diff --git a/app/controllers/api/public/v1/base_controller.rb b/app/controllers/api/public/v1/base_controller.rb
new file mode 100644
index 000000000..3aabeef32
--- /dev/null
+++ b/app/controllers/api/public/v1/base_controller.rb
@@ -0,0 +1,29 @@
+class API::Public::V1::BaseController < APIController
+  skip_forgery_protection
+
+  before_action :check_content_type_is_json
+
+  protected
+
+  def render_missing_param(param_name)
+    render_error("#{param_name} is missing", :bad_request)
+  end
+
+  def render_bad_request(error_message)
+    render_error(error_message, :bad_request)
+  end
+
+  def render_not_found(resource_name, resource_id)
+    render_error("#{resource_name} #{resource_id} is not found", :not_found)
+  end
+
+  private
+
+  def check_content_type_is_json
+    render_error("Content-Type should be json", :bad_request) unless request.headers['Content-Type'] == 'application/json'
+  end
+
+  def render_error(message, status)
+    render json: { error: message }, status: status
+  end
+end
diff --git a/app/controllers/api/public/v1/dossiers_controller.rb b/app/controllers/api/public/v1/dossiers_controller.rb
new file mode 100644
index 000000000..cffe7aa66
--- /dev/null
+++ b/app/controllers/api/public/v1/dossiers_controller.rb
@@ -0,0 +1,26 @@
+class API::Public::V1::DossiersController < API::Public::V1::BaseController
+  before_action :retrieve_procedure
+
+  def create
+    dossier = Dossier.new(
+      revision: @procedure.active_revision,
+      groupe_instructeur: @procedure.defaut_groupe_instructeur_for_new_dossier,
+      state: Dossier.states.fetch(:brouillon),
+      prefilled: true
+    )
+    dossier.build_default_individual
+    if dossier.save
+      dossier.prefill!(PrefillParams.new(dossier, params.to_unsafe_h).to_a)
+      render json: { dossier_url: commencer_url(@procedure.path, prefill_token: dossier.prefill_token) }, status: :created
+    else
+      render_bad_request(dossier.errors.full_messages.to_sentence)
+    end
+  end
+
+  private
+
+  def retrieve_procedure
+    @procedure = Procedure.publiees_ou_brouillons.find_by(id: params[:id])
+    render_not_found("procedure", params[:id]) if @procedure.blank?
+  end
+end
diff --git a/app/controllers/concerns/procedure_context_concern.rb b/app/controllers/concerns/procedure_context_concern.rb
index d2d7b5a2c..670df54c9 100644
--- a/app/controllers/concerns/procedure_context_concern.rb
+++ b/app/controllers/concerns/procedure_context_concern.rb
@@ -5,12 +5,14 @@ module ProcedureContextConcern
   include Devise::StoreLocationExtension
 
   def restore_procedure_context
-    if has_stored_procedure_path?
-      @procedure = find_procedure_in_context
+    return unless has_stored_procedure_path?
 
-      if @procedure.blank?
-        invalid_procedure_context
-      end
+    @procedure = find_procedure_in_context
+
+    if @procedure.blank?
+      invalid_procedure_context
+    else
+      @prefill_token = find_prefill_token_in_context
     end
   end
 
@@ -33,6 +35,11 @@ module ProcedureContextConcern
     end
   end
 
+  def find_prefill_token_in_context
+    uri = URI(get_stored_location_for(:user))
+    CGI.parse(uri.query).dig("prefill_token")&.first if uri.query
+  end
+
   def invalid_procedure_context
     clear_stored_location_for(:user)
     flash.alert = t('errors.messages.procedure_not_found')
diff --git a/app/controllers/users/commencer_controller.rb b/app/controllers/users/commencer_controller.rb
index c336738da..c416c98f8 100644
--- a/app/controllers/users/commencer_controller.rb
+++ b/app/controllers/users/commencer_controller.rb
@@ -4,6 +4,10 @@ module Users
 
     layout 'procedure_context'
 
+    before_action :retrieve_prefilled_dossier,        if: -> { params[:prefill_token].present? },                only: :commencer
+    before_action :set_prefilled_dossier_ownership,   if: -> { user_signed_in? && @prefilled_dossier&.orphan? }, only: :commencer
+    before_action :check_prefilled_dossier_ownership, if: -> { user_signed_in? && @prefilled_dossier },          only: :commencer
+
     def commencer
       @procedure = retrieve_procedure
       return procedure_not_found if @procedure.blank? || @procedure.brouillon?
@@ -74,6 +78,21 @@ module Users
       Procedure.publiees.or(Procedure.brouillons).or(Procedure.closes).find_by(path: params[:path])
     end
 
+    def retrieve_prefilled_dossier
+      @prefilled_dossier = Dossier.state_brouillon.prefilled.find_by!(prefill_token: params[:prefill_token])
+    end
+
+    # The prefilled dossier is not owned yet, and the user is signed in: they become the new owner
+    def set_prefilled_dossier_ownership
+      @prefilled_dossier.update!(user: current_user)
+      DossierMailer.with(dossier: @prefilled_dossier).notify_new_draft.deliver_later
+    end
+
+    # The prefilled dossier is owned by another user: raise an exception
+    def check_prefilled_dossier_ownership
+      raise ActiveRecord::RecordNotFound unless @prefilled_dossier.owned_by?(current_user)
+    end
+
     def procedure_not_found
       procedure = Procedure.find_by(path: params[:path])
 
@@ -92,7 +111,7 @@ module Users
     end
 
     def store_user_location!(procedure)
-      store_location_for(:user, helpers.procedure_lien(procedure))
+      store_location_for(:user, helpers.procedure_lien(procedure, prefill_token: params[:prefill_token]))
     end
 
     def generate_empty_pdf(revision)
diff --git a/app/controllers/users/confirmations_controller.rb b/app/controllers/users/confirmations_controller.rb
index ea3a1c37b..257456af0 100644
--- a/app/controllers/users/confirmations_controller.rb
+++ b/app/controllers/users/confirmations_controller.rb
@@ -45,7 +45,7 @@ class Users::ConfirmationsController < Devise::ConfirmationsController
     end
 
     if procedure_from_params
-      commencer_path(path: procedure_from_params.path)
+      commencer_path(path: procedure_from_params.path, prefill_token: params[:prefill_token])
     elsif signed_in?
       # Will try to use `stored_location_for` to find a path
       after_sign_in_path_for(resource_name)
diff --git a/app/controllers/users/registrations_controller.rb b/app/controllers/users/registrations_controller.rb
index 557050554..9136649cd 100644
--- a/app/controllers/users/registrations_controller.rb
+++ b/app/controllers/users/registrations_controller.rb
@@ -26,6 +26,7 @@ class Users::RegistrationsController < Devise::RegistrationsController
     # all Devise code.
     # So instead we use a per-request global variable.
     CurrentConfirmation.procedure_after_confirmation = @procedure
+    CurrentConfirmation.prefill_token = @prefill_token
 
     # Handle existing user trying to sign up again
     existing_user = User.find_by(email: params[:user][:email])
diff --git a/app/helpers/procedure_helper.rb b/app/helpers/procedure_helper.rb
index 7152824ba..23af7da97 100644
--- a/app/helpers/procedure_helper.rb
+++ b/app/helpers/procedure_helper.rb
@@ -1,9 +1,9 @@
 module ProcedureHelper
-  def procedure_lien(procedure)
+  def procedure_lien(procedure, prefill_token: nil)
     if procedure.brouillon?
-      commencer_test_url(path: procedure.path)
+      commencer_test_url(path: procedure.path, prefill_token: prefill_token)
     else
-      commencer_url(path: procedure.path)
+      commencer_url(path: procedure.path, prefill_token: prefill_token)
     end
   end
 
diff --git a/app/mailers/devise_user_mailer.rb b/app/mailers/devise_user_mailer.rb
index bc548c166..964fa2c5e 100644
--- a/app/mailers/devise_user_mailer.rb
+++ b/app/mailers/devise_user_mailer.rb
@@ -23,6 +23,7 @@ class DeviseUserMailer < Devise::Mailer
   def confirmation_instructions(record, token, opts = {})
     opts[:from] = NO_REPLY_EMAIL
     @procedure = opts[:procedure_after_confirmation] || nil
+    @prefill_token = opts[:prefill_token]
     super
   end
 end
diff --git a/app/models/concerns/dossier_prefillable_concern.rb b/app/models/concerns/dossier_prefillable_concern.rb
index ce88bc01b..35cf970ed 100644
--- a/app/models/concerns/dossier_prefillable_concern.rb
+++ b/app/models/concerns/dossier_prefillable_concern.rb
@@ -3,10 +3,11 @@
 module DossierPrefillableConcern
   extend ActiveSupport::Concern
 
-  def prefill!(champs_attributes)
-    return if champs_attributes.empty?
+  def prefill!(champs_public_attributes)
+    attr = { prefilled: true }
+    attr[:champs_public_attributes] = champs_public_attributes.map { |h| h.merge(prefilled: true) } if champs_public_attributes.any?
 
-    assign_attributes(champs_attributes: champs_attributes.map { |h| h.merge(prefilled: true) })
+    assign_attributes(attr)
     save(validate: false)
   end
 end
diff --git a/app/models/current_confirmation.rb b/app/models/current_confirmation.rb
index c25314d7b..ce9853ee2 100644
--- a/app/models/current_confirmation.rb
+++ b/app/models/current_confirmation.rb
@@ -1,3 +1,4 @@
 class CurrentConfirmation < ActiveSupport::CurrentAttributes
   attribute :procedure_after_confirmation
+  attribute :prefill_token
 end
diff --git a/app/models/dossier.rb b/app/models/dossier.rb
index d61596475..fa490d13e 100644
--- a/app/models/dossier.rb
+++ b/app/models/dossier.rb
@@ -28,6 +28,8 @@
 #  last_champ_updated_at                              :datetime
 #  last_commentaire_updated_at                        :datetime
 #  motivation                                         :text
+#  prefill_token                                      :string
+#  prefilled                                          :boolean
 #  private_search_terms                               :text
 #  processed_at                                       :datetime
 #  search_terms                                       :text
@@ -70,6 +72,8 @@ class Dossier < ApplicationRecord
   DAYS_AFTER_EXPIRATION = 5
   INTERVAL_EXPIRATION = "#{MONTHS_AFTER_EXPIRATION} month #{DAYS_AFTER_EXPIRATION} days"
 
+  has_secure_token :prefill_token
+
   has_one :etablissement, dependent: :destroy
   has_one :individual, validate: false, dependent: :destroy
   has_one :attestation, dependent: :destroy
@@ -218,11 +222,12 @@ class Dossier < ApplicationRecord
   scope :state_termine,                        -> { where(state: TERMINE) }
   scope :state_not_termine,                    -> { where.not(state: TERMINE) }
 
-  scope :archived,      -> { where(archived: true) }
-  scope :not_archived,  -> { where(archived: false) }
-  scope :hidden_by_user, -> { where.not(hidden_by_user_at: nil) }
-  scope :hidden_by_administration, -> { where.not(hidden_by_administration_at: nil) }
-  scope :visible_by_user, -> { where(for_procedure_preview: false).or(where(for_procedure_preview: nil)).where(hidden_by_user_at: nil) }
+  scope :archived,                  -> { where(archived: true) }
+  scope :not_archived,              -> { where(archived: false) }
+  scope :prefilled,                 -> { where(prefilled: true) }
+  scope :hidden_by_user,            -> { where.not(hidden_by_user_at: nil) }
+  scope :hidden_by_administration,  -> { where.not(hidden_by_administration_at: nil) }
+  scope :visible_by_user,           -> { where(for_procedure_preview: false).or(where(for_procedure_preview: nil)).where(hidden_by_user_at: nil) }
   scope :visible_by_administration, -> {
     state_not_brouillon
       .where(hidden_by_administration_at: nil)
@@ -435,7 +440,7 @@ class Dossier < ApplicationRecord
 
   after_save :send_web_hook
 
-  validates :user, presence: true, if: -> { deleted_user_email_never_send.nil? }
+  validates :user, presence: true, if: -> { deleted_user_email_never_send.nil? }, unless: -> { prefilled }
   validates :individual, presence: true, if: -> { revision.procedure.for_individual? }
   validates :groupe_instructeur, presence: true, if: -> { !brouillon? }
 
@@ -718,6 +723,17 @@ class Dossier < ApplicationRecord
     end
   end
 
+  def orphan?
+    prefilled? && user.nil?
+  end
+
+  def owned_by?(a_user)
+    return false if a_user.nil?
+    return false if orphan?
+
+    user == a_user
+  end
+
   def log_operations?
     !procedure.brouillon? && !brouillon?
   end
diff --git a/app/models/procedure.rb b/app/models/procedure.rb
index 34ea5f432..e2d783a92 100644
--- a/app/models/procedure.rb
+++ b/app/models/procedure.rb
@@ -206,7 +206,7 @@ class Procedure < ApplicationRecord
 
   scope :brouillons,             -> { where(aasm_state: :brouillon) }
   scope :publiees,               -> { where(aasm_state: :publiee) }
-  scope :publiees_ou_brouillons, -> { publiees.or(brouillons) }
+  scope :publiees_ou_brouillons, -> { where(aasm_state: [:publiee, :brouillon]) }
   scope :closes,                 -> { where(aasm_state: [:close, :depubliee]) }
   scope :opendata,               -> { where(opendata: true) }
   scope :publiees_ou_closes,     -> { where(aasm_state: [:publiee, :close, :depubliee]) }
diff --git a/app/models/user.rb b/app/models/user.rb
index 5d6589829..0163890b7 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -80,6 +80,7 @@ class User < ApplicationRecord
 
     # Make our procedure_after_confirmation available to the Mailer
     opts[:procedure_after_confirmation] = CurrentConfirmation.procedure_after_confirmation
+    opts[:prefill_token] = CurrentConfirmation.prefill_token
 
     send_devise_notification(:confirmation_instructions, @raw_confirmation_token, opts)
   end
diff --git a/app/views/commencer/show.html.haml b/app/views/commencer/show.html.haml
index 0b755b554..553f1198e 100644
--- a/app/views/commencer/show.html.haml
+++ b/app/views/commencer/show.html.haml
@@ -3,12 +3,12 @@
 .commencer.form
   - if !user_signed_in?
     %h2.huge-title= t('views.commencer.show.start_procedure')
-    = render partial: 'shared/france_connect_login', locals: { url: commencer_france_connect_path(path: @procedure.path) }
-    = link_to commencer_sign_up_path(path: @procedure.path), class: 'fr-btn fr-btn--lg fr-my-2w' do
+    = render partial: 'shared/france_connect_login', locals: { url: commencer_france_connect_path(path: @procedure.path, prefill_token: @prefilled_dossier&.prefill_token) }
+    = link_to commencer_sign_up_path(path: @procedure.path, prefill_token: @prefilled_dossier&.prefill_token), class: 'fr-btn fr-btn--lg fr-my-2w' do
       = t('views.shared.account.create')
       %span.optional-on-small-screens.fr-ml-1v
         #{APPLICATION_NAME}
-    = link_to t('views.shared.account.already_user'), commencer_sign_in_path(path: @procedure.path), class: 'fr-btn fr-btn--secondary fr-btn--lg fr-my-2w'
+    = link_to t('views.shared.account.already_user'), commencer_sign_in_path(path: @procedure.path, prefill_token: @prefilled_dossier&.prefill_token), class: 'fr-btn fr-btn--secondary fr-btn--lg fr-my-2w'
 
   - else
     - revision = @revision.draft? ? @revision : @procedure.revisions.where.not(id: @procedure.draft_revision_id)
@@ -19,6 +19,13 @@
     - if dossiers.empty?
       = link_to t('views.commencer.show.start_procedure'), url_for_new_dossier(@revision), class: 'fr-btn fr-btn--lg fr-my-2w'
 
+    - elsif @prefilled_dossier
+      %h2.huge-title= t('views.commencer.show.prefilled_draft')
+      %p
+        = t('views.commencer.show.prefilled_draft_detail_html', time_ago: time_ago_in_words(@prefilled_dossier.created_at), procedure: @prefilled_dossier.procedure.libelle)
+      = link_to t('views.commencer.show.continue_file'), brouillon_dossier_path(@prefilled_dossier), class: 'fr-btn fr-btn--lg fr-my-2w'
+      = link_to t('views.commencer.show.start_new_file'), url_for_new_dossier(@revision), class: 'fr-btn fr-btn--lg fr-btn--secondary fr-my-2w'
+
     - elsif drafts.size == 1 && not_drafts.empty?
       - dossier = drafts.first
       %h2.huge-title= t('views.commencer.show.already_draft')
diff --git a/app/views/devise_mailer/confirmation_instructions.html.haml b/app/views/devise_mailer/confirmation_instructions.html.haml
index cab00c327..ba4904207 100644
--- a/app/views/devise_mailer/confirmation_instructions.html.haml
+++ b/app/views/devise_mailer/confirmation_instructions.html.haml
@@ -6,7 +6,7 @@
 
   %p
     Pour activer votre compte sur #{APPLICATION_NAME}, veuillez cliquer sur le lien suivant :
-    - link = confirmation_url(@user, confirmation_token: @token, procedure_id: @procedure&.id)
+    - link = confirmation_url(@user, confirmation_token: @token, procedure_id: @procedure&.id, prefill_token: @prefill_token)
     = link_to(link, link)
 
 - else
diff --git a/config/locales/en.yml b/config/locales/en.yml
index 20be22169..8f5a48112 100644
--- a/config/locales/en.yml
+++ b/config/locales/en.yml
@@ -92,6 +92,8 @@ en:
         start_procedure: Start the procedure
         existing_dossiers: You already have files for this procedure
         show_dossiers: View my current files
+        prefilled_draft: "You have a prefilled file"
+        prefilled_draft_detail_html: "You prefilled a file for the \"%{procedure}\" procedure <strong>%{time_ago} ago</strong>"
         already_draft: "You already started to fill a file"
         already_draft_detail_html: "You started to fill a file for the \"%{procedure}\" procedure <strong>%{time_ago} ago</strong>"
         already_not_draft: "You already submitted a file"
diff --git a/config/locales/fr.yml b/config/locales/fr.yml
index 8367c0ca5..f73bd0001 100644
--- a/config/locales/fr.yml
+++ b/config/locales/fr.yml
@@ -82,6 +82,8 @@ fr:
         start_procedure: Commencer la démarche
         existing_dossiers: Vous avez déjà des dossiers pour cette démarche
         show_dossiers: Voir mes dossiers en cours
+        prefilled_draft: "Vous avez un dossier prérempli"
+        prefilled_draft_detail_html: "Il y a <strong>%{time_ago}</strong>, vous avez prérempli un dossier sur la démarche « %{procedure} »."
         already_draft: "Vous avez déjà commencé à remplir un dossier"
         already_draft_detail_html: "Il y a <strong>%{time_ago}</strong>, vous avez commencé à remplir un dossier sur la démarche « %{procedure} »."
         already_not_draft: "Vous avez déjà déposé un dossier"
diff --git a/config/routes.rb b/config/routes.rb
index d7a66e23f..4d165b3e7 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -263,7 +263,11 @@ Rails.application.routes.draw do
 
     namespace :public do
       namespace :v1 do
-        resources :dossiers, only: :create
+        resources :demarches, only: [] do
+          member do
+            resources :dossiers, only: :create
+          end
+        end
       end
     end
   end
diff --git a/db/migrate/20221213084333_add_prefill_fields_to_dossiers.rb b/db/migrate/20221213084333_add_prefill_fields_to_dossiers.rb
new file mode 100644
index 000000000..28c34a296
--- /dev/null
+++ b/db/migrate/20221213084333_add_prefill_fields_to_dossiers.rb
@@ -0,0 +1,6 @@
+class AddPrefillFieldsToDossiers < ActiveRecord::Migration[6.1]
+  def change
+    add_column :dossiers, :prefill_token, :string
+    add_column :dossiers, :prefilled, :boolean
+  end
+end
diff --git a/db/migrate/20221213084442_add_prefill_token_index_to_dossiers.rb b/db/migrate/20221213084442_add_prefill_token_index_to_dossiers.rb
new file mode 100644
index 000000000..349224504
--- /dev/null
+++ b/db/migrate/20221213084442_add_prefill_token_index_to_dossiers.rb
@@ -0,0 +1,7 @@
+class AddPrefillTokenIndexToDossiers < ActiveRecord::Migration[6.1]
+  disable_ddl_transaction!
+
+  def change
+    add_index :dossiers, :prefill_token, unique: true, algorithm: :concurrently
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
index 309bb650c..313080e07 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 2022_12_05_144624) do
+ActiveRecord::Schema.define(version: 2022_12_13_084442) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "pgcrypto"
@@ -298,13 +298,13 @@ ActiveRecord::Schema.define(version: 2022_12_05_144624) do
     t.boolean "automatic_operation", default: false, null: false
     t.bigint "bill_signature_id"
     t.datetime "created_at", null: false
+    t.jsonb "data"
     t.text "digest"
     t.bigint "dossier_id"
     t.datetime "executed_at"
     t.datetime "keep_until"
     t.string "operation", null: false
     t.datetime "updated_at", null: false
-    t.jsonb "data"
     t.index ["bill_signature_id"], name: "index_dossier_operation_logs_on_bill_signature_id"
     t.index ["dossier_id"], name: "index_dossier_operation_logs_on_dossier_id"
     t.index ["keep_until"], name: "index_dossier_operation_logs_on_keep_until"
@@ -363,6 +363,8 @@ ActiveRecord::Schema.define(version: 2022_12_05_144624) do
     t.datetime "last_commentaire_updated_at"
     t.text "motivation"
     t.bigint "parent_dossier_id"
+    t.string "prefill_token"
+    t.boolean "prefilled"
     t.string "private_search_terms"
     t.datetime "processed_at"
     t.bigint "revision_id"
@@ -376,6 +378,7 @@ ActiveRecord::Schema.define(version: 2022_12_05_144624) do
     t.index ["dossier_transfer_id"], name: "index_dossiers_on_dossier_transfer_id"
     t.index ["groupe_instructeur_id"], name: "index_dossiers_on_groupe_instructeur_id"
     t.index ["hidden_at"], name: "index_dossiers_on_hidden_at"
+    t.index ["prefill_token"], name: "index_dossiers_on_prefill_token", unique: true
     t.index ["revision_id"], name: "index_dossiers_on_revision_id"
     t.index ["state"], name: "index_dossiers_on_state"
     t.index ["user_id"], name: "index_dossiers_on_user_id"
@@ -807,6 +810,7 @@ ActiveRecord::Schema.define(version: 2022_12_05_144624) do
     t.datetime "reset_password_sent_at"
     t.string "reset_password_token"
     t.integer "sign_in_count", default: 0, null: false
+    t.boolean "team_account", default: false
     t.string "unlock_token"
     t.datetime "updated_at"
     t.index ["email"], name: "index_super_admins_on_email", unique: true
@@ -885,7 +889,6 @@ ActiveRecord::Schema.define(version: 2022_12_05_144624) do
     t.string "reset_password_token"
     t.integer "sign_in_count", default: 0, null: false
     t.string "siret"
-    t.boolean "team_account", default: false
     t.text "unconfirmed_email"
     t.string "unlock_token"
     t.datetime "updated_at"
diff --git a/spec/controllers/api/public/v1/dossiers_controller_spec.rb b/spec/controllers/api/public/v1/dossiers_controller_spec.rb
new file mode 100644
index 000000000..e4cc80de9
--- /dev/null
+++ b/spec/controllers/api/public/v1/dossiers_controller_spec.rb
@@ -0,0 +1,135 @@
+RSpec.describe API::Public::V1::DossiersController, type: :controller do
+  include Rails.application.routes.url_helpers
+
+  describe '#create' do
+    # Request prototype:
+    # curl --request POST 'http://localhost:3000/api/public/v1/demarches/2/dossiers' \
+    # --header 'Content-Type: application/json' \
+    # --data '{"champ_Q2hhbXAtMjI=": "personne@fournisseur.fr"}'
+
+    context 'when the request content type is json' do
+      let(:params) { { id: procedure.id } }
+      subject(:create_request) do
+        request.headers["Content-Type"] = "application/json"
+        post :create, params: params
+      end
+
+      shared_examples 'the procedure is found' do
+        context 'when the dossier can be saved' do
+          it { expect(create_request).to have_http_status(:created) }
+
+          it { expect { create_request }.to change { Dossier.count }.by(1) }
+
+          it "marks the created dossier as prefilled" do
+            create_request
+            expect(Dossier.last.prefilled).to eq(true)
+          end
+
+          it "creates the dossier without a user" do
+            create_request
+            expect(Dossier.last.user).to eq(nil)
+          end
+
+          it "responds with the brouillon dossier path" do
+            create_request
+            expect(JSON.parse(response.body)["dossier_url"]).to eq(
+              "http://test.host#{commencer_path(procedure.path, prefill_token: Dossier.last.prefill_token)}"
+            )
+          end
+
+          context 'when prefill values are given' do
+            let!(:type_de_champ_1) { create(:type_de_champ_text, procedure: procedure) }
+            let(:value_1) { "any value" }
+
+            let!(:type_de_champ_2) { create(:type_de_champ_textarea, procedure: procedure) }
+            let(:value_2) { "another value" }
+
+            let(:params) {
+              {
+                id: procedure.id,
+                "champ_#{type_de_champ_1.to_typed_id}" => value_1,
+                "champ_#{type_de_champ_2.to_typed_id}" => value_2
+              }
+            }
+
+            it "prefills the dossier's champs with the given values" do
+              create_request
+
+              dossier = Dossier.last
+              expect(find_champ_by_stable_id(dossier, type_de_champ_1.stable_id).value).to eq(value_1)
+              expect(find_champ_by_stable_id(dossier, type_de_champ_2.stable_id).value).to eq(value_2)
+            end
+          end
+        end
+
+        context 'when the dossier can not be saved' do
+          before do
+            allow_any_instance_of(Dossier).to receive(:save).and_return(false)
+            allow_any_instance_of(Dossier).to receive(:errors).and_return(
+              ActiveModel::Errors.new(Dossier.new).tap { |e| e.add(:base, "something went wrong") }
+            )
+
+            create_request
+          end
+
+          it { expect(response).to have_http_status(:bad_request) }
+
+          it { expect(response).to have_failed_with("something went wrong") }
+        end
+      end
+
+      shared_examples 'the procedure is not found' do
+        before { create_request }
+
+        it { expect(response).to have_http_status(:not_found) }
+
+        it { expect(response).to have_failed_with("procedure #{procedure.id} is not found") }
+      end
+
+      context 'when the procedure is found' do
+        context 'when the procedure is publiee' do
+          it_behaves_like 'the procedure is found' do
+            let(:procedure) { create(:procedure, :published) }
+          end
+        end
+
+        context 'when the procedure is brouillon' do
+          it_behaves_like 'the procedure is found' do
+            let(:procedure) { create(:procedure, :draft) }
+          end
+        end
+
+        context 'when the procedure is not publiee and not brouillon' do
+          it_behaves_like 'the procedure is not found' do
+            let(:procedure) { create(:procedure, :closed) }
+          end
+        end
+      end
+
+      context 'when the procedure is not found' do
+        it_behaves_like 'the procedure is not found' do
+          let(:procedure) { double(Procedure, id: -1) }
+        end
+      end
+    end
+
+    context 'when the request content type is not json' do
+      subject(:create_request) do
+        request.headers["Content-Type"] = "application/xhtml+xml"
+        post :create, params: { id: 0 }
+      end
+
+      before { create_request }
+
+      it { expect(response).to have_http_status(:bad_request) }
+
+      it { expect(response).to have_failed_with("Content-Type should be json") }
+    end
+  end
+
+  private
+
+  def find_champ_by_stable_id(dossier, stable_id)
+    dossier.champs_public.joins(:type_de_champ).find_by(types_de_champ: { stable_id: stable_id })
+  end
+end
diff --git a/spec/controllers/concerns/procedure_context_concern_spec.rb b/spec/controllers/concerns/procedure_context_concern_spec.rb
index 9a3f81e25..10f6a185d 100644
--- a/spec/controllers/concerns/procedure_context_concern_spec.rb
+++ b/spec/controllers/concerns/procedure_context_concern_spec.rb
@@ -69,6 +69,19 @@ RSpec.describe ProcedureContextConcern, type: :controller do
           expect(subject.status).to eq 200
           expect(assigns(:procedure)).to eq test_procedure
         end
+
+        context 'when a prefill token has been stored' do
+          let(:dossier) { create :dossier, :prefilled, procedure: test_procedure }
+
+          before do
+            controller.store_location_for(:user, commencer_test_path(path: test_procedure.path, prefill_token: dossier.prefill_token))
+          end
+
+          it 'succeeds, and assigns the prefill token on the controller' do
+            expect(subject.status).to eq 200
+            expect(assigns(:prefill_token)).to eq dossier.prefill_token
+          end
+        end
       end
 
       context 'when the stored procedure is published' do
@@ -82,6 +95,19 @@ RSpec.describe ProcedureContextConcern, type: :controller do
           expect(subject.status).to eq 200
           expect(assigns(:procedure)).to eq published_procedure
         end
+
+        context 'when a prefill token has been stored' do
+          let(:dossier) { create :dossier, :prefilled, procedure: published_procedure }
+
+          before do
+            controller.store_location_for(:user, commencer_path(path: published_procedure.path, prefill_token: dossier.prefill_token))
+          end
+
+          it 'succeeds, and assigns the prefill token on the controller' do
+            expect(subject.status).to eq 200
+            expect(assigns(:prefill_token)).to eq dossier.prefill_token
+          end
+        end
       end
     end
   end
diff --git a/spec/controllers/users/commencer_controller_spec.rb b/spec/controllers/users/commencer_controller_spec.rb
index d64094521..f4370c526 100644
--- a/spec/controllers/users/commencer_controller_spec.rb
+++ b/spec/controllers/users/commencer_controller_spec.rb
@@ -72,6 +72,85 @@ describe Users::CommencerController, type: :controller do
         expect(subject).to redirect_to(commencer_path(path: replaced_by_procedure.path))
       end
     end
+
+    context 'when a dossier has been prefilled' do
+      let(:dossier) { create(:dossier, :brouillon, :prefilled, user: user) }
+      let(:path) { dossier.procedure.path }
+
+      subject { get :commencer, params: { path: path, prefill_token: dossier.prefill_token } }
+
+      shared_examples 'a prefilled brouillon dossier retriever' do
+        context 'when the dossier is a prefilled brouillon and the prefill token is present' do
+          it 'retrieves the dossier' do
+            subject
+            expect(assigns(:prefilled_dossier)).to eq(dossier)
+          end
+        end
+
+        context 'when the dossier is not prefilled' do
+          before do
+            dossier.prefilled = false
+            dossier.save(validate: false)
+          end
+
+          it { expect { subject }.to raise_error(ActiveRecord::RecordNotFound) }
+        end
+
+        context 'when the dossier is not a brouillon' do
+          before { dossier.en_construction! }
+
+          it { expect { subject }.to raise_error(ActiveRecord::RecordNotFound) }
+        end
+
+        context 'when the prefill token does not match any dossier' do
+          before { dossier.prefill_token = "totoro" }
+
+          it { expect { subject }.to raise_error(ActiveRecord::RecordNotFound) }
+        end
+      end
+
+      context 'when the user is unauthenticated' do
+        let(:user) { nil }
+
+        it_behaves_like 'a prefilled brouillon dossier retriever'
+      end
+
+      context 'when the user is authenticated' do
+        context 'when the dossier already has an owner' do
+          let(:user) { create(:user) }
+
+          context 'when the user is the dossier owner' do
+            before { sign_in user }
+
+            it_behaves_like 'a prefilled brouillon dossier retriever'
+          end
+
+          context 'when the user is not the dossier owner' do
+            before { sign_in create(:user) }
+
+            it { expect { subject }.to raise_error(ActiveRecord::RecordNotFound) }
+          end
+        end
+
+        context 'when the dossier does not have an owner yet' do
+          let(:user) { nil }
+          let(:newly_authenticated_user) { create(:user) }
+
+          before { sign_in newly_authenticated_user }
+
+          it { expect { subject }.to change { dossier.reload.user }.from(nil).to(newly_authenticated_user) }
+
+          it 'sends the notify_new_draft email' do
+            expect { perform_enqueued_jobs { subject } }.to change { ActionMailer::Base.deliveries.count }.by(1)
+
+            dossier = Dossier.last
+            mail = ActionMailer::Base.deliveries.last
+            expect(mail.subject).to eq("Retrouvez votre brouillon pour la démarche « #{dossier.procedure.libelle} »")
+            expect(mail.html_part.body).to include(dossier_path(dossier))
+          end
+        end
+      end
+    end
   end
 
   describe '#commencer_test' do
@@ -105,6 +184,13 @@ describe Users::CommencerController, type: :controller do
     end
   end
 
+  shared_examples 'a prefill token storage' do
+    it 'stores the prefill token' do
+      subject
+      expect(controller.stored_location_for(:user)).to include('prefill_token')
+    end
+  end
+
   describe '#sign_in' do
     context 'for a published procedure' do
       subject { get :sign_in, params: { path: published_procedure.path } }
@@ -115,6 +201,12 @@ describe Users::CommencerController, type: :controller do
       end
 
       it { expect(subject).to redirect_to(new_user_session_path) }
+
+      context 'when a prefill token is given' do
+        subject { get :sign_in, params: { path: published_procedure.path, prefill_token: 'prefill_token' } }
+
+        it_behaves_like 'a prefill token storage'
+      end
     end
 
     context 'for a draft procedure' do
@@ -126,6 +218,12 @@ describe Users::CommencerController, type: :controller do
       end
 
       it { expect(subject).to redirect_to(new_user_session_path) }
+
+      context 'when a prefill token is given' do
+        subject { get :sign_in, params: { path: draft_procedure.path, prefill_token: 'prefill_token' } }
+
+        it_behaves_like 'a prefill token storage'
+      end
     end
 
     context 'when the path doesn’t exist' do
@@ -147,6 +245,12 @@ describe Users::CommencerController, type: :controller do
       end
 
       it { expect(subject).to redirect_to(new_user_registration_path) }
+
+      context 'when a prefill token is given' do
+        subject { get :sign_up, params: { path: published_procedure.path, prefill_token: 'prefill_token' } }
+
+        it_behaves_like 'a prefill token storage'
+      end
     end
 
     context 'for a draft procedure' do
@@ -158,6 +262,12 @@ describe Users::CommencerController, type: :controller do
       end
 
       it { expect(subject).to redirect_to(new_user_registration_path) }
+
+      context 'when a prefill token is given' do
+        subject { get :sign_up, params: { path: draft_procedure.path, prefill_token: 'prefill_token' } }
+
+        it_behaves_like 'a prefill token storage'
+      end
     end
 
     context 'when the path doesn’t exist' do
@@ -179,6 +289,12 @@ describe Users::CommencerController, type: :controller do
       end
 
       it { expect(subject).to redirect_to(france_connect_particulier_path) }
+
+      context 'when a prefill token is given' do
+        subject { get :france_connect, params: { path: published_procedure.path, prefill_token: 'prefill_token' } }
+
+        it_behaves_like 'a prefill token storage'
+      end
     end
 
     context 'for a draft procedure' do
@@ -190,6 +306,12 @@ describe Users::CommencerController, type: :controller do
       end
 
       it { expect(subject).to redirect_to(france_connect_particulier_path) }
+
+      context 'when a prefill token is given' do
+        subject { get :france_connect, params: { path: draft_procedure.path, prefill_token: 'prefill_token' } }
+
+        it_behaves_like 'a prefill token storage'
+      end
     end
 
     context 'when the path doesn’t exist' do
diff --git a/spec/factories/dossier.rb b/spec/factories/dossier.rb
index 56a4d36d9..c766505cd 100644
--- a/spec/factories/dossier.rb
+++ b/spec/factories/dossier.rb
@@ -256,5 +256,9 @@ FactoryBot.define do
         dossier.save!
       end
     end
+
+    trait :prefilled do
+      prefilled { true }
+    end
   end
 end
diff --git a/spec/mailers/previews/devise_user_mailer_preview.rb b/spec/mailers/previews/devise_user_mailer_preview.rb
index e79fc17fc..1f0869098 100644
--- a/spec/mailers/previews/devise_user_mailer_preview.rb
+++ b/spec/mailers/previews/devise_user_mailer_preview.rb
@@ -8,6 +8,10 @@ class DeviseUserMailerPreview < ActionMailer::Preview
     DeviseUserMailer.confirmation_instructions(user, "faketoken", {})
   end
 
+  def confirmation_instructions___with_procedure_and_prefill_token
+    DeviseUserMailer.confirmation_instructions(user, "faketoken", procedure_after_confirmation: procedure, prefill_token: "prefill_token")
+  end
+
   def reset_password_instructions
     DeviseUserMailer.reset_password_instructions(user, "faketoken", {})
   end
diff --git a/spec/models/concern/dossier_prefillable_concern_spec.rb b/spec/models/concern/dossier_prefillable_concern_spec.rb
index e6c8e6bfa..58de07d7d 100644
--- a/spec/models/concern/dossier_prefillable_concern_spec.rb
+++ b/spec/models/concern/dossier_prefillable_concern_spec.rb
@@ -8,12 +8,19 @@ RSpec.describe DossierPrefillableConcern do
 
     subject(:fill) { dossier.prefill!(values); dossier.reload }
 
+    shared_examples 'a dossier marked as prefilled' do
+      it 'marks the dossier as prefilled' do
+        expect { fill }.to change { dossier.reload.prefilled }.from(nil).to(true)
+      end
+    end
+
     context 'when champs_public_attributes is empty' do
       let(:values) { [] }
 
-      it "does nothing" do
-        expect(dossier).not_to receive(:save)
-        fill
+      it_behaves_like 'a dossier marked as prefilled'
+
+      it "doesn't change champs_public" do
+        expect { fill }.not_to change { dossier.champs_public.to_a }
       end
     end
 
@@ -30,6 +37,8 @@ RSpec.describe DossierPrefillableConcern do
 
         let(:values) { [{ id: champ_id_1, value: value_1 }, { id: champ_id_2, value: value_2 }] }
 
+        it_behaves_like 'a dossier marked as prefilled'
+
         it "updates the champs with the new values and mark them as prefilled" do
           fill
 
@@ -48,6 +57,8 @@ RSpec.describe DossierPrefillableConcern do
 
         let(:values) { [{ id: champ_id, value: value }] }
 
+        it_behaves_like 'a dossier marked as prefilled'
+
         it "still updates the champ" do
           expect { fill }.to change { dossier.champs_public.first.value }.from(nil).to(value)
         end
diff --git a/spec/models/dossier_spec.rb b/spec/models/dossier_spec.rb
index 165870ec8..9b1f509df 100644
--- a/spec/models/dossier_spec.rb
+++ b/spec/models/dossier_spec.rb
@@ -25,6 +25,20 @@ describe Dossier do
     subject(:dossier) { create(:dossier, procedure: procedure) }
 
     it { is_expected.to validate_presence_of(:individual) }
+
+    it { is_expected.to validate_presence_of(:user) }
+
+    context 'when dossier has deleted_user_email_never_send' do
+      subject(:dossier) { create(:dossier, procedure: procedure, deleted_user_email_never_send: "seb@totoro.org") }
+
+      it { is_expected.not_to validate_presence_of(:user) }
+    end
+
+    context 'when dossier is prefilled' do
+      subject(:dossier) { create(:dossier, procedure: procedure, prefilled: true) }
+
+      it { is_expected.not_to validate_presence_of(:user) }
+    end
   end
 
   describe 'with_champs' do
@@ -1928,6 +1942,70 @@ describe Dossier do
     it { is_expected.to belong_to(:batch_operation).optional }
   end
 
+  describe '#orphan?' do
+    subject(:orphan) { dossier.orphan? }
+
+    context 'when the dossier is prefilled' do
+      context 'when the dossier has a user' do
+        let(:dossier) { build(:dossier, :prefilled) }
+
+        it { expect(orphan).to be_falsey }
+      end
+
+      context 'when the dossier does not have a user' do
+        let(:dossier) { build(:dossier, :prefilled, user: nil) }
+
+        it { expect(orphan).to be_truthy }
+      end
+    end
+
+    context 'when the dossier is not prefilled' do
+      context 'when the dossier has a user' do
+        let(:dossier) { build(:dossier) }
+
+        it { expect(orphan).to be_falsey }
+      end
+
+      context 'when the dossier does not have a user' do
+        let(:dossier) { build(:dossier, user: nil) }
+
+        it { expect(orphan).to be_falsey }
+      end
+    end
+  end
+
+  describe '#owned_by?' do
+    subject(:owned_by) { dossier.owned_by?(user) }
+
+    context 'when the dossier is orphan' do
+      let(:dossier) { build(:dossier, user: nil) }
+      let(:user) { build(:user) }
+
+      it { expect(owned_by).to be_falsey }
+    end
+
+    context 'when the given user is nil' do
+      let(:dossier) { build(:dossier) }
+      let(:user) { nil }
+
+      it { expect(owned_by).to be_falsey }
+    end
+
+    context 'when the dossier has a user and it is not the given user' do
+      let(:dossier) { build(:dossier) }
+      let(:user) { build(:user) }
+
+      it { expect(owned_by).to be_falsey }
+    end
+
+    context 'when the dossier has a user and it is the given user' do
+      let(:dossier) { build(:dossier, user: user) }
+      let(:user) { build(:user) }
+
+      it { expect(owned_by).to be_truthy }
+    end
+  end
+
   private
 
   def count_for_month(processed_by_month, month)
diff --git a/spec/support/public_api_matchers.rb b/spec/support/public_api_matchers.rb
new file mode 100644
index 000000000..bf856520c
--- /dev/null
+++ b/spec/support/public_api_matchers.rb
@@ -0,0 +1,5 @@
+RSpec::Matchers.define :have_failed_with do |expected|
+  match do |response|
+    JSON.parse(response.body).with_indifferent_access.dig(:error) == expected
+  end
+end
diff --git a/spec/support/shared_examples_for_prefilled_dossier.rb b/spec/support/shared_examples_for_prefilled_dossier.rb
new file mode 100644
index 000000000..f5a8faaf8
--- /dev/null
+++ b/spec/support/shared_examples_for_prefilled_dossier.rb
@@ -0,0 +1,22 @@
+shared_examples "the user has got a prefilled dossier, owned by themselves" do
+  scenario "the user has got a prefilled dossier, owned by themselves" do
+    siret = '41816609600051'
+    stub_request(:get, /https:\/\/entreprise.api.gouv.fr\/v2\/etablissements\/#{siret}/)
+      .to_return(status: 200, body: File.read('spec/fixtures/files/api_entreprise/etablissements.json'))
+
+    expect(dossier.user).to eq(user)
+
+    expect(page).to have_current_path siret_dossier_path(procedure.dossiers.last)
+    fill_in 'Numéro SIRET', with: siret
+    click_on 'Valider'
+
+    expect(page).to have_current_path(etablissement_dossier_path(dossier))
+    expect(page).to have_content('OCTO TECHNOLOGY')
+    click_on 'Continuer avec ces informations'
+
+    expect(page).to have_current_path(brouillon_dossier_path(dossier))
+    expect(page).to have_field(type_de_champ_text.libelle, with: text_value)
+    expect(page).to have_field(type_de_champ_phone.libelle, with: phone_value)
+    expect(page).to have_css('.field_with_errors', text: type_de_champ_phone.libelle)
+  end
+end
diff --git a/spec/system/users/dossier_prefill_get_spec.rb b/spec/system/users/dossier_prefill_get_spec.rb
new file mode 100644
index 000000000..d7b9eed35
--- /dev/null
+++ b/spec/system/users/dossier_prefill_get_spec.rb
@@ -0,0 +1,87 @@
+describe 'Prefilling a dossier (with a GET request):' do
+  let(:password) { 'my-s3cure-p4ssword' }
+
+  let(:procedure) { create(:procedure, :published, opendata: true) }
+  let(:dossier) { procedure.dossiers.last }
+
+  let(:type_de_champ_text) { create(:type_de_champ_text, procedure: procedure) }
+  let(:type_de_champ_phone) { create(:type_de_champ_phone, procedure: procedure) }
+  let(:text_value) { "My Neighbor Totoro is the best movie ever" }
+  let(:phone_value) { "invalid phone value" }
+
+  context 'when authenticated' do
+    it_behaves_like "the user has got a prefilled dossier, owned by themselves" do
+      let(:user) { create(:user, password: password) }
+
+      before do
+        visit "/users/sign_in"
+        sign_in_with user.email, password
+
+        visit commencer_path(
+          path: procedure.path,
+          "champ_#{type_de_champ_text.to_typed_id}" => text_value,
+          "champ_#{type_de_champ_phone.to_typed_id}" => phone_value
+        )
+
+        click_on "Commencer la démarche"
+      end
+    end
+  end
+
+  context 'when unauthenticated' do
+    before do
+      visit commencer_path(
+        path: procedure.path,
+        "champ_#{type_de_champ_text.to_typed_id}" => text_value,
+        "champ_#{type_de_champ_phone.to_typed_id}" => phone_value
+      )
+    end
+
+    context 'when the user signs in with email and password' do
+      it_behaves_like "the user has got a prefilled dossier, owned by themselves" do
+        let!(:user) { create(:user, password: password) }
+
+        before do
+          click_on "J’ai déjà un compte"
+          sign_in_with user.email, password
+
+          click_on "Commencer la démarche"
+        end
+      end
+    end
+
+    context 'when the user signs up with email and password' do
+      it_behaves_like "the user has got a prefilled dossier, owned by themselves" do
+        let(:user_email) { generate :user_email }
+        let(:user) { User.find_by(email: user_email) }
+
+        before do
+          click_on "Créer un compte #{APPLICATION_NAME}"
+
+          sign_up_with user_email, password
+          expect(page).to have_content "nous avons besoin de vérifier votre adresse #{user_email}"
+
+          click_confirmation_link_for user_email
+          expect(page).to have_content('Votre compte a bien été confirmé.')
+
+          click_on "Commencer la démarche"
+        end
+      end
+    end
+
+    context 'when the user signs up with FranceConnect' do
+      it_behaves_like "the user has got a prefilled dossier, owned by themselves" do
+        let(:user) { User.last }
+
+        before do
+          allow_any_instance_of(FranceConnectParticulierClient).to receive(:authorization_uri).and_return(france_connect_particulier_callback_path(code: "c0d3"))
+          allow(FranceConnectService).to receive(:retrieve_user_informations_particulier).and_return(build(:france_connect_information))
+
+          page.find('.fr-connect').click
+
+          click_on "Commencer la démarche"
+        end
+      end
+    end
+  end
+end
diff --git a/spec/system/users/dossier_prefill_post_spec.rb b/spec/system/users/dossier_prefill_post_spec.rb
new file mode 100644
index 000000000..8b495da8d
--- /dev/null
+++ b/spec/system/users/dossier_prefill_post_spec.rb
@@ -0,0 +1,102 @@
+describe 'Prefilling a dossier (with a POST request):' do
+  let(:password) { 'my-s3cure-p4ssword' }
+
+  let(:procedure) { create(:procedure, :published) }
+  let(:dossier) { procedure.dossiers.last }
+
+  let(:type_de_champ_text) { create(:type_de_champ_text, procedure: procedure) }
+  let(:type_de_champ_phone) { create(:type_de_champ_phone, procedure: procedure) }
+  let(:text_value) { "My Neighbor Totoro is the best movie ever" }
+  let(:phone_value) { "invalid phone value" }
+
+  scenario "the user get the URL of a prefilled orphan brouillon dossier" do
+    dossier_url = create_and_prefill_dossier_with_post_request
+
+    expect(dossier_url).to eq(commencer_path(procedure.path, prefill_token: dossier.prefill_token))
+  end
+
+  describe 'visit the dossier URL' do
+    context 'when authenticated' do
+      it_behaves_like "the user has got a prefilled dossier, owned by themselves" do
+        let(:user) { create(:user, password: password) }
+
+        before do
+          visit "/users/sign_in"
+          sign_in_with user.email, password
+
+          visit create_and_prefill_dossier_with_post_request
+
+          expect(page).to have_content('Vous avez un dossier prérempli')
+          click_on 'Continuer à remplir mon dossier'
+        end
+      end
+    end
+
+    context 'when unauthenticated' do
+      before { visit create_and_prefill_dossier_with_post_request }
+
+      context 'when the user signs in with email and password' do
+        it_behaves_like "the user has got a prefilled dossier, owned by themselves" do
+          let(:user) { create(:user, password: password) }
+
+          before do
+            click_on "J’ai déjà un compte"
+            sign_in_with user.email, password
+
+            expect(page).to have_content('Vous avez un dossier prérempli')
+            click_on 'Continuer à remplir mon dossier'
+          end
+        end
+      end
+
+      context 'when the user signs up with email and password' do
+        it_behaves_like "the user has got a prefilled dossier, owned by themselves" do
+          let(:user_email) { generate :user_email }
+          let(:user) { User.find_by(email: user_email) }
+
+          before do
+            click_on "Créer un compte #{APPLICATION_NAME}"
+
+            sign_up_with user_email, password
+            expect(page).to have_content "nous avons besoin de vérifier votre adresse #{user_email}"
+
+            click_confirmation_link_for user_email
+            expect(page).to have_content('Votre compte a bien été confirmé.')
+
+            expect(page).to have_content('Vous avez un dossier prérempli')
+            click_on 'Continuer à remplir mon dossier'
+          end
+        end
+      end
+
+      context 'when the user signs up with FranceConnect' do
+        it_behaves_like "the user has got a prefilled dossier, owned by themselves" do
+          let(:user) { User.last }
+
+          before do
+            allow_any_instance_of(FranceConnectParticulierClient).to receive(:authorization_uri).and_return(france_connect_particulier_callback_path(code: "c0d3"))
+            allow(FranceConnectService).to receive(:retrieve_user_informations_particulier).and_return(build(:france_connect_information))
+
+            page.find('.fr-connect').click
+
+            expect(page).to have_content('Vous avez un dossier prérempli')
+            click_on 'Continuer à remplir mon dossier'
+          end
+        end
+      end
+    end
+  end
+
+  private
+
+  def create_and_prefill_dossier_with_post_request
+    session = ActionDispatch::Integration::Session.new(Rails.application)
+    session.post api_public_v1_dossiers_path(procedure),
+      headers: { "Content-Type" => "application/json" },
+      params: {
+        "champ_#{type_de_champ_text.to_typed_id}" => text_value,
+        "champ_#{type_de_champ_phone.to_typed_id}" => phone_value
+      }.to_json
+    JSON.parse(session.response.body)["dossier_url"].gsub("http://www.example.com", "")
+  end
+end
diff --git a/spec/system/users/dossier_prefill_spec.rb b/spec/system/users/dossier_prefill_spec.rb
deleted file mode 100644
index 386feeba5..000000000
--- a/spec/system/users/dossier_prefill_spec.rb
+++ /dev/null
@@ -1,80 +0,0 @@
-describe 'Prefilling a dossier:' do
-  let(:password) { 'my-s3cure-p4ssword' }
-  let(:siret) { '41816609600051' }
-
-  let(:procedure) { create(:procedure, :published, opendata: true) }
-  let(:dossier) { procedure.dossiers.last }
-
-  let(:type_de_champ_text) { create(:type_de_champ_text, procedure: procedure) }
-  let(:type_de_champ_phone) { create(:type_de_champ_phone, procedure: procedure) }
-  let(:text_value) { "My Neighbor Totoro is the best movie ever" }
-  let(:phone_value) { "invalid phone value" }
-
-  before do
-    stub_request(:get, /https:\/\/entreprise.api.gouv.fr\/v2\/etablissements\/#{siret}/)
-      .to_return(status: 200, body: File.read('spec/fixtures/files/api_entreprise/etablissements.json'))
-
-    visit commencer_path(
-      path: procedure.path,
-      "champ_#{type_de_champ_text.to_typed_id}" => text_value,
-      "champ_#{type_de_champ_phone.to_typed_id}" => phone_value
-    )
-  end
-
-  shared_examples "the user has got a prefilled dossier" do
-    scenario "the user has got a prefilled dossier" do
-      click_on "Commencer la démarche"
-
-      expect(page).to have_current_path siret_dossier_path(procedure.dossiers.last)
-      fill_in 'Numéro SIRET', with: siret
-      click_on 'Valider'
-
-      expect(page).to have_current_path(etablissement_dossier_path(dossier))
-      expect(page).to have_content('OCTO TECHNOLOGY')
-      click_on 'Continuer avec ces informations'
-
-      expect(page).to have_current_path(brouillon_dossier_path(dossier))
-      expect(page).to have_field(type_de_champ_text.libelle, with: text_value)
-      expect(page).to have_field(type_de_champ_phone.libelle, with: phone_value)
-      expect(page).to have_css('.field_with_errors', text: type_de_champ_phone.libelle)
-    end
-  end
-
-  context 'when the user signs in with email and password' do
-    it_behaves_like "the user has got a prefilled dossier" do
-      let!(:user) { create(:user, password: password) }
-
-      before do
-        click_on "J’ai déjà un compte"
-        sign_in_with user.email, password
-      end
-    end
-  end
-
-  context 'when the user signs up with email and password' do
-    it_behaves_like "the user has got a prefilled dossier" do
-      let(:user_email) { generate :user_email }
-
-      before do
-        click_on "Créer un compte #{APPLICATION_NAME}"
-
-        sign_up_with user_email, password
-        expect(page).to have_content "nous avons besoin de vérifier votre adresse #{user_email}"
-
-        click_confirmation_link_for user_email
-        expect(page).to have_content('Votre compte a bien été confirmé.')
-      end
-    end
-  end
-
-  context 'when the user signs up with FranceConnect' do
-    it_behaves_like "the user has got a prefilled dossier" do
-      before do
-        allow_any_instance_of(FranceConnectParticulierClient).to receive(:authorization_uri).and_return(france_connect_particulier_callback_path(code: "c0d3"))
-        allow(FranceConnectService).to receive(:retrieve_user_informations_particulier).and_return(build(:france_connect_information))
-
-        page.find('.fr-connect').click
-      end
-    end
-  end
-end