Device for the secure digital management of property rights and lease agreements

Abstract

A secure digital management tool for managing real estate ownership and leases, consisting of: a tamper-proof enclosure containing a secure processing module; a biometric authentication module comprising a fingerprint sensor and an iris scanner, which are operationally coupled with a secure biometric engine to verify a user's physical identity; a document integrity module configured to generate a cryptographic hash of a digital document representing a certificate of ownership or a lease agreement; a smart contract engine configured to compile and execute the logic for legal transactions related to ownership in a Turing-complete virtual machine environment, the logic defining obligations, rights, payment schedules or renewal triggers encoded in the lease or ownership contract; a blockchain interface processing unit operationally connected to the document integrity module and the smart contract engine, wherein the blockchain interface processing unit is configured to anchor cryptographic hashes of the documents and the execution status of smart contracts in a decentralized ledger network; a secure element embedded in the secure processing module and configured to store cryptographic private keys and perform isolated signature and encryption operations without exposing confidential key material to general storage space; a communication subsystem that includes at least one of the following elements: a GSM / 4G module, a Wi-Fi 6 module and a GPS receiver, configured for secure network connectivity and geolocation binding of transactions; a touchscreen interface configured for displaying transaction forms, digital agreements, and interactive contract signing interfaces, the interface also including pen input for capturing digital handwritten signatures; and a secure audit trail subsystem configured to maintain a chronologically ordered, append-only log of all biometric access events, document hash generations, blockchain anchoring events, and smart contract lifecycle transitions, with the audit trail regularly hashed and anchored for forensic integrity in a decentralized blockchain network.

Description

Field of invention

[0001] The present invention relates to secure digital data management and, in particular, a device and system for the secure digital handling, verification, and real-time synchronization of ownership and lease agreements. It comprises secure hardware modules, blockchain integration, biometric access, and smart contract orchestration to prevent document fraud, improve verifiability, and facilitate the legal enforceability of real estate transactions. Background of the invention

[0002] Traditional property management systems rely heavily on paper-based documents, manual processes, and third-party review. This leads to inefficiency, human error, and a high risk of document fraud. The decentralized nature of property transactions—often involving owners, tenants, notaries, local authorities, and legal intermediaries—makes ensuring document integrity and traceability difficult. Existing digital document management platforms are fragmented, insecure, and typically lack tamper-proof cryptographic anchoring or real-time validation of ownership status. Furthermore, digital leases are often disconnected from regulatory compliance frameworks, fail to enforce automated obligations, and lack verifiable biometric linking of the parties involved.Therefore, there is an urgent need for a unified, secure and machine-readable system that enables transparent, verifiable and tamper-proof ownership authentication, lease automation and digital notarization of real estate transactions.

[0003] Managing title and lease agreements has traditionally been a complex, paper-intensive process prone to delays, fraud, and administrative inefficiencies. In both developed and developing countries, property registration often requires multiple in-person visits to government offices, notarization through manual review, and handling fragile paper documents vulnerable to loss, tampering, and unauthorized duplication. Existing title and lease management systems lack a unified digital framework capable of ensuring the authenticity, traceability, and long-term verifiability of documents. This is particularly concerning in jurisdictions where disputes over land ownership and lease rights due to unrecorded or fraudulently duplicated title deeds are common.

[0004] While modern digitization efforts offer some improvements over manual systems, they still fall short of expectations in terms of security, trust, and automation. Many governments and real estate management platforms have implemented digital record-keeping systems or electronic document repositories. These include centralized land registry databases, document management systems (DMS), and web-based contract management portals. These systems allow users to upload leases, deeds, and other related documents for storage, tracking, and basic auditing purposes. However, the centralized nature of such platforms creates a central vulnerability and poses the risk of insider manipulation, data loss due to system failures, or unauthorized administrative override.The inherent trust model of these centralized systems is based more on the integrity of the host institution than on verifiable technological guarantees.

[0005] In recent years, several jurisdictions and private entities have experimented with blockchain-based systems for recording real estate transactions. These systems store cryptographic hashes of property documents or leases on public or authorized blockchain networks. The goal is to ensure immutability and traceability through decentralized ledgers. While this approach promises to prevent document tampering and permanently record transactions, current implementations are fragmented and lack integration with real-world identity verification and biometric authentication systems. Blockchain-based land registries also frequently suffer from the oracle problem, where the reliability of the data fed into the system is not guaranteed.If a false or fraudulent document is stored on the blockchain, the immutability of the blockchain only ensures that the error persists. Therefore, any blockchain-based solution must be closely linked to a trusted identity validation and presence authentication mechanism to guarantee legally binding validity.

[0006] Some property management solutions offer lease automation through Software-as-a-Service (SaaS) platforms. These platforms allow landlords and tenants to digitally sign documents using cloud-based digital signature services, track rent payments, and set up lease renewal reminders. However, these platforms typically rely on third-party email- or password-based authentication systems, which are vulnerable to phishing, account hijacking, and identity theft. Furthermore, the digital signature mechanisms of many of these systems are not legally binding in all jurisdictions, especially if the signatures are not backed up by biometric verification or government-verified identity integration. Therefore, the enforceability of these digital leases in property disputes or for official registration is questionable.

[0007] Furthermore, there are enterprise-wide document verification platforms that use Public Key Infrastructure (PKI) for secure digital signatures and timestamps. These are commonly used in banking and legal sectors, but are often expensive, complex to implement, and not tailored to the nuances of real estate workflows. PKI-based systems also assume that the private key holder always retains control over their credentials, which is not always the case with shared ownership models or compromised devices. Many users lack the technical expertise to manage digital certificates or understand the implications of key revocation and reissuance. Therefore, despite their theoretically robust functionality, such systems are not commonly used in property and rental management.

[0008] Another solution focuses on the tokenization of real estate and fractional ownership using blockchain tokens. These systems convert real estate values ​​into digital tokens, enabling micro-investments and simplified transfers of ownership shares. While innovative, such systems are subject to highly regulated conditions and often fail to comply with local real estate laws and zoning codes. Furthermore, they do not address the core issues of tenancy enforcement, identity verification, and document traceability present in traditional rental scenarios. These tokenization approaches also often lack physical devices or interfaces that can be integrated into existing workflows, making them inaccessible to notaries, tenants, or landlords unfamiliar with blockchain technology.

[0009] A major drawback of existing solutions is the lack of interoperability between systems. Digitally generated leases from a SaaS provider may not be accepted by a local authority using an outdated database format. Similarly, a blockchain-based document may not be admissible in court because it requires certified physical copies. The absence of standardized protocols for digital property documents makes it difficult to align the interests of various stakeholders—including landlords, tenants, local registries, judicial authorities, and financial institutions. In such an environment, errors in documentation, missing certifications, and incomplete registrations frequently lead to legal disputes, tenant harassment, or the loss of property rights.

[0010] From a user-friendliness perspective, existing digital platforms often lack robust user interfaces and offline operating modes. Therefore, they are unsuitable for use in rural areas, small towns, or regions with limited digital infrastructure. These platforms also frequently require internet access and assume technically savvy users. This overlooks the needs of elderly landlords, lawyers, or tenants unfamiliar with complex authentication processes. Many digital solutions also fail to support biometric or multi-factor authentication, leading to an increased risk of fraud in high-value real estate transactions.

[0011] Furthermore, conventional systems lack a unified audit trail that combines biometric presence, real-time document versioning, cryptographic anchoring, and legally recognized timestamps. This lack of holistic auditability prevents regulators from conducting efficient investigations in property disputes or tenancy violations. Manual logs or fragmented metadata from disparate platforms cannot be effectively reconciled, leading to time-consuming and costly legal proceedings.

[0012] Furthermore, most current solutions lack tamper-proof physical interfaces that could be installed in government offices, notaries' offices, or real estate centers for secure on-site document processing. The lack of dedicated hardware makes it difficult to protect signature and verification processes from screen spoofing, unauthorized keystroke logging, and other software-level attacks. Without a secure enclave for biometric authentication and cryptographic signatures, any internet-connected device becomes a potential target for malware or remote exploitation, jeopardizing the integrity of rental or real estate documents.

[0013] The current landscape of digital real estate and lease management is therefore characterized by several problems: centralization risks, insufficient identity binding, lack of legal enforceability, lack of blockchain oracle integration, device-level vulnerabilities, and a lack of regulatory interoperability. These limitations underscore the urgent need for a comprehensive, hardware-integrated, blockchain-based, and biometric system that ensures secure, tamper-proof, and legally compliant processing of real estate ownership and lease agreements. A device-based solution that combines secure hardware, smart contract automation, identity verification, and cryptographic transparency in a single, user-friendly unit can effectively close this gap and create a trusted framework for modern real estate transaction management. Summary of the invention

[0014] The invention provides a secure digital management system embedded in a physical device structure, the so-called PropertySec Node. This device consists of a tamper-proof enclosure containing a processor, secure key storage (TPM / SE), a smart contract engine, a biometric authentication module, an integrated camera and scanner for ID verification, and a blockchain interface chip. The device connects securely to a decentralized network of land registries and municipal land registry offices via end-to-end encrypted APIs. The PropertySec Node enables parties to initiate, execute, and validate property transfers and leases via digitally signed smart contracts anchored on an authorized or public blockchain. It utilizes a local secure enclave to perform private key operations without exposing raw user interface data.Biometric input such as fingerprints or iris scans ensures the linking of legal documents to the physical identity of all parties involved. Every lease or property deed is cryptographically hashed and stored on the blockchain. The corresponding metadata outside the blockchain is stored in encrypted device memory and optionally replicated to regulatory nodes. The device features a tamper-proof 7-inch touchscreen with eSign input capability, dual-band Wi-Fi and GSM modules, GPS-based location tracking, and a battery-backed real-time clock for timestamp integrity. Smart contracts embedded in the system can trigger automated actions such as rent payment reminders, eviction notices, renewal offers, or the marking of liens based on predefined business rules.The flash memory maintains a tamper-proof log that records every access attempt, transaction modification, and hash verification event, thus providing verifiable forensic evidence. The PropertySec Node can be integrated into smart city infrastructure, such as notaries' offices, land registries, real estate agencies, or as a secure kiosk.

[0015] The main objective of the present invention is to provide a secure, tamper-proof digital device for the end-to-end management of real estate ownership and lease agreements, enabling legally verifiable documentation, authentication, and execution of real estate transactions both online and offline. A key objective is to ensure that all critical operations—such as the creation, signing, and storage of title deeds or lease agreements—are anchored in cryptographic protocols and secured in a hardware-based, trusted execution environment. This prevents unauthorized modifications, data breaches, and identity theft.The invention also aims to replace fragmented, paper-based workflows with an integrated, biometrically linked smart contract system that can automate legal obligations such as rent payments, renewal notifications and lease terminations in accordance with applicable real estate laws.

[0016] Another objective is to provide a dedicated physical device structure—designed for installation in land registries, notary kiosks, or legal advice centers—that enables secure, personal digital document review through biometric authentication and ID scanning. The invention is intended to offer compatibility with existing municipal land registry and legal databases via a standards-compliant API framework, thus ensuring interoperability and regulatory compliance. A further objective is the generation of immutable audit trails using blockchain hashing techniques, providing independently verifiable, timestamped records of each transaction or document revision that can serve as forensic evidence in legal disputes.

[0017] The invention is also intended to bridge the digital divide, offering a user-friendly touchscreen interface with offline document creation, battery-backed operation, and intuitive workflows accessible even to less technically savvy users. Furthermore, it aims for a tamper-proof physical design with embedded security features and a Trusted Platform Module (TPM) that protects sensitive keys and performs cryptographic operations in isolation. Another objective of the invention is the real-time execution of electronic signatures by multiple parties using secure digital workflows with biometric binding to ensure the legal and physical accountability of each signatory. BRIEF DESCRIPTION OF THE FIGURE

[0018] These and other features, aspects, and advantages of the present invention will be better understood if the following detailed description is read with reference to the accompanying drawing, in which the same symbols consistently represent the same parts. The following applies: Fig. Figure 1 shows a block diagram of a device for the secure digital management of real estate ownership and leases.

[0019] Experts will also recognize that the elements in the drawing are shown for the sake of simplicity and are not necessarily to scale. For example, the flowcharts illustrate the process by highlighting the main steps to enhance understanding of the aspects of this disclosure. Furthermore, with regard to the design of the device, one or more components of the device may be represented in the drawing by conventional symbols, and the drawing may show only the specific details relevant to understanding the embodiments of this disclosure, so as not to clutter the drawing with details that are readily apparent to those skilled in the art after reading this description. Detailed description of the invention

[0020] For a better understanding of the inventive principles, reference is made below to the embodiment shown in the drawing, which is described in specific terminology. However, this does not limit the scope of the invention. Changes and further modifications of the illustrated system, as well as further applications of the inventive principles, are possible, as would normally occur to a person skilled in the art in the field of invention.

[0021] It is clear to the person skilled in the art that the preceding general description and the following detailed description are exemplary and explanatory of the invention and are not intended as a limitation of it.

[0022] References in this specification to “an aspect”, “another aspect”, or similar expressions mean that a particular feature, structure, or property described in connection with the embodiment is included in at least one embodiment of the present disclosure. Therefore, occurrences of the expressions “in one embodiment”, “in another embodiment”, and similar expressions in this specification may all refer to the same embodiment, but need not.

[0023] The terms "includes," "include," or other variations thereof are intended to cover non-exclusive inclusion, such that a process or method that includes a list of steps may not only contain those steps but may also include other steps not expressly listed or inherent in such process or method. Likewise, the statement "includes..." in the case of one or more devices, subsystems, elements, structures, or components does not, without further limitations, preclude the existence of other devices, subsystems, elements, structures, components, or additional devices, subsystems, elements, structures, or components.

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as understood by a person skilled in the art in the field of the invention. The system, methods, and examples provided here serve only for illustration and are not to be construed as a limitation.

[0025] Embodiments of the present disclosure are described in detail below with reference to the attached drawing.

[0026] Fig.Figure 1 shows a block diagram of a device for the secure digital management of ownership and lease agreements. The System 100 comprises: a tamper-proof enclosure with a secure processing module (102); a biometric authentication module (104) with a fingerprint sensor and an iris scanner, operationally linked to a secure biometric engine for verifying a user's physical identity; a document integrity module (106) configured to generate a cryptographic hash of a digital document representing a proof of ownership or lease agreement using SHA-3 technology; and a smart contract engine (108) configured to compile and execute the logic for legal ownership transactions in a Turing-complete virtual machine environment. This logic defines obligations, rights, payment schedules, or renewal triggers encoded in the lease or ownership agreement.a blockchain interface processing unit (110) operationally connected to the document integrity module and the smart contract engine, wherein the blockchain interface processing unit is configured to anchor cryptographic hashes of the documents and the execution state of smart contracts in a decentralized ledger network; a Trusted Platform Module (TPM) and a Secure Element (SE) (112), both embedded in the secure processing module and configured to store cryptographic private keys and to perform isolated signature and encryption operations without exposing confidential key material to common storage space; a communications subsystem (114) comprising at least one of the following: a GSM / 4G module, a Wi-Fi 6 module, and a GPS receiver, configured for secure network connectivity and geolocation of transactions;a touchscreen interface (116) configured to display transaction forms, digital agreements, and interactive interfaces for contract signing, the interface also including pen input for capturing digital handwritten signatures; and a secure audit trail subsystem (118) configured to maintain a chronologically ordered, append-only log of all biometric access events, document hash generations, blockchain anchoring events, and smart contract lifecycle transitions, the audit trail being hashed regularly and anchored to a decentralized blockchain network for forensic integrity.

[0027] In one embodiment, the biometric authentication module (104) includes a template protection mechanism that uses cancelable biometric data or homomorphic encryption to prevent the reconstruction of raw biometric data and thus enable a revocable biometric identity without compromising the reliability of authentication.

[0028] In one embodiment, the document integrity module (106) is also configured to perform dual hashing. A first hash is generated using a user-defined content area of ​​the digital document to ensure signature consistency, and a second hash of the entire document is calculated for anchoring in the blockchain ledger. The two hashes are cryptographically linked via a Merkle tree structure stored locally on the device.

[0029] In one embodiment, it includes a sandbox execution environment on which a WebAssembly-based virtual machine runs, in which lease agreements are compiled into bytecode and contain coded conditional logic for verifying time-bound rent payments, an automatic renewal trigger based on the tenant's compliance rating, and the execution of penalties such as access restrictions or the generation of legal notices upon detection of predefined breaches of contract.

[0030] In one embodiment, it is also configured to operate in dual-chain mode, with the document's cryptographic hash simultaneously anchored in a regulatory-accessible, approval-required Hyperledger Fabric chain and in a public, Ethereum-compatible blockchain, thereby ensuring both privacy-controlled auditability and public transparency.

[0031] In one embodiment, the Trusted Platform Module (TPM) and the Secure Element (SE) (112) are also configured to implement a split-key signing protocol in which a private key fragment stored in the TPM is combined with a session-specific key fragment generated by the SE via an elliptic curve Diffie-Hellman exchange. This enables the derivation of volatile keys for each transaction without storing complete private keys in an accessible storage domain.

[0032] In one embodiment, it also includes a policy-enforced VPN tunnel managed by an embedded network access controller, the controller being configured to prevent data transmission unless the GPS module confirms that the device is operating within a geofencing region authorized for the execution of real estate transactions, such as a certified notary's office or land registry.

[0033] In one embodiment, the touchscreen interface (116) is equipped with capacitive and pressure-sensitive layers capable of capturing dynamic biometric signature features such as stroke pressure, speed, angle, and pen orientation. The captured data are locally signed and linked to the hash of the signed document to confirm the signer's intent using behavioral biometrics.

[0034] The secure audit trail subsystem (118) includes a hardware-based real-time clock and a flash memory partition protected by physically non-clonable feature keys (PUFs), wherein each audit event is time-stamped with high precision, encrypted, and regularly entered into a tamper-proof journal using an append-only ring buffer structure, thus preventing retrospective modification of historical records.

[0035] In one embodiment, the device is also configured to operate in an offline transaction preparation mode, in which signed and hashed ownership documents, along with their verification metadata, are queued locally and batch-synchronized with blockchain and regulatory nodes after network connectivity is restored, with automatic nonce conflict resolution and replay protection mechanisms in place to prevent transaction duplication or rollback attacks.

[0036] The secure digital management tool for real estate ownership and leases operates through a series of interdependent modules that ensure the integrity, authenticity, and enforceability of every transaction. Central to the system's functionality is the coordination between the biometric authentication module, the document integrity module, the smart contract engine, and the blockchain anchor interface. These subsystems work together under the control of a secure processing environment, reinforced by embedded Trusted Platform Modules (TPMs) and Secure Elements (SEs).

[0037] When a user initiates a transaction, such as creating or signing a lease or deed, the process begins with biometric authentication. The device uses capacitive or optical sensors to capture a high-resolution fingerprint or iris scan. This is then compared to pre-registered templates stored in the secure biometrics engine. The matching process is not based on the static storage of raw biometric data. Instead, the system uses reversible biometric transformations or homomorphic encryption to convert the input into a revocable template that enables authentication without revealing raw identity characteristics. This protects against identity theft, even in the event of a physical or software attack.

[0038] After successful authentication, the user can complete, modify, or approve a property document via the touchscreen interface. The touchscreen integrates a pressure-sensitive signature capture system that records not only the visual form of the signature but also behavioral dynamics such as stroke sequence, speed, pressure, and pen tilt angle. These dynamic characteristics are converted into a behavioral biometric hash, which is stored with the document and linked to the signer's identity. The document itself, whether a lease or a deed, is passed to the document integrity module, which initiates a dual-hashing process. First, a user-defined critical area of ​​the document—such as names, dates, and monetary terms—is selected and hashed independently to detect tampering with key areas. Then, an SHA-3 hash is generated for the entire document.These two hashes are used to form a Merkle tree, with the root hash stored locally and the leaf hashes anchored in both authorized and public blockchain networks via the blockchain interface processing unit.

[0039] The blockchain anchoring process operates in dual-chain mode. The hash is sent to an authorized Hyperledger Fabric chain, accessible to municipal and land registry offices. Simultaneously, an anchoring transaction is submitted to a public blockchain such as Ethereum to ensure global transparency. The device utilizes volatile key derivation via a secure split-key signing mechanism. Specifically, the TPM stores a long-term key fragment, while the SE generates a session-specific key fragment. These are combined using an elliptic curve Diffie-Hellman exchange to create a transaction-specific private key, which is used to sign the blockchain transaction without ever exposing the full private key in memory.

[0040] Simultaneously, the smart contract engine is invoked. This engine runs in a sandboxed WebAssembly virtual machine environment and compiles the legal logic embedded in the lease or ownership agreement into executable bytecode. The contract logic includes terms such as payment deadlines, renewal clauses, automatic escalation triggers, and breach handling mechanisms. For example, a lease agreement might stipulate that if payment is not received by the 5th of each month, a penalty is triggered, and the device automatically sends a smart notice via blockchain to the tenant and the local authority. These contract terms are managed in real time, with the contract status stored both on the blockchain and in the device's encrypted local storage.

[0041] To ensure operational integrity and legal auditability, every action—biometric login, document signing, hash generation, blockchain anchoring, contract execution—is recorded by the secure audit trail subsystem. This subsystem includes a battery-powered real-time clock protected by encryption keys derived from physically non-cloning functions (PUFs), ensuring tamper-proof logging. Each log entry contains a timestamp, device geolocation, document ID, user ID, and a hash of the associated transaction or contract status. The logs are organized in an append-only ring buffer architecture and are periodically transferred to a blockchain via a low-frequency anchoring protocol to minimize transaction costs while maintaining forensic integrity.

[0042] For scenarios with poor network connectivity or offline environments, the device supports a transaction queue protocol. In offline mode, all signed and hashed documents, along with their audit logs, are securely stored in encrypted memory. Once network access is restored, the system performs a batch synchronization. To prevent transaction repetition or duplication during this catch-up phase, the blockchain interface processing unit applies nonce conflict resolution and timestamp sorting techniques based on pending status queries to the target blockchain. Each queued transaction includes a timestamp hash and a nonce hash, signed using the temporary key strategy. The smart contract engine performs pre-commit checks to ensure the integrity of the synchronization.

[0043] The entire system is designed to operate within a geofenced security policy. The communication subsystem integrates GPS hardware and verifies the device's location before allowing transactions. The embedded network access controller checks whether the device is operating within approved zones—such as certified real estate offices or land registries—before establishing VPN tunnels to external blockchain nodes or municipal registries. If the device moves outside an approved zone, it enters a restricted mode and disables sensitive transaction functions until a proper reverification is completed.

[0044] The technical structure thus combines strong cryptographic anchoring, enforceability of smart contracts, biometric identity binding, and physical device security within a unified framework. Each subsystem is independently verifiable yet tightly integrated, enabling the device to serve as a legally valid instrument for executing and recording property transfers and lease obligations. By ensuring that every document is verifiable both humanly and machine-wise, time-bound, and tamper-proof, the invention addresses long-standing challenges in real estate documentation, regulatory compliance, and fraud prevention.

[0045] The hardware architecture comprises an ARM-based security processor (120) in a robust, tamper-evident package (100) made of reinforced polycarbonate with electromagnetic shielding to prevent side-channel attacks. A Secure Element Chip (121) and a Trusted Platform Module (122) are integrated, enabling secure key storage and isolated cryptographic operations. These modules are connected to the main controller via SPI / I2C buses and ensure that all signing and encryption operations are performed within a hardware root-of-trust zone.

[0046] A biometric module (130) comprises a capacitive fingerprint sensor and an optional iris scanner, connected to a secure biometric engine (131). This module ensures that user authentication is tied to presence and consent. An identity verification module (140) consists of a high-resolution document scanner and a facial recognition camera that validates identity cards, passports, and other notarized documents. Thanks to real-time OCR analysis and photo comparison evaluation, the system can reject forged or altered identity information.

[0047] The display interface (150) is a 7-inch touchscreen LCD that enables digital signatures with a stylus and visualizes rental / ownership documents. The communication subsystem (160) includes a GSM / 4G module with VPN-based encrypted communication, Wi-Fi 6 compatibility, and an optional Ethernet interface. This enables secure connectivity to municipal land registries, regulatory APIs, and external blockchain nodes. A GPS module (161) provides geolocation metadata embedded in transaction hashes, ensuring the spatial authenticity of real estate transactions.

[0048] The document workflow subsystem (230) enables the forwarding of electronic signatures by multiple parties, the scripting of rental terms (e.g., start / end dates, rent amount, late payment penalties), and event triggers. The audit trail engine (240) maintains a chronologically ordered log of all actions performed on the device, which is secured via Merkle tree structures and anchored daily in the blockchain ledger to ensure compliance with audit requirements.

[0049] The user interface module (250) includes both a touchscreen and a remote web interface (via HTTPS / VPN tunnel), enabling the secure review, initiation, and execution of real estate-related transactions. Furthermore, regulatory authorities can remotely verify compliance with lease agreements and flag fraudulent entries via administrative dashboards.

[0050] An energy management system (260) includes an uninterruptible power supply with lithium-ion battery backup, enabling autonomous operation for 8 hours, and a tamper detection circuit that irrevocably locks cryptographic keys in the event of attempts to break into the enclosure.

[0051] During operation, when initiating a real estate lease or transferring ownership, the parties are authenticated using biometric verification. The proposed lease or ownership transfer agreement is generated on the touchscreen or via external systems connected to the device. Each party signs digitally using an eSign mechanism that links their biometric identity to the document's hash. The signed agreement is hashed, timestamped, and published on the blockchain. A QR code containing the blockchain hash reference is attached to the document, allowing any external party to verify its authenticity by checking the on-chain digest.

[0052] Upon completion of the transaction, a copy of the signed document, transaction metadata, and audit logs are encrypted and stored locally. Optionally, they can be synchronized with regulatory backends via secure API calls. Smart contracts continue to monitor the lease terms, inform the parties of any relevant obligations, and automatically enforce the consequences.

[0053] The present invention relates to the technical fields of secure digital systems, legal technology, and decentralized data integrity mechanisms. Specifically, it is a device-based system for the secure creation, authentication, execution, and storage of title deeds and leases using advanced cryptographic techniques, biometric identity verification, blockchain anchoring, and smart contract execution. The invention integrates secure hardware modules, secure key enclaves, and tamper-proof digital audit logs and is applicable in environments requiring verifiable and enforceable digital transactions, such as land registries, notary authentication centers, and smart legal infrastructures for property management.

[0054] The drawing and the preceding description show examples of embodiments. Those skilled in the art will recognize that one or more of the described elements can be combined to form a single functional element. Alternatively, certain elements can be divided into several functional elements. Elements of one embodiment can be added to another embodiment. For example, the sequence of the processes described here can be changed and is not limited to the manner described here. Furthermore, the actions of a flowchart need not be implemented in the sequence shown; nor does it necessarily have to be performed by all actions. Actions that are not dependent on other actions can also be performed in parallel with the other actions. The scope of the embodiments is in no way limited by these specific examples.Numerous variations are possible, whether explicitly stated in the specification or not, such as differences in structure, dimensions, and material use. The range of embodiments is at least as broad as specified in the following claims.

[0055] Advantages, further benefits, and problem solutions have been described above with reference to specific embodiments. However, the advantages, benefits, problem solutions, and all components that can lead to an advantage, benefit, or solution occurring or becoming more apparent are not to be construed as critical, necessary, or essential features or components of individual or all claims. REFERENCES 100 One device for the secure digital management of property rights and rental agreements. 102 Secure Processing Module 104 A biometric authentication module 106 Module on Document Integrity 108 Smart Contract Engine 110 Blockchain interface processing unit 112 Safe element 114 Communication subsystem 116 Touchscreen surface 118 Secure Audit Trail Subsystem

Claims

[1] A secure digital management device for managing real estate ownership and leases, consisting of: a tamper-proof enclosure containing a secure processing module; a biometric authentication module comprising a fingerprint sensor and an iris scanner, which are operationally coupled with a secure biometric engine to verify a user's physical identity; a document integrity module configured to generate a cryptographic hash of a digital document representing a certificate of ownership or a lease agreement; a smart contract engine configured to compile and execute the logic for legal transactions related to ownership in a Turing-complete virtual machine environment, the logic defining obligations, rights, payment schedules or renewal triggers encoded in the lease or ownership contract; a blockchain interface processing unit operationally connected to the document integrity module and the smart contract engine, wherein the blockchain interface processing unit is configured to anchor cryptographic hashes of the documents and the execution status of smart contracts in a decentralized ledger network; a secure element embedded in the secure processing module and configured to store cryptographic private keys and perform isolated signature and encryption operations without exposing confidential key material to general storage space; a communication subsystem that includes at least one of the following elements: a GSM / 4G module, a Wi-Fi 6 module and a GPS receiver, configured for secure network connectivity and geolocation binding of transactions; a touchscreen interface configured for displaying transaction forms, digital agreements, and interactive contract signing interfaces, the interface also including pen input for capturing digital handwritten signatures; and a secure audit trail subsystem configured to maintain a chronologically ordered, append-only log of all biometric access events, document hash generations, blockchain anchoring events, and smart contract lifecycle transitions, with the audit trail regularly hashed and anchored for forensic integrity in a decentralized blockchain network. [2] Device according to claim 1, wherein the biometric authentication module comprises a template protection mechanism that uses cancelable biometric data or homomorphic encryption to prevent the reconstruction of raw biometric data and thus enable a revocable biometric identity without compromising the reliability of authentication. [3] The device according to claim 1 is further configured to perform dual hashing, wherein a first hash is generated using a user-defined content area of ​​the digital document to ensure signature consistency, and a second hash of the entire document is calculated for anchoring in the blockchain ledger, the two hashes being cryptographically linked via a Merkle tree structure stored locally on the device. [4] The device according to claim 1 is also configured for operation in dual-chain mode, wherein the cryptographic hash of the document is simultaneously anchored in a regulatory-accessible, approval-required Hyperledger Fabric chain and in a public, Ethereum-compatible blockchain, thereby ensuring both privacy-controlled verifiability and public transparency. [5] Device according to claim 1, wherein the communication subsystem comprises a policy-enforced VPN tunnel managed by an embedded network access controller, the controller being configured to prevent data transmission unless the GPS module confirms that the device is operating within a geofencing region authorized for the execution of real estate transactions, such as a certified notary's office or a land registry. [6] Device according to claim 1, wherein the touchscreen interface is equipped with capacitive and pressure-sensitive layers capable of capturing dynamic biometric signature features such as stroke pressure, speed, angle and pen orientation, wherein the captured data are locally signed and linked to the hash of the signed document to confirm the signer's intent behaviorally biometrically. [7] Device according to claim 1, wherein the secure audit trail subsystem comprises a hardware-based real-time clock and a flash memory partition protected by physically non-clonable function keys (PUFs), wherein each audit event is time-stamped with high precision, encrypted and regularly recorded in a tamper-proof journal using an append-only ring buffer structure, thereby preventing retrospective modification of historical records.

Images