diff --git a/addons/account/models/account_reconcile_model.py b/addons/account/models/account_reconcile_model.py
index 65e05df6c40747af8f889659ff220c701f4a2041..2398e14d41552f46b792fdfd9f0825a9c253cfbf 100644
--- a/addons/account/models/account_reconcile_model.py
+++ b/addons/account/models/account_reconcile_model.py
@@ -345,7 +345,7 @@ class AccountReconcileModel(models.Model):
     match_partner_category_ids = fields.Many2many('res.partner.category', string='Matching categories',
         help='The reconciliation model will only be applied to the selected customer/vendor categories.')
 
-    line_ids = fields.One2many('account.reconcile.model.line', 'model_id')
+    line_ids = fields.One2many('account.reconcile.model.line', 'model_id', copy=True)
     partner_mapping_line_ids = fields.One2many(string="Partner Mapping Lines",
                                                comodel_name='account.reconcile.model.partner.mapping',
                                                inverse_name='model_id',