diff --git a/.changeset/comment-gate-own-depth-contract.md b/.changeset/comment-gate-own-depth-contract.md
new file mode 100644
index 0000000000..73659c0abc
--- /dev/null
+++ b/.changeset/comment-gate-own-depth-contract.md
@@ -0,0 +1,30 @@
+---
+"@objectstack/spec": patch
+"@objectstack/plugin-audit": patch
+---
+
+docs(spec,plugin-audit): record that the parent-record write gates match ownership at `own` BY DESIGN (#7144)
+
+Documentation only — no gate changes what it returns for any input.
+
+`ISharingService`'s write gates widen ownership "by write DEPTH", but that depth
+is an INPUT the caller supplies: the CRUD middleware resolves it for the object
+of the operation in flight and stamps it on the operation context. The
+`sys_comment` gates (`@objectstack/plugin-audit`) and the `sys_attachment` kit
+(`@objectstack/service-storage`) ask this service about the PARENT record's
+object, so the stamped depth belongs to a different object and is dropped — and
+the owner-match runs at its narrowest, `own`. A caller whose write depth on the
+parent is `unit` / `unit_and_below` / `org` can therefore edit that parent
+directly and is refused when editing a comment or attachment on it.
+
+That divergence is deliberate and runs in the restrictive direction (refusals,
+never a leak). The contract now says so, and — the part that matters for anyone
+tempted to "fix" it — says WHY the alternative is not merely unimplemented:
+`ISecurityService.resolveWriteScope`, the only tool a package outside
+`plugin-security` has for the parent's depth, fails OPEN, because
+`getEffectiveScope` returns `'org'` when no permission set mentions the object
+at all — indistinguishable from a genuine `modifyAllRecords` holder. Handed to a
+write gate as the depth it becomes authoritative on its own and the owner-match
+short-exits `true` for every owned row of that object. Inheriting the parent's
+edit authority starts with a depth primitive that can tell "org depth" from
+"nothing matched", not with these gates.
diff --git a/packages/plugins/plugin-audit/src/comment-access-hooks.ts b/packages/plugins/plugin-audit/src/comment-access-hooks.ts
index e37a0b6b5a..e63462f638 100644
--- a/packages/plugins/plugin-audit/src/comment-access-hooks.ts
+++ b/packages/plugins/plugin-audit/src/comment-access-hooks.ts
@@ -258,8 +258,16 @@ function withoutOperationPrivateKeys(exec: Record<string, unknown>): ExecutionCo
  * Note what deliberately did NOT change: no access DEPTH is synthesised for the
  * parent object. Absent depth leaves the sharing owner-match at its narrowest
  * (`own`) — the safe direction, and byte-for-byte the behaviour the projection
- * produced. Resolving the parent's own depth (the other candidate shape) would
- * WIDEN this gate and is a separate decision; see #7141's PR discussion. */
+ * produced.
+ *
+ * [#7144] That is now the RULED shape, not a pending question: the maintainer's
+ * ruling of 2026-08-10 keeps these gates at `own`, deliberately tighter than
+ * the parent's real edit authority. The reasoning — including the fail-open in
+ * `ISecurityService.resolveWriteScope` that makes the widening unsafe to wire
+ * today — is recorded once on the contract that owns this gate's meaning
+ * (`@objectstack/spec` — `ISharingService`, "Write DEPTH is an input the CALLER
+ * supplies"), because the `sys_attachment` kit reaches the same gate from
+ * another package; it is not restated here. */
 function callerContext(ctx: any): ExecutionContext {
   const exec = ctx?.input?.options?.context;
   if (exec && typeof exec === 'object') {
diff --git a/packages/spec/src/contracts/sharing-service.ts b/packages/spec/src/contracts/sharing-service.ts
index 34f721b68e..9534792c59 100644
--- a/packages/spec/src/contracts/sharing-service.ts
+++ b/packages/spec/src/contracts/sharing-service.ts
@@ -257,6 +257,46 @@ export type SharingWriteVerdict = 'allow' | 'abstain' | 'deny';
  * `org_user_ids`, `systemPermissions`, `posture` (ADR-0095 D2) and
  * `tabPermissions` included. Which of those a deployment makes load-bearing
  * depends on its tenancy posture, which the caller cannot know.
+ *
+ * ## Write DEPTH is an input the CALLER supplies — absent means `own` (#7144)
+ *
+ * The write gates below widen ownership "by write DEPTH" (ADR-0057 D1: `own` /
+ * `own_and_reports` / `unit` / `unit_and_below` / `org`). That depth is NOT a
+ * field of {@link ExecutionContext}, and this service never derives it: the
+ * CRUD middleware resolves it for the object of the operation IN FLIGHT and
+ * stamps it on the operation context as an operation-private (`__`-prefixed)
+ * key, which the default implementation's owner-match reads. A caller that is
+ * not that middleware hands over no depth, and the owner-match then runs at its
+ * NARROWEST — owner-only, i.e. `own`.
+ *
+ * **For the PARENT-record gates that is deliberate, not an oversight.** The
+ * `sys_comment` gates (`@objectstack/plugin-audit`) and the `sys_attachment`
+ * kit (`@objectstack/service-storage`) ask this service about the PARENT
+ * record's object while the operation in flight is on the CHILD, so the stamped
+ * depth was resolved for a different object and is dropped rather than carried
+ * across. Stated as behaviour: a caller whose write depth on the parent object
+ * is `unit` / `unit_and_below` / `org` can edit that parent directly through
+ * the CRUD path, and is REFUSED when editing or deleting a comment or
+ * attachment on it. The divergence runs in the RESTRICTIVE direction —
+ * refusals, never a leak — and the maintainer ruling of 2026-08-10 (#7144,
+ * split from #7141 / PR #7143) is that these gates STAY at `own`.
+ *
+ * **Why the obvious "fix" is off the table** — recorded here so the next reader
+ * can tell "deliberately tighter" from "nobody got round to it". Making these
+ * gates inherit the parent's real edit authority means resolving the parent's
+ * depth through the only tool a package outside `plugin-security` has,
+ * `ISecurityService.resolveWriteScope` — and that fails OPEN on one input:
+ * `getEffectiveScope` returns `'org'` when NO permission set mentions the
+ * object at all (`plugin-security/src/permission-evaluator.ts` —
+ * `if (!matched) return 'org'`), which is byte-identical to what a genuine
+ * `modifyAllRecords` holder gets. That is why the method's own doc block calls
+ * `'org'` authoritative ONLY when paired with an explicit
+ * `ISecurityService.hasWriteBypass` check. Handed to a write gate as the depth
+ * it becomes fully authoritative on its own, and the owner-match short-exits
+ * `true` for EVERY owned row of an unmatched object — a real widening, not a
+ * theoretical one. So inheriting the parent's depth starts with a depth
+ * primitive that can tell "org depth" from "nothing matched", never with these
+ * gates.
  */
 export interface ISharingService {
   /**
@@ -308,6 +348,13 @@ export interface ISharingService {
    * `modifyAllRecords` super-user bypass. Always true for system context,
    * `public` objects, and objects with no owner field.
    *
+   * [#7144] The write DEPTH in that first sentence is an INPUT this service is
+   * handed, never one it resolves — so a caller outside the CRUD middleware
+   * (the `sys_comment` and `sys_attachment` PARENT-record gates, which both
+   * reach this service through this method) matches ownership at `own`. That is
+   * the ruled shape, and the fail-open that blocks widening it is written up
+   * once in "Write DEPTH is an input the CALLER supplies" on this interface.
+   *
    * [#6428] The two-state PROJECTION of {@link checkEdit}: `true` for every
    * verdict that is not `deny`, i.e. `allow` and `abstain` alike. That
    * collapse is the historical semantics, kept byte-for-byte so existing