diff --git a/.changeset/systemfields-drop-owner-key.md b/.changeset/systemfields-drop-owner-key.md
new file mode 100644
index 0000000000..7901cc8f9f
--- /dev/null
+++ b/.changeset/systemfields-drop-owner-key.md
@@ -0,0 +1,18 @@
+---
+"@objectstack/spec": minor
+---
+
+fix(spec): drop the dead `systemFields.owner` key (#3175 follow-up)
+
+`ObjectSchema.systemFields` exposed an `owner?: boolean` opt-out key that nothing
+read — the registry (`applySystemFields`) only consumes `systemFields.tenant` and
+`systemFields.audit`, and `owner_id` provisioning is governed by the object-level
+`ownership` property (`'user' | 'org' | 'none'`, made first-class in #3185). The
+key was declared but wired to nothing.
+
+Removed it so the schema only advertises the two opt-outs it actually honors
+(`tenant`, `audit`). Backward-compatible at runtime: the key was ignored before and
+is stripped now (both no-ops). A TypeScript author who set `systemFields.owner`
+will now see an excess-property error — the fix is to delete the key (it never did
+anything) or use `ownership: 'org' | 'none'` to skip `owner_id`. Also corrected the
+stale `objectql/security` doc that called `audit` "reserved" (it is active).
diff --git a/content/docs/protocol/objectql/security.mdx b/content/docs/protocol/objectql/security.mdx
index 64e3f077f2..0f71a5002e 100644
--- a/content/docs/protocol/objectql/security.mdx
+++ b/content/docs/protocol/objectql/security.mdx
@@ -405,7 +405,7 @@ Combine OWD (`sharingModel: private`), an RLS `using` policy, FLS (`readable: fa
 
 ### Security by Default
 
-Leave registry-level `systemFields` injection enabled (the object default) so multi-tenant objects auto-stamp `organization_id` on create, and use field `defaultValue` to seed ownership fields — so records are never left unscoped. (`owner`/`audit` injection keys on `systemFields` are reserved for future expansion; only `tenant` is active today — see `packages/spec/src/data/object.zod.ts`.)
+Leave registry-level `systemFields` injection enabled (the object default) so multi-tenant objects auto-stamp `organization_id` on create, and use field `defaultValue` to seed ownership fields — so records are never left unscoped. (`systemFields` accepts two opt-out keys — `tenant` and `audit` — both active; `owner_id` provisioning is governed separately by the object-level `ownership` property. See `packages/spec/src/data/object.zod.ts`.)
 
 ---
 
diff --git a/content/docs/references/data/object.mdx b/content/docs/references/data/object.mdx
index 66116bafda..f84e4110fe 100644
--- a/content/docs/references/data/object.mdx
+++ b/content/docs/references/data/object.mdx
@@ -107,7 +107,7 @@ const result = ApiMethod.parse(data);
 | **managedBy** | `Enum<'platform' \| 'config' \| 'system' \| 'append-only' \| 'better-auth'>` | optional | Lifecycle bucket — platform (user CRUD) \| config (admin authored) \| system (engine-managed) \| append-only (audit) \| better-auth (identity). UI clients honour the resolved affordance matrix. |
 | **ownership** | `Enum<'user' \| 'org' \| 'none'>` | optional | Record-ownership model: user (default — injects reassignable owner_id) \| org \| none (no per-record owner, skips owner_id). Distinct from the package own/extend contribution kind. |
 | **userActions** | `{ create?: boolean; import?: boolean; edit?: boolean \| { enabled?: boolean; visibleWhen?: string \| { dialect: Enum<'cel' \| 'js' \| 'cron' \| 'template'>; source?: string; ast?: any; meta?: object }; disabledWhen?: string \| { dialect: Enum<'cel' \| 'js' \| 'cron' \| 'template'>; source?: string; ast?: any; meta?: object } }; delete?: boolean \| { enabled?: boolean; visibleWhen?: string \| { dialect: Enum<'cel' \| 'js' \| 'cron' \| 'template'>; source?: string; ast?: any; meta?: object }; disabledWhen?: string \| { dialect: Enum<'cel' \| 'js' \| 'cron' \| 'template'>; source?: string; ast?: any; meta?: object } }; … }` | optional | Per-object override of the resolved CRUD affordance matrix. |
-| **systemFields** | `'false' \| { tenant?: boolean; owner?: boolean; audit?: boolean }` | optional | Opt out of, or selectively disable, registry-level system-field auto-injection. |
+| **systemFields** | `'false' \| { tenant?: boolean; audit?: boolean }` | optional | Opt out of, or selectively disable, registry-level system-field auto-injection. |
 | **datasource** | `string` | optional | Target Datasource ID. "default" is the primary DB. |
 | **external** | `{ remoteName?: string; remoteSchema?: string; writable?: boolean; columnMap?: Record<string, string>; … }` | optional | Remote table binding for federated (external) objects. |
 | **fields** | `Record<string, { name?: string; label?: string; type: Enum<'text' \| 'textarea' \| 'email' \| 'url' \| 'phone' \| 'password' \| 'secret' \| 'markdown' \| 'html' \| 'richtext' \| 'number' \| 'currency' \| 'percent' \| 'date' \| 'datetime' \| 'time' \| 'boolean' \| 'toggle' \| 'select' \| 'multiselect' \| 'radio' \| 'checkboxes' \| 'lookup' \| 'master_detail' \| 'tree' \| 'user' \| 'image' \| 'file' \| 'avatar' \| 'video' \| 'audio' \| 'formula' \| 'summary' \| 'autonumber' \| 'composite' \| 'repeater' \| 'record' \| 'location' \| 'address' \| 'code' \| 'json' \| 'color' \| 'rating' \| 'slider' \| 'signature' \| 'qrcode' \| 'progress' \| 'tags' \| 'vector'>; description?: string; … }>` | ✅ | Field definitions map. Keys must be snake_case identifiers. |
diff --git a/packages/spec/src/data/object.zod.ts b/packages/spec/src/data/object.zod.ts
index cba76139d2..acd3772e86 100644
--- a/packages/spec/src/data/object.zod.ts
+++ b/packages/spec/src/data/object.zod.ts
@@ -695,7 +695,6 @@ const ObjectSchemaBase = z.object({
       z.literal(false),
       z.object({
         tenant: z.boolean().optional().describe('Inject the organization_id column. Default true (the column is always provisioned; the multi-tenant flag governs only its index).'),
-        owner: z.boolean().optional().describe('Unwired: owner_id provisioning is governed by the object-level `ownership` property (`user`/`org`/`none`), not this key. Reserved.'),
         audit: z.boolean().optional().describe('Inject the audit columns (created_at/created_by/updated_at/updated_by). Default true.'),
       }),
     ])