ACTA (Attestation of Creative Trajectory and Authorship): an individual-referential, artist-held provenance protocol for music composition

Every provenance layer deployed for music since 2023 serves an infrastructure: watermarks serve model vendors, content credentials serve platforms and publishers, disclosure fields serve distributors, detection stacks serve streaming economics. The artist is the object of all of them and the principal of none. Meanwhile, copyright authorities and courts increasingly examine the nature and extent of human creative control, while regulatory instruments increasingly require transparency and traceability. Yet the available infrastructure still answers with binary watermarks or self-declarations. The evidence courts actually request — documentation of the creative process — has no standard, no format, and no custody model. ACTA (Attestation of Creative Trajectory and Authorship) closes this gap by inverting the architecture. Attestation begins at the analog-to-digital conversion, accumulates through the topology of the production session, and persists in a longitudinal registry held by the artist. It is neither detection nor declaration: it is attestation of continuity, anchored to the individual baseline. We specify a canonical assertion schema as a C2PA custom-assertion extension, define the threat model, and set a three-phase implementation path from a session-file demonstrator to hardware attestation at capture. Since the first draft of this paper, the Phase-0 deliverable has been built: a complete reference implementation of the session and registry layers now runs — attestation, selective disclosure, verification, C2PA embedding, declaration projection, external time anchoring against a public RFC 3161 authority, and witness-based fork detection — carried by a test suite whose central negative results (forged proofs must fail) pass, and hardened by an adversarial review methodology (§8). This paper specifies a mechanism; real-world validation requires deployment with consenting artists under pre-registered protocols.