Alter Meridian Pty Ltd This memo specifies a wire-level annotation grammar by which a large- language-model output may carry, at emission and at the granularity of an individual assertion, a provenance label drawn from a closed enumerated vocabulary of substrate-class identifiers. The memo defines the closed vocabulary, the per-assertion attachment form, the admissibility discipline a relying party MAY apply to the labels, and two terminal output states, UNVERIFIED-INFERENCE and DECAYED-TO- UNCERTAINTY, equal-rank with assertion and denial. The memo does not specify what an inference system MUST do; it specifies the wire grammar by which a relying party may inspect what the inference system DID with respect to the substrates it consulted. The memo is Informational.