Нормативно-правові передумови застосування zero-knowledge proof у публічних закупівлях

Abstract

The article presents a comprehensive analysis of the legal framework for public procurement in Ukraine and the European Union through the lens of balancing transparency requirements with the protection of confidential commercial information. The key principles of the Law of Ukraine “On Public Procurement” and Directive 2014/24/EU, which establish the foundations of equal treatment, non-discrimination, proportionality, and procedural openness, are examined. The practical outcomes of the Prozorro electronic procurement system are analyzed; since its launch, the system has saved over USD 8.7 billion in public funds and increased the number of bidding participants from 14,000 to 140,000. The main corruption risks at various stages of the procurement cycle are systematized – from planning and needs formulation to tender evaluation and contract execution. Based on an analysis of international studies using the Analytic Hierarchy Process (AHP) and principal-agent theory, it is established that tender evaluation is the most corruption-prone stage, with information asymmetry being the key factor. It is shown that under martial law conditions, simplified procurement mechanisms necessary for operational efficiency simultaneously expand the space for abuse. The feasibility of applying zero-knowledge proof (ZKP) protocols as a cryptographic instrument that enables combining public verification of participants’ compliance with qualification requirements while preserving the confidentiality of their commercial data is substantiated. The main classes of ZKP – interactive protocols, zk-SNARKs, zk-STARKs, and Bulletproofs – their properties, trade-offs, and practical applications in financial compliance, identity verification, and anonymous whistleblowing systems are examined in detail. Specific scenarios for integrating ZKP into public procurement procedures are considered: proof of financial capacity without disclosing reporting details, confirmation of the absence of conflicts of interest based on encrypted registry data, verification of the correctness of electronic auction results, and authentication of the supply chain. Key implementation barriers are identified: regulatory recognition of cryptographic proofs as equivalents to traditional documents, technical complexity and institutional capacity, performance and scalability concerns, legal liability for protocol errors, and compliance with GDPR requirements. A phased model for integrating ZKP into the Prozorro infrastructure is proposed, and recommendations for necessary legislative and institutional changes are formulated, including updating the Public Procurement Reform Strategy for 2024–2026, establishing independent cryptographic audit mechanisms, and developing methodological guidelines for contracting authorities.