diff --git a/docs/evidence/namespace-ownership.yaml b/docs/evidence/namespace-ownership.yaml
index 4b200049..a5f8f529 100644
--- a/docs/evidence/namespace-ownership.yaml
+++ b/docs/evidence/namespace-ownership.yaml
@@ -1,6 +1,10 @@
 # Namespace → owner/service mapping for CUST-WP-0071-T01.
 # Unknown namespaces stay unknown; do not invent tenants.
 namespaces:
+  # Source-reviewed 2026-10-19; references in CUST-WP-0071 ownership follow-up.
+  mas: {owner: mail-address-semantics, service: mas-live-test, tenant: unknown}
+  playwright: {owner: railiance-platform, service: rapp-playwright, tenant: unknown}
+  rapp-qonto: {owner: rapp-qonto, service: qonto, tenant: unknown}
   knative-serving: {owner: rail-knative, service: knative-serving, tenant: unknown}
   kourier-system: {owner: rail-knative, service: kourier, tenant: unknown}
   argocd: {owner: railiance-enablement, service: argocd, tenant: unknown}
diff --git a/workplans/CUST-WP-0071-measured-workload-sizing-and-weekly-review.md b/workplans/CUST-WP-0071-measured-workload-sizing-and-weekly-review.md
index 66943dae..2f394aca 100644
--- a/workplans/CUST-WP-0071-measured-workload-sizing-and-weekly-review.md
+++ b/workplans/CUST-WP-0071-measured-workload-sizing-and-weekly-review.md
@@ -493,3 +493,17 @@ unvalidated under shared contention. T02 stays progress while the owner extends
 the same configurable harness with edits, startup/restart and burst phases.
 Actual deployed-release/hardware and shared-service observations remain required
 for the final allocation review; attended human acceptance remains separate.
+
+### Namespace ownership follow-up
+
+The three unknown namespace owners in the 12:50 snapshot now have source-backed
+routes in `docs/evidence/namespace-ownership.yaml`: `mas` belongs to
+mail-address-semantics (`deploy/railiance/manifests.yaml`, MAS-WP-0003; retirement
+is separately tracked in MAS-WP-0007); `playwright` lifecycle belongs to
+railiance-platform with package implementation in rapp-playwright
+(`railiance-platform/docs/playwright-consumer-access.md`, source `53d34bc4`);
+`rapp-qonto` is the runtime package for qonto-assistant
+(`rapp-qonto/declarations/rapp.yaml` and `runtime/knative/namespace.yaml`, source
+`7537e056`). No tenant is inferred. The retained capture and its map hash stay
+unchanged; the next reconciliation consumes this improved map. This identifies
+receiving owners, not measured demand or authorization to retire workloads.