diff --git a/tests-bdd/features/claims-array-ers.feature b/tests-bdd/features/claims-array-ers.feature
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+@claims-array-ers @stateless
+Feature: Array-valued claims in multi-strategy ERS
+  Validate that Entity_Claims carrying array-valued claims (e.g., groups)
+  survive the full pipeline: claims provider → output mapping → flattening →
+  subject mapping evaluation → authorization decision.
+
+  Array claims require the `.groups[]` wildcard selector in subject condition
+  sets — the flattening library produces indexed keys (.groups[0], .groups[1])
+  and wildcard keys (.groups[]) but NOT a plain .groups key for arrays.
+
+  Background:
+    And an ERS configuration with mode "multi-strategy" and failure strategy "continue"
+    And an ERS provider "jwt_claims" of type "claims"
+    And an ERS mapping strategy "claims_groups" using provider "jwt_claims"
+      """
+      entity_type: subject
+      conditions:
+        jwt_claims:
+          - claim: groups
+            operator: exists
+      output_mapping:
+        - source_claim: groups
+          claim_name: groups
+        - source_claim: userName
+          claim_name: username
+      """
+    And a local platform with inline ERS configuration
+
+  Scenario: Array claim with matching element gets PERMIT
+    Given I submit a request to create a namespace with name "arr-permit.test" and reference id "ns_arr_permit"
+    And I send a request to create an attribute with:
+      | namespace_id   | name   | rule  | values                         |
+      | ns_arr_permit  | groups | anyOf | engineering,marketing,security |
+    Then the response should be successful
+    Given a condition group referenced as "cg_arr_permit" with an "or" operator with conditions:
+      | selector_value | operator | values      |
+      | .groups[]      | in       | engineering |
+    And a subject set referenced as "ss_arr_permit" containing the condition groups "cg_arr_permit"
+    And I send a request to create a subject condition set referenced as "scs_arr_permit" containing subject sets "ss_arr_permit"
+    And I send a request to create a subject mapping with:
+      | reference_id   | attribute_value                                          | condition_set_name | standard actions | custom actions |
+      | sm_arr_permit  | https://arr-permit.test/attr/groups/value/engineering    | scs_arr_permit     | read             |                |
+    Then the response should be successful
+    Given there is a claims subject entity referenced as "alice_arr" with claims:
+      """
+      {"userName":"alice","groups":["engineering","devops"]}
+      """
+    When I send a decision request for entity chain "alice_arr" for "read" action on resource "https://arr-permit.test/attr/groups/value/engineering"
+    Then the response should be successful
+    And I should get a "PERMIT" decision response
+
+  Scenario: Array claim with no matching element gets DENY
+    Given I submit a request to create a namespace with name "arr-deny.test" and reference id "ns_arr_deny"
+    And I send a request to create an attribute with:
+      | namespace_id | name   | rule  | values                         |
+      | ns_arr_deny  | groups | anyOf | engineering,marketing,security |
+    Then the response should be successful
+    Given a condition group referenced as "cg_arr_deny" with an "or" operator with conditions:
+      | selector_value | operator | values      |
+      | .groups[]      | in       | engineering |
+    And a subject set referenced as "ss_arr_deny" containing the condition groups "cg_arr_deny"
+    And I send a request to create a subject condition set referenced as "scs_arr_deny" containing subject sets "ss_arr_deny"
+    And I send a request to create a subject mapping with:
+      | reference_id | attribute_value                                        | condition_set_name | standard actions | custom actions |
+      | sm_arr_deny  | https://arr-deny.test/attr/groups/value/engineering    | scs_arr_deny       | read             |                |
+    Then the response should be successful
+    Given there is a claims subject entity referenced as "bob_arr" with claims:
+      """
+      {"userName":"bob","groups":["marketing","sales"]}
+      """
+    When I send a decision request for entity chain "bob_arr" for "read" action on resource "https://arr-deny.test/attr/groups/value/engineering"
+    Then the response should be successful
+    And I should get a "DENY" decision response
+
+  Scenario: Array claim with anyOf rule matches one of multiple attribute values
+    Given I submit a request to create a namespace with name "arr-anyof.test" and reference id "ns_arr_anyof"
+    And I send a request to create an attribute with:
+      | namespace_id  | name   | rule  | values                         |
+      | ns_arr_anyof  | groups | anyOf | engineering,marketing,security |
+    Then the response should be successful
+    Given a condition group referenced as "cg_arr_anyof" with an "or" operator with conditions:
+      | selector_value | operator | values               |
+      | .groups[]      | in       | engineering,security |
+    And a subject set referenced as "ss_arr_anyof" containing the condition groups "cg_arr_anyof"
+    And I send a request to create a subject condition set referenced as "scs_arr_anyof" containing subject sets "ss_arr_anyof"
+    And I send a request to create a subject mapping with:
+      | reference_id  | attribute_value                                         | condition_set_name | standard actions | custom actions |
+      | sm_arr_anyof  | https://arr-anyof.test/attr/groups/value/security       | scs_arr_anyof      | read             |                |
+    Then the response should be successful
+    Given there is a claims subject entity referenced as "charlie_arr" with claims:
+      """
+      {"userName":"charlie","groups":["security","devops"]}
+      """
+    When I send a decision request for entity chain "charlie_arr" for "read" action on resource "https://arr-anyof.test/attr/groups/value/security"
+    Then the response should be successful
+    And I should get a "PERMIT" decision response