diff --git a/src/lib_shell/prevalidation.ml b/src/lib_shell/prevalidation.ml
index dc083748512baeea5acf9eb2be1425bd13f7b9bd..5fb8dae5f3449e606787950c44ce10b7359a09e7 100644
--- a/src/lib_shell/prevalidation.ml
+++ b/src/lib_shell/prevalidation.ml
@@ -134,11 +134,20 @@ module MakeAbstract
 
   type operation = protocol_operation Shell_operation.operation
 
+  module Manager = Signature.Public_key_hash
+
   type t = {
     validation_info : Proto.Mempool.validation_info;
+        (** Static information needed by [Proto.Mempool.add_operation]. *)
     mempool : Proto.Mempool.t;
+        (** Protocol representation of currently valid operations. *)
     bounding_state : Bounding.state;
+        (** Representation of currently valid operations used to enforce
+            mempool bounds. *)
+    manager_map : protocol_operation Manager.Map.t;
+        (** Valid manager operations in the mempool, indexed by manager. *)
     filter_info : Filter.Mempool.filter_info;
+        (** Static information needed by [Filter.Mempool.pre_filter]. *)
   }
 
   let create_aux ?old_state chain_store head timestamp =
@@ -161,8 +170,9 @@ module MakeAbstract
       | None -> Filter.Mempool.init context ~head
       | Some old_state -> Filter.Mempool.flush old_state.filter_info ~head
     in
-    return
-      {validation_info; mempool; bounding_state = Bounding.empty; filter_info}
+    let bounding_state = Bounding.empty in
+    let manager_map = Manager.Map.empty in
+    return {validation_info; mempool; bounding_state; manager_map; filter_info}
 
   let create chain_store ~head ~timestamp =
     create_aux chain_store head timestamp
@@ -273,6 +283,38 @@ module MakeAbstract
     in
     return (mempool, bounding_state, replacements)
 
+  (* Update the [manager_map] by removing the [replacements] then
+     adding [op] if it is a manager operation. Non-manager operations
+     are ignored.
+
+     Note that it is important to remove before adding, otherwise we
+     risk removing the newly added operation if it has just replaced
+     an operation from the same manager.
+
+     [mempool_before] is the protocol's mempool representation before
+     calling [Proto.Mempool.add_operation], so that it still contains
+     the replaced operations. Indeed, it is used to retrieve these
+     operations from their hash. *)
+  let update_manager_map manager_map mempool_before op replacements =
+    let manager_map =
+      (* No need to call [Proto.Mempool.operations] when the list is empty. *)
+      if List.is_empty replacements then manager_map
+      else
+        let ops = Proto.Mempool.operations mempool_before in
+        let remove_replacement mmap (oph, _error_classification) =
+          match Operation_hash.Map.find oph ops with
+          | None -> (* This case should never happen. *) mmap
+          | Some op -> (
+              match Filter.Mempool.find_manager op with
+              | None -> (* Not a manager operation: ignore it. *) mmap
+              | Some manager -> Manager.Map.remove manager mmap)
+        in
+        List.fold_left remove_replacement manager_map replacements
+    in
+    match Filter.Mempool.find_manager op.protocol with
+    | None -> (* Not a manager operation: ignore it. *) manager_map
+    | Some manager -> Manager.Map.add manager op.protocol manager_map
+
   let add_operation_result state (filter_config, bounding_config) op :
       add_result tzresult Lwt.t =
     let open Lwt_result_syntax in
@@ -295,9 +337,12 @@ module MakeAbstract
         valid_op
     in
     match res with
-    | Ok (mempool, bounding_state, replacement) ->
-        let state = {state with mempool; bounding_state} in
-        return (state, valid_op, `Prechecked, replacement)
+    | Ok (mempool, bounding_state, replacements) ->
+        let manager_map =
+          update_manager_map state.manager_map state.mempool op replacements
+        in
+        let state = {state with mempool; bounding_state; manager_map} in
+        return (state, valid_op, `Prechecked, replacements)
     | Error trace ->
         (* We convert any error from [check_conflict_and_bound] into an
            [add_result] here, rather than let [add_operation] below do
diff --git a/src/lib_shell/shell_plugin.ml b/src/lib_shell/shell_plugin.ml
index 7a7782a68a1b104b4fe63d52add2c57cee7d1e4f..bfadbb231fcef03f9408c329bc164ef8f6cce1be 100644
--- a/src/lib_shell/shell_plugin.ml
+++ b/src/lib_shell/shell_plugin.ml
@@ -56,6 +56,8 @@ module type FILTER = sig
 
     val conflict_handler : config -> Proto.Mempool.conflict_handler
 
+    val find_manager : Proto.operation -> Signature.Public_key_hash.t option
+
     val fee_needed_to_overtake :
       op_to_overtake:Proto.operation ->
       candidate_op:Proto.operation ->
@@ -94,6 +96,8 @@ module No_filter (Proto : Registered_protocol.T) :
         `Replace
       else `Keep
 
+    let find_manager _ = None
+
     let fee_needed_to_overtake ~op_to_overtake:_ ~candidate_op:_ = None
   end
 end
diff --git a/src/lib_shell/shell_plugin.mli b/src/lib_shell/shell_plugin.mli
index 465ffe3946b551dcbbe24cf6a888ec514b4475de..735b40eceeff94909b2737457c6a7a6aaa0ec498 100644
--- a/src/lib_shell/shell_plugin.mli
+++ b/src/lib_shell/shell_plugin.mli
@@ -88,6 +88,10 @@ module type FILTER = sig
         implementation of this function relies). *)
     val conflict_handler : config -> Proto.Mempool.conflict_handler
 
+    (** If the operation is a manager operation, return its source,
+        otherwise return [None]. *)
+    val find_manager : Proto.operation -> Signature.Public_key_hash.t option
+
     (** Compute the minimal fee (expressed in mutez) that [candidate_op]
         would need to have in order to be strictly greater than
         [op_to_overtake] according to {!Proto.compare_operations}.
diff --git a/src/lib_shell/test/test_prevalidation.ml b/src/lib_shell/test/test_prevalidation.ml
index 9d341078b880e9661d75483b4f80dc3b886a224d..6b6b51ca6120b347d26eb7717a57b3b3fdcbd7c0 100644
--- a/src/lib_shell/test/test_prevalidation.ml
+++ b/src/lib_shell/test/test_prevalidation.ml
@@ -31,6 +31,15 @@
     Subject:      Unit tests for {!Prevalidation.T}
 *)
 
+(* Note: the logic of Prevalidation.t.manager_map is not tested here
+   because the mock protocol operations don't have a notion of
+   manager. However, it will serve to indicate the fees needed to
+   replace the previous operation in a manager conflict error, which
+   will be tested in tezt. *)
+(* TODO: https://gitlab.com/tezos/tezos/-/issues/5197
+   Update the comment above once the fees needed to replace are
+   implemented and tested. *)
+
 let register_test ~title ~additional_tags =
   Test.register
     ~__FILE__
diff --git a/src/proto_016_PtMumbai/lib_plugin/mempool.ml b/src/proto_016_PtMumbai/lib_plugin/mempool.ml
index 1bd7893fcbcf415b5fa5892821533aa704656fcf..2fe3a73d26ed07258f583e901a267aaf76c4b78f 100644
--- a/src/proto_016_PtMumbai/lib_plugin/mempool.ml
+++ b/src/proto_016_PtMumbai/lib_plugin/mempool.ml
@@ -616,6 +616,18 @@ let conflict_handler config : Mempool.conflict_handler =
   else if Operation.compare existing_operation new_operation < 0 then `Replace
   else `Keep
 
+let find_manager {shell = _; protocol_data = Operation_data {contents; _}} =
+  match contents with
+  | Single (Manager_operation {source; _}) -> Some source
+  | Cons (Manager_operation {source; _}, _) -> Some source
+  | Single
+      ( Preendorsement _ | Endorsement _ | Dal_attestation _ | Proposals _
+      | Ballot _ | Seed_nonce_revelation _ | Vdf_revelation _
+      | Double_baking_evidence _ | Double_preendorsement_evidence _
+      | Double_endorsement_evidence _ | Activate_account _ | Drain_delegate _
+      | Failing_noop _ ) ->
+      None
+
 let fee_needed_to_overtake ~op_to_overtake ~candidate_op =
   if is_manager_operation candidate_op && is_manager_operation op_to_overtake
   then
diff --git a/src/proto_016_PtMumbai/lib_plugin/mempool.mli b/src/proto_016_PtMumbai/lib_plugin/mempool.mli
index 4cafa6a597c0c8bab929820a8de29e9b7beac7d6..d7fe3212cb3775075a204d430a9da40138500bc0 100644
--- a/src/proto_016_PtMumbai/lib_plugin/mempool.mli
+++ b/src/proto_016_PtMumbai/lib_plugin/mempool.mli
@@ -103,6 +103,11 @@ val pre_filter :
     able to call {!Protocol.Alpha_context.Operation.compare}). *)
 val conflict_handler : config -> Protocol.Mempool.conflict_handler
 
+(** If the operation is a manager operation, return its source,
+    otherwise return [None]. *)
+val find_manager :
+  Protocol.Alpha_context.packed_operation -> Signature.Public_key_hash.t option
+
 (** Compute the minimal fee (expressed in mutez) that [candidate_op] would
     need to have in order to be strictly greater than [op_to_overtake]
     according to {!Protocol.Alpha_context.Operation.compare}, when both
diff --git a/src/proto_017_PtNairob/lib_plugin/mempool.ml b/src/proto_017_PtNairob/lib_plugin/mempool.ml
index 1bd7893fcbcf415b5fa5892821533aa704656fcf..2fe3a73d26ed07258f583e901a267aaf76c4b78f 100644
--- a/src/proto_017_PtNairob/lib_plugin/mempool.ml
+++ b/src/proto_017_PtNairob/lib_plugin/mempool.ml
@@ -616,6 +616,18 @@ let conflict_handler config : Mempool.conflict_handler =
   else if Operation.compare existing_operation new_operation < 0 then `Replace
   else `Keep
 
+let find_manager {shell = _; protocol_data = Operation_data {contents; _}} =
+  match contents with
+  | Single (Manager_operation {source; _}) -> Some source
+  | Cons (Manager_operation {source; _}, _) -> Some source
+  | Single
+      ( Preendorsement _ | Endorsement _ | Dal_attestation _ | Proposals _
+      | Ballot _ | Seed_nonce_revelation _ | Vdf_revelation _
+      | Double_baking_evidence _ | Double_preendorsement_evidence _
+      | Double_endorsement_evidence _ | Activate_account _ | Drain_delegate _
+      | Failing_noop _ ) ->
+      None
+
 let fee_needed_to_overtake ~op_to_overtake ~candidate_op =
   if is_manager_operation candidate_op && is_manager_operation op_to_overtake
   then
diff --git a/src/proto_017_PtNairob/lib_plugin/mempool.mli b/src/proto_017_PtNairob/lib_plugin/mempool.mli
index 4cafa6a597c0c8bab929820a8de29e9b7beac7d6..d7fe3212cb3775075a204d430a9da40138500bc0 100644
--- a/src/proto_017_PtNairob/lib_plugin/mempool.mli
+++ b/src/proto_017_PtNairob/lib_plugin/mempool.mli
@@ -103,6 +103,11 @@ val pre_filter :
     able to call {!Protocol.Alpha_context.Operation.compare}). *)
 val conflict_handler : config -> Protocol.Mempool.conflict_handler
 
+(** If the operation is a manager operation, return its source,
+    otherwise return [None]. *)
+val find_manager :
+  Protocol.Alpha_context.packed_operation -> Signature.Public_key_hash.t option
+
 (** Compute the minimal fee (expressed in mutez) that [candidate_op] would
     need to have in order to be strictly greater than [op_to_overtake]
     according to {!Protocol.Alpha_context.Operation.compare}, when both
diff --git a/src/proto_alpha/lib_plugin/mempool.ml b/src/proto_alpha/lib_plugin/mempool.ml
index be6587427d3b93ad1c1748338a1c113c5f2b7fe7..622bf9b7f1a44d8aab749687e0f4b746ed229e9d 100644
--- a/src/proto_alpha/lib_plugin/mempool.ml
+++ b/src/proto_alpha/lib_plugin/mempool.ml
@@ -618,6 +618,18 @@ let conflict_handler config : Mempool.conflict_handler =
   else if Operation.compare existing_operation new_operation < 0 then `Replace
   else `Keep
 
+let find_manager {shell = _; protocol_data = Operation_data {contents; _}} =
+  match contents with
+  | Single (Manager_operation {source; _}) -> Some source
+  | Cons (Manager_operation {source; _}, _) -> Some source
+  | Single
+      ( Preendorsement _ | Endorsement _ | Dal_attestation _ | Proposals _
+      | Ballot _ | Seed_nonce_revelation _ | Vdf_revelation _
+      | Double_baking_evidence _ | Double_preendorsement_evidence _
+      | Double_endorsement_evidence _ | Activate_account _ | Drain_delegate _
+      | Failing_noop _ ) ->
+      None
+
 let fee_needed_to_overtake ~op_to_overtake ~candidate_op =
   if is_manager_operation candidate_op && is_manager_operation op_to_overtake
   then
diff --git a/src/proto_alpha/lib_plugin/mempool.mli b/src/proto_alpha/lib_plugin/mempool.mli
index 4cafa6a597c0c8bab929820a8de29e9b7beac7d6..d7fe3212cb3775075a204d430a9da40138500bc0 100644
--- a/src/proto_alpha/lib_plugin/mempool.mli
+++ b/src/proto_alpha/lib_plugin/mempool.mli
@@ -103,6 +103,11 @@ val pre_filter :
     able to call {!Protocol.Alpha_context.Operation.compare}). *)
 val conflict_handler : config -> Protocol.Mempool.conflict_handler
 
+(** If the operation is a manager operation, return its source,
+    otherwise return [None]. *)
+val find_manager :
+  Protocol.Alpha_context.packed_operation -> Signature.Public_key_hash.t option
+
 (** Compute the minimal fee (expressed in mutez) that [candidate_op] would
     need to have in order to be strictly greater than [op_to_overtake]
     according to {!Protocol.Alpha_context.Operation.compare}, when both