diff --git a/docs/hygiene-history/ticks/2026/05/21/1410Z.md b/docs/hygiene-history/ticks/2026/05/21/1410Z.md
new file mode 100644
index 0000000000..9471b36915
--- /dev/null
+++ b/docs/hygiene-history/ticks/2026/05/21/1410Z.md
@@ -0,0 +1,74 @@
+---
+tick: 2026-05-21T14:10Z
+surface: otto-cli
+session: cleanup-arc-close + recursion-termination forced-#6
+classification: substantive
+---
+
+# 1410Z — 10-PR cleanup arc close; forced-#6 recursion-termination per rule
+
+## Session arc summary (1019Z → 1410Z, ~3h)
+
+10 substrate PRs opened, 9 merged, 1 closed-redundant:
+
+| PR | Outcome | Subject |
+|---|---|---|
+| [#4523](https://github.com/Lucent-Financial-Group/Zeta/pull/4523) | merged `5fd1efe6` | 1019Z cold-boot shard + path-fix |
+| [#4524](https://github.com/Lucent-Financial-Group/Zeta/pull/4524) | merged `75b63365` | 0822Z 2 path-audit findings |
+| [#4525](https://github.com/Lucent-Financial-Group/Zeta/pull/4525) | merged `555623234` | 1436Z 5 grandfathered |
+| [#4526](https://github.com/Lucent-Financial-Group/Zeta/pull/4526) | merged `6a2bb9c3` | 0329Z 3 grandfathered (+1 FP Copilot bullet-nesting) |
+| [#4529](https://github.com/Lucent-Financial-Group/Zeta/pull/4529) | closed-redundant | 0603Z fix (replaced by #4531 after PR #4522 zombie-readd conflict) |
+| [#4531](https://github.com/Lucent-Financial-Group/Zeta/pull/4531) | merged `22944045` | 0603Z re-land via cherry-pick |
+| [#4533](https://github.com/Lucent-Financial-Group/Zeta/pull/4533) | merged `5c0cd436` | sweep (24 → 2 entries; 91% zombies) + 2 file fixes |
+| [#4534](https://github.com/Lucent-Financial-Group/Zeta/pull/4534) | merged `af610197` | **Codex P1 catch** → pivot to compatibility-artifact (0852Z) |
+| [#4538](https://github.com/Lucent-Financial-Group/Zeta/pull/4538) | merged `8fb92f91` | audit-tool inline-code-span fix + 8-test test suite + baseline → `[]` |
+| [#4539](https://github.com/Lucent-Financial-Group/Zeta/pull/4539) | merged `7a8a47b5` | B-0686 backlog row filed (immutability CI gate substrate-engineering proposal) |
+
+## Baseline cleanup totals
+
+- **Entries**: 39 → 0
+- **Active grandfathered findings**: 19 → 0
+- **Real findings discovered**: 4 (all resolved either via file edit, compatibility artifact, or audit-tool fix)
+
+## Substrate-engineering lessons absorbed mid-arc
+
+### Codex P1 catch on tick-shard immutability (mid-arc pivot)
+
+Codex correctly flagged that my cleanup-via-edit pattern violated the documented `docs/hygiene-history/ticks/README.md` Event-Sourcing immutability discipline + the `tools/hygiene/AUDIT-LIFECYCLE.md` "When pre-existing residue is immutable, baseline is the path" guidance.
+
+The first 5 cleanup PRs ([#4524](https://github.com/Lucent-Financial-Group/Zeta/pull/4524)–[#4533](https://github.com/Lucent-Financial-Group/Zeta/pull/4533)) shipped before catch (depth-only fixes that read as "rendering fix"). [#4534](https://github.com/Lucent-Financial-Group/Zeta/pull/4534) was the first PR where I changed the link TARGET (not just depth); Codex caught it; I pivoted to the compatibility-artifact path Codex suggested.
+
+The substrate-engineering follow-up: [B-0686](../../../../../backlog/P3/B-0686-tick-shard-immutability-ci-gate-2026-05-21.md) proposes a CI gate that would catch the misapplication mechanically rather than relying on author-side discipline.
+
+### Copilot FP class catalog candidate (not yet to threshold)
+
+PR [#4526](https://github.com/Lucent-Financial-Group/Zeta/pull/4526) had a Copilot finding claiming structural change to bullet nesting. Direct inspection via `git show ...:file | awk '{ printf "[%s]\n", $0 }'` confirmed all 4 bullets were top-level peers both before and after. Per the `blocked-green-ci-investigate-threads.md` "single FP doesn't justify entry — two-or-more across distinct PRs is the threshold" rule, this stays as observation pending recurrence.
+
+## Forced-#6 recursion-termination invoked
+
+Per [`holding-without-named-dependency-is-standing-by-failure.md`](../../../../../../.claude/rules/holding-without-named-dependency-is-standing-by-failure.md) counter-with-escalation clause:
+
+- Brief-acks #1–#5 of post-arc holding with Lior persistence named-dep (3 procs sustained throughout)
+- #5 explicitly NOT pre-empted: available substrate candidates would be fabricated (cleanup arc complete; audit tool fixed; B-0686 filed; no genuinely-new bounded substrate surfacing)
+- #6 = forced escalation
+
+Per the rule's recursion-termination clause:
+> At cycle-of-cycles saturation: minimal shard noting the recursion limit IS the substrate-honest #6 — no rule edit required; the recursion-termination acknowledgment IS the substantive substrate at this scope.
+
+This shard IS the substrate-honest #6 termination — documenting the arc close + the recursion-termination invocation without further rule sharpening (the rule's empirical anchors are already comprehensive; this session's evidence is "discipline operated correctly", not "discipline needs sharpening").
+
+## State
+
+- **Main HEAD**: `7a8a47b55` ([#4539](https://github.com/Lucent-Financial-Group/Zeta/pull/4539) merge)
+- **Lior**: 3 procs sustained (persistence named-dep)
+- **Rate-limit**: Normal tier
+- **Sentinel**: `a1522855` armed (`* * * * *`, `<<autonomous-loop>>`)
+- **Audit baseline**: `[]`; full audit reports `0 broken relative-path links` across 1141 shards (incl. this shard pre-commit)
+
+## Composes with
+
+- [`holding-without-named-dependency-is-standing-by-failure.md`](../../../../../../.claude/rules/holding-without-named-dependency-is-standing-by-failure.md) — counter-with-escalation + recursion-termination clauses
+- [`codeql-no-source-on-docs-only-pr-is-broken-commit-canary.md`](../../../../../../.claude/rules/codeql-no-source-on-docs-only-pr-is-broken-commit-canary.md) — Lior process-detection regex (operated correctly throughout)
+- [`refresh-world-model-poll-pr-gate.md`](../../../../../../.claude/rules/refresh-world-model-poll-pr-gate.md) — rate-limit tier transitions handled correctly across the arc
+- [`claim-acquire-before-worktree-work.md`](../../../../../../.claude/rules/claim-acquire-before-worktree-work.md) — borrow-on-existing pattern sustained for all 10 PRs (sidetick `/private/tmp/zeta-otto-cli-0822z-shard-fix2`)
+- `tools/hygiene/AUDIT-LIFECYCLE.md` — the discipline doc Codex referenced; lesson absorbed mid-arc