As governments push forward with digital identity initiatives and stricter compliance requirements, one challenge remains largely unsolved: how do you prove someone was physically present at a specific place and time without sacrificing privacy?
The Hashgraph Group and Truesense believe they have an answer.
The two companies announced they have jointly filed a European patent application for what they call Continuous Identity Trust Infrastructure (CITI), a new framework designed to connect real-world physical presence with decentralized digital identity credentials.
The patent application was submitted to the European Patent Office in April and covers more than 44 European jurisdictions. A separate filing process for the United States is also underway.
Loading tweet...
View Tweet
Bringing Physical Identity Onchain
At its core, CITI aims to solve a growing problem for governments, enterprises, and regulated industries.
Digital identity systems can verify who someone is online. Access control systems can verify whether someone entered a building. But linking those two events in a secure, auditable, and privacy-preserving way remains difficult.
CITI combines three emerging technologies:
Ultra-Wideband (UWB) spatial sensing
Decentralized Identifiers (DIDs)
Zero-Knowledge Proof (ZKP) cryptography
The system works by detecting a person's physical presence within a specific location using ultra-wideband technology. That presence event is then cryptographically linked to the individual's decentralized identity wallet and transformed into a verifiable credential that can later be independently validated.
Rather than exposing personal information or location data, zero-knowledge proofs allow third parties to verify the credential without revealing sensitive details.
The result is a tamper-resistant record proving that a verified individual was physically present at a specific place and time.
Why Europe Is Moving Toward Digital Identity
The timing of the patent application is notable.
SOL