EA-SEI-ADVERSARY-01 Addendum: First Confirmation Marker is a forensic record by Johannes Sigil, deposited 13 June 2026 — the day after the paper it extends.
Adversarial by Origin stated five falsification conditions in its Section IX and, conversely, listed confirmation markers — instances whose occurrence would confirm the thesis. This addendum records the first such instance arriving, one day later.
The structure is the archive's falsifiability discipline working as designed. A paper that names in advance both what would refute it and what would confirm it converts a subsequent event from anecdote into evidence, because the criterion was fixed before the observation. Depositing the confirmation as a dated addendum rather than editing it into the parent keeps the sequence auditable: the prediction and its satisfaction remain separately timestamped.