ProofMode, developed by Guardian Project in partnership with WITNESS, is an open-source mobile camera app, toolkit and protocol, that automatically adds verifiable digital proof, including cryptographic digital signatures, third-party notarization, hardware authentication and additional supporting metadata, to photos and video at the point of capture. Proofmode can instantly share a “fingerprint” of this proof with decentralized services, such as Filecoin and IPFS, to notarize their existence on cryptographic ledgers and public storage networks. This process creates a transparent chain-of-custody from point of capture to the recipient and viewer, establishing trust in the photos and videos that are being viewed. ProofMode has enabled visual documentation efforts ranging from Emmy-nominated journalism investigations to documenting the aftermath of natural disasters. It is also compatible with the emerging Coalition for Content Provenance and Authentication (C2PA) standard backed by Adobe, Microsoft, the BBC and many others.