diff --git a/app/serializers/procedure_serializer.rb b/app/serializers/procedure_serializer.rb
index 674d8ab91..d219ee4b6 100644
--- a/app/serializers/procedure_serializer.rb
+++ b/app/serializers/procedure_serializer.rb
@@ -16,7 +16,7 @@ class ProcedureSerializer < ActiveModel::Serializer
   has_one :geographic_information, serializer: ModuleApiCartoSerializer
   has_many :types_de_champ, serializer: TypeDeChampSerializer
   has_many :types_de_champ_private, serializer: TypeDeChampSerializer
-  has_many :types_de_piece_justificative, serializer: TypeDePieceJustificativeSerializer
+  has_many :types_de_piece_justificative
 
   def archived_at
     object.archived_at&.in_time_zone('UTC')
@@ -43,4 +43,9 @@ class ProcedureSerializer < ActiveModel::Serializer
       ModuleAPICarto.new(procedure: object)
     end
   end
+
+  def types_de_piece_justificative
+    ActiveModelSerializers::SerializableResource.new(object.types_de_piece_justificative).serializable_hash +
+      PiecesJustificativesService.serialize_types_de_champ_as_type_pj(object)
+  end
 end
diff --git a/app/services/pieces_justificatives_service.rb b/app/services/pieces_justificatives_service.rb
index 8a199a011..d0bc69815 100644
--- a/app/services/pieces_justificatives_service.rb
+++ b/app/services/pieces_justificatives_service.rb
@@ -67,4 +67,21 @@ class PiecesJustificativesService
       []
     end
   end
+
+  def self.serialize_types_de_champ_as_type_pj(procedure)
+    tdcs = procedure.types_de_champ.select { |type_champ| type_champ.old_pj.present? }
+    tdcs.map.with_index do |type_champ, order_place|
+      description = type_champ.description
+      if /^(?<original_description>.*?)(?:[\r\n]+)Récupérer le formulaire vierge pour mon dossier : (?<lien_demarche>http.*)$/m =~ description
+        description = original_description
+      end
+      {
+        id: type_champ.old_pj[:stable_id],
+        libelle: type_champ.libelle,
+        description: description,
+        order_place: order_place,
+        lien_demarche: lien_demarche
+      }
+    end
+  end
 end
diff --git a/spec/serializers/procedure_serializer_spec.rb b/spec/serializers/procedure_serializer_spec.rb
index 487866665..fa5bd006b 100644
--- a/spec/serializers/procedure_serializer_spec.rb
+++ b/spec/serializers/procedure_serializer_spec.rb
@@ -8,4 +8,38 @@ describe ProcedureSerializer do
       is_expected.to include(state: "publiee")
     }
   end
+
+  context 'when a type PJ was cloned to a type champ PJ' do
+    let(:original_procedure) do
+      p = create(:procedure, :published)
+      p.types_de_piece_justificative.create(
+        libelle: "Vidéo de votre demande de subvention",
+        description: "Pour optimiser vos chances, soignez la chorégraphie et privilégiez le chant polyphonique",
+        lien_demarche: "https://www.dance-academy.gouv.fr",
+        order_place: 0
+      )
+      p
+    end
+
+    let(:procedure) { original_procedure.clone(original_procedure.administrateur, false) }
+
+    let(:type_pj) { original_procedure.types_de_piece_justificative.first }
+    let(:migrated_type_champ) { procedure.types_de_champ.find_by(libelle: type_pj.libelle) }
+
+    subject { ProcedureSerializer.new(procedure).serializable_hash }
+
+    it "is exposed as a legacy type PJ" do
+      is_expected.to include(
+        types_de_piece_justificative: [
+          {
+            "id" => type_pj.id,
+            "libelle" => type_pj.libelle,
+            "description" => type_pj.description,
+            "lien_demarche" => type_pj.lien_demarche,
+            "order_place" => type_pj.order_place
+          }
+        ]
+      )
+    end
+  end
 end