A method for securely sharing validation information of one or more data files stored on different cloud servers using distributed ledger technology, the method comprising: a) requesting access to the data files of a user stored on the cloud servers, wherein the data files are requested by a company registered to a main blockchain to secure a Know Your Customer, KYC, process in response to a request from the user to enter into a contract with the company; b) calculating, by the company, a hash of the data files; c) constructing, by the company, a structured Merkle tree using the hash of the data files and additional hashes received from the user, the additional hashes being hashes of other data files for which the user has not granted access, but has used to construct a corresponding Merkle tree for which the user has committed a root value to the main blockchain to which the user has registered; d) checking, by the company, whether the root value of the Merkle tree constructed in step c) is the same as the one the user has committed to the main blockchain; e) checking, by the company, whether the hash of the data files is stored in a block of a satellite blockchain linked to the main blockchain and operated by a subset of nodes of the main blockchain that trust one another; f) based on a determination in step e) that the hash of the data files is already stored in the satellite blockchain, validating, by the company, the data files without undergoing any other validation process, and based on a determination in step e) that the hash of the data files is not already stored in the satellite blockchain or in a different satellite chain linked to the main blockchain, performing a separate validation process, and then issuing, by the company, a transaction in a new block on the satellite blockchain including the hash of the data files; and g) issuing, by the company, the contract once the data files have been validated. a) requesting access to the data files of a user stored on the cloud servers, wherein the data files are requested by a company registered to a main blockchain to secure a Know Your Customer, KYC, process in response to a request from the user to enter into a contract with the company; b) calculating, by the company, a hash of the data files; c) constructing, by the company, a structured Merkle tree using the hash of the data files and additional hashes received from the user, the additional hashes being hashes of other data files for which the user has not granted access, but has used to construct a corresponding Merkle tree for which the user has committed a root value to the main blockchain to which the user has registered; d) checking, by the company, whether the root value of the Merkle tree constructed in step c) is the same as the one the user has committed to the main blockchain; e) checking, by the company, whether the hash of the data files is stored in a block of a satellite blockchain linked to the main blockchain and operated by a subset of nodes of the main blockchain that trust one another; f) based on a determination in step e) that the hash of the data files is already stored in the satellite blockchain, validating, by the company, the data files without undergoing any other validation process, and based on a determination in step e) that the hash of the data files is not already stored in the satellite blockchain or in a different satellite chain linked to the main blockchain, performing a separate validation process, and then issuing, by the company, a transaction in a new block on the satellite blockchain including the hash of the data files; and g) issuing, by the company, the contract once the data files have been validated.