### Claim 18 (depends on 3) A method according to claim 3, wherein the electronic device stores an identifier and the method comprises: sending a time request to the time source, the time request including the identifier ### Claim 19 (depends on 2) A method according to claim 2, wherein the message comprising the time comprises a digital signature and determining an authenticity of the message uses a public key of the time source. ### Claim 20 (depends on 2) A method according to claim 2, wherein the electronic device is capable of computing a dynamic security code for a plurality of different cards, the electronic device stores a master key, and computing the dynamic security code comprises deriving a key for a selected one of the cards using the master key.