A method of providing access to securely held data is provided. A user interacts with the service provider to obtain access to a service by using a device to provide a digital identifier to the service provider, without the digital identifier being made known to the user. At a later date the user wishes to retrieve securely stored data relating to their use of the service. However, because the user does not know the digital identifier, they are unable to identify themselves to the service provider using the digital identifier. The present disclosure provides a secure method for exchanging private identifiers, which allows the user to identify themselves to the service provider in order to gain access to securely stored data relating to the user's previous use of the service. The user can do this using the device on which the digital identifier is stored, or another device.

Generating a private key recovery seed based on random words extracted from an input memory of a user and using the recovery seed to recover the private key. An input that is related to a specific memory of a user is received. The specific memory was previously entered and used to generate random words that are related to each other by being included in the specific memory. The random words are extracted from the received input. The random words are associated with a first private key recovery mechanism for recovering a private key. The random words are input into the first private key recovery mechanism to generate a recovery seed. The recovery seed is input into a second private key recovery mechanism. The second private key recovery mechanism generates a recovered private key upon performing a recovery operation on the private key recovery seed.

In an example, an ecosystem is disclosed that may facilitate digital exchange of a digital asset stored as a computer executable file. The ecosystem may include a plurality of participant systems, wherein the plurality of participant systems may include at least one of an asset user system, an asset holder system, and an asset mining system. The ecosystem may include an asset wrapper associated with the digital asset and configured in the form of a multi-layered structure and computer-executable document. The ecosystem may include a codec configured as a computer executable file and associated with the asset wrapper, wherein the codec may be executed when an external request for the asset exchange is initiated. The ecosystem may include a blockchain device to execute a blockchain smart contract for the asset exchange, wherein the smart contract is executed against a pre-defined number of right tokens characterizing a specific cryptocurrency-value.

A system and associated methods display on a user device a non-fungible token (NFT) in an application that displays video data. The methods include storing the NFT of a user in a database accessible to the application, associating an ID of the user for the application to the NFT, and receiving a selection of the NFT during use of the application. Upon selection, the selected NFT is provided to the user device for superimposing the selected NFT over the user's face, providing the selected NFT as a background image for the video data on the user device, or both. The user device includes a web application that connects the database to a crypto wallet containing the NFT. The NFT may be processed to crop out the eyes and mouth of the NFT for registration with the user's eyes and mouth when the NFT is superimposed over the user's face.

A method for use with a smart card is provided. The smart card may include a communication interface, a housing, a microprocessor embedded in the housing, a battery for powering the communication interface and the microprocessor, and a nano GPS chip, located within the housing and in electronic communication with the communication interface and the microprocessor. The thickness of the smart card is preferably no greater than 0.8 millimeters (“mm”) and has surface area not greater than 86 mm×54 mm. The method may include determining the location of the smart card in response to a request for a smart card transaction authorization and determining the location of a mobile device associated with a specified user of the smart card. Based on the location of the smart card and the location of the mobile device, the smart card may calculate a location delta between the smart card and the mobile device. If the location delta is greater than or equal to a threshold distance, the smart card may deny the request for smart card transaction authorization.

Computer-implemented methods for locking a blockchain transaction based on undetermined data are described. The invention is implemented using a blockchain network. This may, for example, be the Bitcoin blockchain. A locking node may include a locking script in a blockchain transaction Node to lock a digital asset. The locking script includes a public key for a determined data source and instructions to cause a validating node executing the locking script to verify the source of data provided in an unlocking script by: a) generating a modified public key based on the public key for the determined data source and based on data defined in the unlocking script; and b) evaluating a cryptographic signature in the unlocking script based on the modified public key. The blockchain transaction containing the locking script is sent by the locking node to the blockchain network. The lock may be removed using a cryptographic signature generated from a private key modified based on the data.

The invention provides a method and corresponding system for controlling the generation of a blockchain transaction, and/or the recipient of a transaction output. It can also be used to control and record the ownership of an asset represented on the blockchain without the need for a separate registry of ownership. The ownership and transfers thereof can be handled and recorded without the need for knowledge of the parties involved or their identities. According to one embodiment, the method comprises the steps of identifying at least one transaction (Tx) on a blockchain which comprises: an unspent transaction output (UTXO) relating to a tokenised asset associated with an asset controller; and an input which spends an output from a previous transaction that is locked by a redeem script hash. For each identified transaction (Tx), an incomplete blockchain transaction is generated comprising: a first output comprising a copy of the redeem script hash; and a second output which is modifiable such that only the asset controller is able to specify a recipient for the second output. The incomplete blockchain transaction is communicated to the controller of the asset. The incomplete blockchain transaction is incomplete in that it is missing a required cryptographic signature. Thus, payment of income relating to the asset can be re-directed by the controller to a destination of their choice.

A method for execution by a marketplace server includes detecting fraudulent acquisition of an exchange item by a first computing device, where the exchange item has a static identifier (ID) and a dynamic ID that is generated based on exchange item security parameters associated with the exchange item. The method further includes deactivating the dynamic ID and the exchange item security parameters in response to the detecting fraudulent acquisition, where the static ID of the exchange item remains active and valid. The method further includes generating second exchange item security parameters for the exchange item. The method further includes generating a second dynamic ID based on the second exchange item security parameters, where the second dynamic ID establishes the exchange item for utilization in an exchange item marketplace network. The method further includes updating a record in a marketplace database to include the second dynamic ID.

A computer system includes one or more processors and machine readable storage media coupled to the one or more processors having instructions stored therein that cause the computer system to: receive a request for a dynamic token on behalf of a payor; route the request to a first financial institution; receive a message from a second financial institution including a merchant identifier and the dynamic token having a code comprising account information of the payor; identify the first financial institution based on the code; route the dynamic token and the merchant identifier to the first financial institution; receive the account information of the payor; and route the account information of the payor to the second financial institution to process a payment from an account of the payor to an account of the merchant.

A method of generating a hierarchical deterministic keys portfolio, in particular to sign transactions sent to a blockchain. The generation method includes an initialization phase by an administrator and a phase of setting parameters for at least one user. Private key usage contexts are created from the administrator account, each context specifying conditions for use of the private key in said context. User accounts are also created, each user account being associated with a private key in the tree structure, the private key of said user being obtained from a master private key of the administrator, the usage context to which the user account is attached, and the user's identifier.