diff --git a/scripts/guard-consumer-discovery-conservation.sh b/scripts/guard-consumer-discovery-conservation.sh
index 41e48cd5c..b2a02656d 100755
--- a/scripts/guard-consumer-discovery-conservation.sh
+++ b/scripts/guard-consumer-discovery-conservation.sh
@@ -749,7 +749,10 @@ while IFS=$'\t' read -r file label; do
   # The second reviewed shape (#5102) is the shared catalog's auto-vpa: a
   # Kyverno GeneratingPolicy whose spec holds only evaluation settings, one
   # apps resource rule (apiGroups, apiVersions, operations, resources) naming
-  # one deployments, daemonsets or statefulsets resource, and one generate
+  # one deployments, daemonsets or statefulsets resource, optionally a
+  # namespaceSelector that only excludes named namespaces (#5125: matchExpressions
+  # alone, each kubernetes.io/metadata.name NotIn a list of strings; a label
+  # selector is not CEL and can only narrow what triggers), and one generate
   # expression equal, whitespace aside, to the reviewed one for that resource
   # (REVIEWED_AUTO_VPA_*). That expression builds only a
   # VerticalPodAutoscaler for the triggering workload, in its own namespace,
@@ -791,7 +794,19 @@ while IFS=$'\t' read -r file label; do
           and ([.spec.evaluation | keys | .[] | select((. == "admission" or . == "generateExisting"
             or . == "synchronize" or . == "orphanDownstreamOnPolicyDelete") | not)] | length) == 0))
         and (.spec.matchConstraints | type) == "!!map"
-        and ([.spec.matchConstraints | keys | .[] | select(. != "resourceRules")] | length) == 0
+        and ([.spec.matchConstraints | keys | .[] | select((. == "resourceRules"
+          or . == "namespaceSelector") | not)] | length) == 0
+        and ((.spec.matchConstraints | has("namespaceSelector") | not)
+          or ((.spec.matchConstraints.namespaceSelector | type) == "!!map"
+            and ([.spec.matchConstraints.namespaceSelector | keys | .[] | select(. != "matchExpressions")] | length) == 0
+            and (.spec.matchConstraints.namespaceSelector.matchExpressions | type) == "!!seq"
+            and (.spec.matchConstraints.namespaceSelector.matchExpressions | length) > 0
+            and ([.spec.matchConstraints.namespaceSelector.matchExpressions[] | select(type != "!!map"
+              or ([keys | .[] | select((. == "key" or . == "operator" or . == "values") | not)] | length) != 0
+              or (.key | type) != "!!str" or .key != "kubernetes.io/metadata.name"
+              or (.operator | type) != "!!str" or .operator != "NotIn"
+              or (.values | type) != "!!seq" or (.values | length) == 0
+              or ([.values[] | select(type != "!!str")] | length) != 0)] | length) == 0))
         and (.spec.matchConstraints.resourceRules | type) == "!!seq"
         and (.spec.matchConstraints.resourceRules | length) == 1
         and (.spec.matchConstraints.resourceRules[0] | type) == "!!map"
diff --git a/scripts/tests/crossplane-egress-policy-rules.yaml b/scripts/tests/crossplane-egress-policy-rules.yaml
index f64430b77..d2f6b7c02 100644
--- a/scripts/tests/crossplane-egress-policy-rules.yaml
+++ b/scripts/tests/crossplane-egress-policy-rules.yaml
@@ -644,7 +644,10 @@ rules:
   # policies/best-practices/auto-vpa-generating-policy.yaml): a
   # GeneratingPolicy whose spec holds only evaluation settings, one apps
   # resource rule (apiGroups, apiVersions, operations, resources) naming one
-  # deployments, daemonsets or statefulsets resource, and one generate
+  # deployments, daemonsets or statefulsets resource, optionally (#5125) a
+  # namespaceSelector whose only field is matchExpressions, each
+  # kubernetes.io/metadata.name NotIn a list of names (a label selector is not
+  # CEL and can only narrow which workloads trigger it), and one generate
   # expression that equals the catalog's expression for that resource once
   # spaces, tabs and line breaks are removed from both. Every other spec field
   # is refused, because variables and matchConditions are CEL that can read or
@@ -707,7 +710,20 @@ rules:
           'admission', 'generateExisting', 'synchronize',
           'orphanDownstreamOnPolicyDelete'])) &&
        has(object.spec.matchConstraints) &&
-       object.spec.matchConstraints.all(key, key == 'resourceRules') &&
+       object.spec.matchConstraints.all(key,
+         key in ['resourceRules', 'namespaceSelector']) &&
+       (!has(object.spec.matchConstraints.namespaceSelector) ||
+        (object.spec.matchConstraints.namespaceSelector.all(key,
+           key == 'matchExpressions') &&
+         has(object.spec.matchConstraints.namespaceSelector.matchExpressions) &&
+         object.spec.matchConstraints.namespaceSelector.matchExpressions.size() > 0 &&
+         object.spec.matchConstraints.namespaceSelector.matchExpressions.all(expression,
+           expression.all(key, key in ['key', 'operator', 'values']) &&
+           has(expression.key) &&
+           expression.key == 'kubernetes.io/metadata.name' &&
+           has(expression.operator) && expression.operator == 'NotIn' &&
+           has(expression.values) && expression.values.size() > 0 &&
+           expression.values.all(value, type(value) == string)))) &&
        has(object.spec.matchConstraints.resourceRules) &&
        object.spec.matchConstraints.resourceRules.size() == 1 &&
        object.spec.matchConstraints.resourceRules[0].all(key, key in [
diff --git a/scripts/tests/test-crossplane-egress-policy.sh b/scripts/tests/test-crossplane-egress-policy.sh
index 336df9f1e..e2d57e0fd 100755
--- a/scripts/tests/test-crossplane-egress-policy.sh
+++ b/scripts/tests/test-crossplane-egress-policy.sh
@@ -1175,6 +1175,76 @@ assert_helm_rules_accept \
   "${auto_vpa_one_line_fixture}" \
   'a reviewed GeneratingPolicy that differs only in whitespace is the reviewed exception'
 
+# #5125: a namespaceSelector that only excludes named namespaces keeps the
+# reviewed shape; every other selector form voids it.
+auto_vpa_namespace_exclusion_fixture="${auto_vpa_generating_policy_fixture/  matchConstraints:
+/  matchConstraints:
+    namespaceSelector:
+      matchExpressions:
+        - key: kubernetes.io/metadata.name
+          operator: NotIn
+          values: [\"kube-system\", \"kube-public\", \"kube-node-lease\", \"kyverno\"]
+}"
+[ "${auto_vpa_namespace_exclusion_fixture}" != "${auto_vpa_generating_policy_fixture}" ] ||
+  fail 'the namespace-excluded GeneratingPolicy must differ from the reviewed one'
+assert_helm_rules_accept \
+  'auto-vpa-generating-policy-namespace-exclusion' \
+  "${auto_vpa_namespace_exclusion_fixture}" \
+  'a reviewed GeneratingPolicy that excludes named namespaces is the reviewed exception'
+
+assert_namespace_exclusion_variant_rejected() {
+  local fixture_name="$1"
+  local fixture_body="$2"
+  local failure_message="$3"
+
+  [ "${fixture_body}" != "${auto_vpa_namespace_exclusion_fixture}" ] ||
+    fail "${fixture_name}: the variant must differ from the namespace-excluded GeneratingPolicy"
+  assert_helm_rules_reject \
+    "${fixture_name}" \
+    "${fixture_body}" \
+    "${failure_message}" \
+    'reject-cel-policy-producers'
+}
+
+assert_namespace_exclusion_variant_rejected \
+  'generating-policy-namespace-empty-expressions' \
+  "${auto_vpa_namespace_exclusion_fixture/      matchExpressions:
+        - key: kubernetes.io\/metadata.name
+          operator: NotIn
+          values: \[\"kube-system\", \"kube-public\", \"kube-node-lease\", \"kyverno\"\]/      matchExpressions: []}" \
+  'a namespaceSelector with no expressions must void the reviewed GeneratingPolicy shape'
+assert_namespace_exclusion_variant_rejected \
+  'generating-policy-namespace-match-labels' \
+  "${auto_vpa_namespace_exclusion_fixture/      matchExpressions:/      matchLabels:
+        team: platform
+      matchExpressions:}" \
+  'a namespaceSelector with matchLabels must void the reviewed GeneratingPolicy shape'
+assert_namespace_exclusion_variant_rejected \
+  'generating-policy-namespace-in-operator' \
+  "${auto_vpa_namespace_exclusion_fixture/operator: NotIn/operator: In}" \
+  'a namespaceSelector that selects namespaces must void the reviewed GeneratingPolicy shape'
+assert_namespace_exclusion_variant_rejected \
+  'generating-policy-namespace-exists-operator' \
+  "${auto_vpa_namespace_exclusion_fixture/operator: NotIn/operator: Exists}" \
+  'an Exists namespaceSelector must void the reviewed GeneratingPolicy shape'
+assert_namespace_exclusion_variant_rejected \
+  'generating-policy-namespace-other-key' \
+  "${auto_vpa_namespace_exclusion_fixture/key: kubernetes.io\/metadata.name/key: team}" \
+  'a namespaceSelector on another label must void the reviewed GeneratingPolicy shape'
+assert_namespace_exclusion_variant_rejected \
+  'generating-policy-namespace-empty-values' \
+  "${auto_vpa_namespace_exclusion_fixture/values: \[\"kube-system\", \"kube-public\", \"kube-node-lease\", \"kyverno\"\]/values: []}" \
+  'a namespaceSelector with no values must void the reviewed GeneratingPolicy shape'
+assert_reviewed_generation_variant_rejected \
+  'generating-policy-object-selector' \
+  "${auto_vpa_generating_policy_fixture/  matchConstraints:
+/  matchConstraints:
+    objectSelector:
+      matchLabels:
+        app: x
+}" \
+  'an objectSelector must void the reviewed GeneratingPolicy shape'
+
 helm_admin_network_policy_fixture=$'apiVersion: policy.networking.k8s.io/v1alpha1\nkind: AdminNetworkPolicy\nmetadata:\n  name: crossplane-world-egress\nspec:\n  priority: 10\n  subject:\n    namespaces:\n      matchLabels:\n        kubernetes.io/metadata.name: crossplane-system\n  egress:\n  - name: allow-world\n    action: Allow\n    to:\n    - networks: [0.0.0.0/0]'
 assert_helm_rules_reject \
   'helm-crossplane-admin-network-policy' \
diff --git a/scripts/tests/test-guard-consumer-discovery-conservation.sh b/scripts/tests/test-guard-consumer-discovery-conservation.sh
index df1a7d28a..2aa0a7437 100755
--- a/scripts/tests/test-guard-consumer-discovery-conservation.sh
+++ b/scripts/tests/test-guard-consumer-discovery-conservation.sh
@@ -1221,6 +1221,32 @@ YAML
     { printf 'FAIL: the one-line variant did not change the reviewed GeneratingPolicy\n' >&2; failures=$((failures + 1)); }
   printf '  - cel-generation.yaml\n' >>"$root/k8s/providers/prod/apps/kustomization.yaml"
   expect_pass 'the reviewed auto-vpa GeneratingPolicy on one line does not alter consumers' "$root" '2 consumer(s)'
+  # #5125: a NotIn exclusion of named namespaces passes too; a label selector
+  # only narrows which workloads the policy reacts to.
+  root="$(fixture reviewed-cel-generation-namespace-exclusion)"
+  yq '.spec.matchConstraints.namespaceSelector = {"matchExpressions": [{"key": "kubernetes.io/metadata.name", "operator": "NotIn", "values": ["kube-system", "kube-public", "kube-node-lease", "kyverno"]}]}' \
+    "$WORK/reviewed-cel-generation/k8s/providers/prod/apps/cel-generation.yaml" >"$root/k8s/providers/prod/apps/cel-generation.yaml"
+  printf '  - cel-generation.yaml\n' >>"$root/k8s/providers/prod/apps/kustomization.yaml"
+  expect_pass 'the reviewed auto-vpa GeneratingPolicy with a namespace exclusion does not alter consumers' "$root" '2 consumer(s)'
+  for target in match-labels in-operator exists-operator other-key object-selector empty-expressions empty-values non-string-value extra-expression-key; do
+    root="$(fixture "reviewed-cel-generation-namespace-exclusion-$target")"
+    cp "$WORK/reviewed-cel-generation-namespace-exclusion/k8s/providers/prod/apps/cel-generation.yaml" "$root/k8s/providers/prod/apps/cel-generation.yaml"
+    case "$target" in
+      match-labels) yq -i '.spec.matchConstraints.namespaceSelector.matchLabels = {"team": "platform"}' "$root/k8s/providers/prod/apps/cel-generation.yaml" ;;
+      in-operator) yq -i '.spec.matchConstraints.namespaceSelector.matchExpressions[0].operator = "In"' "$root/k8s/providers/prod/apps/cel-generation.yaml" ;;
+      exists-operator) yq -i '.spec.matchConstraints.namespaceSelector.matchExpressions[0] |= (.operator = "Exists" | del(.values))' "$root/k8s/providers/prod/apps/cel-generation.yaml" ;;
+      other-key) yq -i '.spec.matchConstraints.namespaceSelector.matchExpressions[0].key = "team"' "$root/k8s/providers/prod/apps/cel-generation.yaml" ;;
+      object-selector) yq -i '.spec.matchConstraints.objectSelector = {"matchLabels": {"app": "x"}}' "$root/k8s/providers/prod/apps/cel-generation.yaml" ;;
+      empty-expressions) yq -i '.spec.matchConstraints.namespaceSelector.matchExpressions = []' "$root/k8s/providers/prod/apps/cel-generation.yaml" ;;
+      empty-values) yq -i '.spec.matchConstraints.namespaceSelector.matchExpressions[0].values = []' "$root/k8s/providers/prod/apps/cel-generation.yaml" ;;
+      non-string-value) yq -i '.spec.matchConstraints.namespaceSelector.matchExpressions[0].values += [{"name": "x"}]' "$root/k8s/providers/prod/apps/cel-generation.yaml" ;;
+      extra-expression-key) yq -i '.spec.matchConstraints.namespaceSelector.matchExpressions[0].extra = "x"' "$root/k8s/providers/prod/apps/cel-generation.yaml" ;;
+    esac
+    cmp -s "$WORK/reviewed-cel-generation-namespace-exclusion/k8s/providers/prod/apps/cel-generation.yaml" "$root/k8s/providers/prod/apps/cel-generation.yaml" &&
+      { printf 'FAIL: the %s variant did not change the namespace-excluded GeneratingPolicy\n' "$target" >&2; failures=$((failures + 1)); }
+    printf '  - cel-generation.yaml\n' >>"$root/k8s/providers/prod/apps/kustomization.yaml"
+    expect_refusal "a $target namespace selector is outside the reviewed shape" "$root" 'unevaluated CEL admission mutation' 'consumers are UNKNOWN'
+  done
   for target in network-policy-kind source-api-version namespace-trigger extra-group variables resource-clone workload-clone computed-key escaped-key label-read generated-deployment unbound-apps-kind unbound-target-ref other-target-name literal-apply-namespace literal-object-namespace mismatched-trigger second-generation match-conditions foreign-group split-literal delete-operation any-version; do
     root="$(fixture "reviewed-cel-generation-$target")"
     cp "$WORK/reviewed-cel-generation/k8s/providers/prod/apps/cel-generation.yaml" "$root/k8s/providers/prod/apps/cel-generation.yaml"