Proof, the identity and transaction-security company formerly known as Notarize, has launched its Verifiable Digital Credential, a portable digital identity that allows consumers to complete identity proofing once and reuse that verified identity across financial institutions and other organizations that accept Proof credentials. The VDC became generally available through Proof’s platform and API on September 15. Proof has an existing network of businesses where reusable identity could potentially gain utility.  According to Proof, each credential is anchored to an individual X.509 certificate issued by its WebTrust-audited certificate authority following Kantara-certified IAL2 identity proofing. The credential is held by the consumer rather than belonging to an individual relying institution, allowing it to be presented again wherever Proof credentials are accepted.