Architectural Distinction Note is a metadata packet by Lee Sharks dated 28 February 2026 — DECLARED ABSENT under the Lacuna Protocol.
The note distinguished the Crimson Hexagonal Archive from an independent derivative implementation — the kind of boundary-drawing the MPAI series performs routinely, but turned inward toward a system built on the archive's own architecture rather than outward toward an unrelated namespace.
The work is lost. The record was assembled from a DataCite full-metadata capture after the 19 June 2026 termination, with no live authorial surface passing the body-head gate at restoration time. MANUS confirmed it missing on 5 August 2026 and the Lacuna Mark was declared after the recovery channels were exhausted — Blogger feed, live surfaces, corpus-wide fingerprints, and a conversation-search pass. The mark is reversible: if canonical bytes surface, a full-text version supersedes it in series.