diff --git a/src/proto_alpha/lib_plugin/RPC.ml b/src/proto_alpha/lib_plugin/RPC.ml
index 4014e166d12a0e2a54e325dd60560c2195b03573..b2d0b93dd18396ab5adee7f22210910357983932 100644
--- a/src/proto_alpha/lib_plugin/RPC.ml
+++ b/src/proto_alpha/lib_plugin/RPC.ml
@@ -4001,7 +4001,9 @@ module Validators = struct
       RPC_service.get_service
         ~description:
           "Retrieves the level, the attestation slots and the public key hash \
-           of each delegate allowed to attest a block.\n\
+           of each delegate allowed to attest a block. Also returns each \
+           delegate's current consensus key, and current companion key when \
+           needed for crafting and validating attestations at this level.\n\
            By default, it provides this information for the next level.\n\
            Parameter `level` can be used to specify the (valid) level(s) in \
            the past or future at which the attestation rights have to be \
@@ -4016,9 +4018,15 @@ module Validators = struct
   let add_attestation_slots_at_level (ctxt, acc) level =
     let open Lwt_result_syntax in
     let+ ctxt, rights = Baking.attesting_rights ctxt level in
+    let aggregate_attestation = Constants.aggregate_attestation ctxt in
     ( ctxt,
       Signature.Public_key_hash.Map.fold
         (fun _pkh {Baking.delegate; consensus_key; companion_key; slots} acc ->
+          let companion_key =
+            match consensus_key with
+            | Bls _ when aggregate_attestation -> companion_key
+            | _ -> None
+          in
           {level = level.level; delegate; consensus_key; companion_key; slots}
           :: acc)
         rights
diff --git a/tezt/tests/companion_key.ml b/tezt/tests/companion_key.ml
index 43808c870d38456a04328ad1088be2de153976d3..0b9b46f2865892f2e74f0bfd5b25a538ebaa80af 100644
--- a/tezt/tests/companion_key.ml
+++ b/tezt/tests/companion_key.ml
@@ -124,6 +124,7 @@ let init_node_and_client ~protocol =
       (["cache_sampler_state_cycles"], `Int (consensus_rights_delay + 3));
       (["cache_stake_distribution_cycles"], `Int (consensus_rights_delay + 3));
       (["allow_tz4_delegate_enable"], `Bool true);
+      (["aggregate_attestation"], `Bool true);
     ]
   in
   let* parameter_file =
@@ -200,10 +201,10 @@ let test_update_companion_key =
   in
   unit
 
-let test_update_companion_key_without_consensus_key =
+let test_update_companion_key_for_non_tz4_delegate =
   Protocol.register_regression_test
     ~__FILE__
-    ~title:"update companion key without updating consensus key"
+    ~title:"update companion key for non tz4 delegate"
     ~tags:[team; "companion_key"]
     ~supports:(Protocol.From_protocol 023)
   @@ fun protocol ->
@@ -225,6 +226,76 @@ let test_update_companion_key_without_consensus_key =
   Log.info "Waiting for companion key activation" ;
   let* () = bake_n_cycles (consensus_rights_delay + 1) client in
 
+  Log.info "Checking key is activated" ;
+  let* () =
+    check_companion_key
+      ~__LOC__
+      delegate
+      ~expected_active:companion_key_bls
+      client
+  in
+  let* () =
+    check_validators_companion_key ~__LOC__ delegate ~expected:None client
+  in
+  let* current_level = get_current_level client in
+  let* () =
+    check_validators_companion_key
+      ~__LOC__
+      ~level:(current_level.level + 1)
+      delegate
+      ~expected:None
+      client
+  in
+  unit
+
+let test_update_companion_key_for_tz4_delegate =
+  Protocol.register_regression_test
+    ~__FILE__
+    ~title:"update companion key for tz4 delegate"
+    ~tags:[team; "companion_key"]
+    ~supports:(Protocol.From_protocol 023)
+  @@ fun protocol ->
+  let* _node, client = init_node_and_client ~protocol in
+  (* gen keys delegate -s bls *)
+  (* transfer 1000000 from bootstrap2 to delegate *)
+  let* delegate =
+    Client.gen_and_show_keys ~alias:"delegate" ~sig_alg:"bls" client
+  in
+  let* () =
+    Client.transfer
+      ~burn_cap:Tez.one
+      ~amount:(Tez.of_int 1_000_000)
+      ~giver:Constant.bootstrap2.alias
+      ~receiver:delegate.public_key_hash
+      client
+  in
+  let* () = Client.bake_for_and_wait client in
+  (* set delegate for delegate to delegate *)
+  let*! () =
+    Client.set_delegate ~src:delegate.alias ~delegate:delegate.alias client
+  in
+  let* () = Client.bake_for_and_wait client in
+  (* stake 800000 for delegate *)
+  let* () = Client.stake ~staker:delegate.alias (Tez.of_int 800_000) client in
+  let* () = Client.bake_for_and_wait client in
+  (* gen keys companion_key -s bls *)
+  (* set companion key for delegate to companion_key *)
+  let* companion_key_bls =
+    Client.gen_and_show_keys ~alias:"companion_key" ~sig_alg:"bls" client
+  in
+  Log.info "Updating companion key" ;
+  let* () =
+    Client.update_companion_key
+      ~hooks
+      ~src:delegate.alias
+      ~pk:companion_key_bls.alias
+      client
+  in
+  let* () = Client.bake_for_and_wait client in
+
+  Log.info "Waiting for companion key activation" ;
+  let* () = bake_n_cycles (consensus_rights_delay + 1) client in
+
   Log.info "Checking key is activated" ;
   let* () =
     check_companion_key
@@ -249,4 +320,5 @@ let test_update_companion_key_without_consensus_key =
 
 let register ~protocols =
   test_update_companion_key protocols ;
-  test_update_companion_key_without_consensus_key protocols
+  test_update_companion_key_for_non_tz4_delegate protocols ;
+  test_update_companion_key_for_tz4_delegate protocols
diff --git a/tezt/tests/expected/companion_key.ml/Alpha- update companion key without updating consensus key.out b/tezt/tests/expected/companion_key.ml/Alpha- update companion key for non tz4 delegate.out
similarity index 100%
rename from tezt/tests/expected/companion_key.ml/Alpha- update companion key without updating consensus key.out
rename to tezt/tests/expected/companion_key.ml/Alpha- update companion key for non tz4 delegate.out
diff --git a/tezt/tests/expected/companion_key.ml/Alpha- update companion key for tz4 delegate.out b/tezt/tests/expected/companion_key.ml/Alpha- update companion key for tz4 delegate.out
new file mode 100644
index 0000000000000000000000000000000000000000..a066d8363849737d2c5ef16db6b44f08d2722945
--- /dev/null
+++ b/tezt/tests/expected/companion_key.ml/Alpha- update companion key for tz4 delegate.out	
@@ -0,0 +1,27 @@
+
+./octez-client --wait none set companion key for delegate to companion_key
+Node is bootstrapped.
+Estimated gas: 3249.100 units (will add 100 for safety)
+Estimated storage: no bytes added
+Operation successfully injected in the node.
+Operation hash is '[OPERATION_HASH]'
+NOT waiting for the operation to be included.
+Use command
+  octez-client wait for [OPERATION_HASH] to be included --confirmations 1 --branch [BLOCK_HASH]
+and/or an external block explorer to make sure that it has been included.
+This sequence of operations was run:
+  Manager signed operations:
+    From: [PUBLIC_KEY_HASH]
+    Fee to the baker: ꜩ0.000743
+    Expected counter: 5
+    Gas limit: 3350
+    Storage limit: 0 bytes
+    Balance updates:
+      [PUBLIC_KEY_HASH] ... -ꜩ0.000743
+      payload fees(the block proposer) ....... +ꜩ0.000743
+    Update_companion_key:
+      Public key hash: [PUBLIC_KEY_HASH]
+      Proof of possession: [BLS_SIGNATURE]
+      This companion key update was successfully applied
+      Consumed gas: 3249.030
+