# US 2018/0323975 A1 · Creating match cohorts and exchanging protected data using blockchain > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0323975 A1 - Document ID: US20180323975A1 - Status: Published application - Kind: A1 - Application number: 15/586,393 - Filed: 2017-05-04 - Published: 2018-11-08 - Earliest claimed: 2017-05-04 - Assignees: International Business Machines Corporation - Applicants: International Business Machines Corporation - Inventors: Francisco P. Curbera; Yurdaer N. Doganata; Maria Eleftheriou; Mark H. Overman - Web page: https://patentgrep.com/patent/US20180323975A1 ## CPC - H04L 9/3236: {using cryptographic hash functions} - G06F 21/602: {Providing cryptographic facilities or services} - G16H 10/60: for patient-specific data, e.g. for electronic patient records - H04L 9/3239: {involving non-keyed hash functions, e.g. modification detection codes [MDCs], MD5, SHA or RIPEMD} - H04L 63/0428: {wherein the data content is protected, e.g. by encrypting or encapsulating the payload} - H04L 63/20: {for managing network security; network security policies in general (filtering policies H04L63/0227)} - H04L 9/50: {using hash chains, e.g. blockchains or hash trees} - H04L 2209/88: Medical equipments - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - G16H: HEALTHCARE INFORMATICS, i.e. INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR THE HANDLING OR PROCESSING OF MEDICAL OR HEALTHCARE DATA ## Abstract A method, computing system and computer program product are provided. A first entity system that stores sensitive information associated with different entities applies a hash function a portion of the sensitive information to produce hash values. Transaction information pertaining to transactions performed on entity systems are stored within a blockchain database accessible to the entity systems. The transaction information includes hash values corresponding to associated entities from the entity systems. The hash values of the first entity system are compared to the hash values from others of the entity systems to determine entity systems containing information pertaining to same entities. The sensitive information for an entity of the first entity system is exchanged with the determined entity systems containing information for that entity. ## Claims ### Claim 1 A method of exchanging sensitive information among a plurality of entity systems comprising: applying a hash function to a portion of sensitive information of a first entity system to produce hash values; storing transaction information pertaining to transactions performed on the first entity system within a blockchain database accessible to the plurality of entity systems having different information for at least some of the same served entities, wherein the transaction information includes the hash values for the portion of sensitive information, and wherein the blockchain database includes transaction information from the plurality of entity systems including hash values from others of the plurality of entity systems; comparing the hash values of the first entity system to the hash values from the others of the plurality of entity systems to determine entity systems containing information pertaining to the same served entities; and exchanging the sensitive information for common served entities of the first entity system with the determined entity systems containing information for those common served entities. ### Claim 2 (depends on 1) The method of claim 1, wherein the blockchain database further includes encryption parameters for encrypting data to be sent to the plurality of entity systems, and the exchanging the sensitive information comprises: encrypting the sensitive information for the common served entities utilizing the encryption parameters of each of the determined entity systems within the blockchain database, wherein the encryption parameters for a corresponding entity system are associated with a private key limiting decryption to that corresponding entity system; and transmitting the encrypted sensitive information to each of the determined entity systems for decryption via the associated private key. ### Claim 3 (depends on 2) The method of claim 2, further comprising: analyzing the exchanged sensitive information to identify one or more issues triggering an action involving a served entity associated with the sensitive information. ### Claim 4 (depends on 3) The method of claim 3, wherein the blockchain database further includes information from the entity systems pertaining to actions involving the served entity, and the method further comprises: applying a set of rules specifying acceptable actions in the blockchain database to validate requested actions involving the served entity. ### Claim 5 (depends on 4) The method of claim 4, wherein the applying of the set of rules further comprises: honoring a communication request and recording the communication request in the blockchain database when the set of rules is not violated. ### Claim 6 (depends on 1) The method of claim 1, wherein the served entities include patients, and the entity systems include healthcare systems. ### Claim 7 (depends on 1) The method of claim 1, further comprising: updating the determined entity systems in response to additional data being received within a new block added to the blockchain database. ### Claim 8 A first entity system for exchanging sensitive information among a plurality of entity systems, the first entity system comprising: at least one processor; and at least one memory connected to the at least one processor, wherein the at least one processor is configured to perform: applying a hash function to a portion of sensitive information of the first entity system to produce hash values; storing transaction information pertaining to transactions performed on the first entity system within a blockchain database accessible to the plurality of entity systems having different information for at least some of the same served entities, wherein the transaction information includes the hash values for the portion of the sensitive information, and wherein the blockchain database includes transaction information from the plurality of entity systems including hash values from others of the plurality of entity systems; comparing the hash values of the first entity system to the hash values from the others of the plurality of entity systems to determine entity systems containing information pertaining to the same served entities; and exchanging the sensitive information for common served entities of the first entity system with the determined entity systems containing information for those common served entities. ### Claim 9 (depends on 8) The first entity system of claim 8, wherein the blockchain database further includes encryption parameters for encrypting data to be sent to the plurality of entity systems, and the exchanging the sensitive information comprises: encrypting the sensitive information for the common served entities utilizing the encryption parameters of each of the determined entity systems within the blockchain database, wherein the encryption parameters for a corresponding entity system are associated with a private key limiting decryption to that corresponding entity system; and transmitting the encrypted sensitive information to each of the determined entity systems for decryption via the associated private key. ### Claim 10 (depends on 9) The first entity system of claim 9, wherein the at least one processor is further configured to perform: analyzing the exchanged sensitive information to identify one or more issues triggering an action involving a served entity associated with the sensitive information. ### Claim 11 (depends on 10) The first entity system of claim 10, wherein the blockchain database further includes information from the entity systems pertaining to actions involving the served entity, and the at least one processor is further configured to perform: applying a set of rules specifying acceptable actions in the blockchain database to validate requested actions involving the served entity. ### Claim 12 (depends on 11) The first entity system of claim 11, wherein the applying of the set of rules further comprises: honoring a communication request and recording the communication request in the blockchain database when the set of rules is not violated. ### Claim 13 (depends on 8) The first entity system of claim 8, wherein the served entities include patients, and the entity systems include healthcare systems. ### Claim 14 (depends on 8) The first entity system of claim 8, wherein the at least one processor is further configured to perform: updating the determined entity systems in response to additional data being received within a new block added to the blockchain database. ### Claim 15 A computer program product comprising: at least one computer readable storage medium having computer readable program code embodied therewith for execution on at least one processor, the computer readable program code being configured to be executed by the at least one processor to perform: applying a hash function to a portion of sensitive information for each entity of a first entity system to produce hash values; storing transaction information pertaining to transactions performed on the first entity system within a blockchain database accessible to the plurality of entity systems having different information for at least some of the same served entities, wherein the transaction information includes the hash values for the portion of the sensitive information, and wherein the blockchain database includes transaction information from the plurality of entity systems including hash values from others of the plurality of entity systems; comparing the hash values of the first entity system to the hash values from the others of the plurality of entity systems to determine entity systems containing information pertaining to the same served entities; and exchanging the sensitive information for common served entities of the first entity system with the determined entity systems containing information for those common served entities. ### Claim 16 (depends on 15) The computer program product of claim 15, wherein the blockchain database further includes encryption parameters for encrypting data to be sent to the plurality of entity systems, and the exchanging the sensitive information comprises: encrypting the sensitive information of the common served entities utilizing the encryption parameters of each of the determined entity systems within the blockchain database, wherein the encryption parameters for a corresponding entity system are associated with a private key limiting decryption to that corresponding entity system; and transmitting the encrypted sensitive information to each of the determined entity systems for decryption via the associated private key. ### Claim 17 (depends on 16) The computer program product of claim 16, wherein the computer readable program code is further configured to be executed by the at least one processor to perform: analyzing the exchanged sensitive information to identify one or more issues triggering an action involving a served entity associated with the sensitive information. ### Claim 18 (depends on 17) The computer program product of claim 17, wherein the blockchain database further includes information from the entity systems pertaining to actions involving the served entity, and the computer readable program code is further configured to be executed by the at least one processor to perform: applying a set of rules specifying acceptable actions in the blockchain database to validate requested actions involving the served entity. ### Claim 19 (depends on 18) The computer program product of claim 18, wherein the applying of the set of rules further comprises: honoring a communication request and recording the communication request in the blockchain database when the set of rules is not violated. ### Claim 20 (depends on 15) The computer program product of claim 15, wherein: the served entities include patients, and the entity systems include healthcare systems. ### Claim 21 (depends on 20) The computer program product of claim 20, wherein the computer readable program code is further configured to be executed by the at least one processor to perform: updating the determined entity systems in response to additional data being received within a new block added to the blockchain database.