diff --git a/odoo/addons/test_inherits/models.py b/odoo/addons/test_inherits/models.py
index c9eeff60904..b503e8c173b 100644
--- a/odoo/addons/test_inherits/models.py
+++ b/odoo/addons/test_inherits/models.py
@@ -13,6 +13,7 @@ class Unit(models.Model):
     surname = fields.Char(compute='_compute_surname')
     line_ids = fields.One2many('test.unit.line', 'unit_id')
     readonly_name = fields.Char('Readonly Name', readonly=True)
+    size = fields.Integer()
 
     @api.depends('name')
     def _compute_surname(self):
@@ -38,6 +39,7 @@ class Box(models.Model):
     unit_id = fields.Many2one('test.unit', 'Unit', required=True,
                               ondelete='cascade')
     field_in_box = fields.Char('Field1')
+    size = fields.Integer()
 
 
 # We add a third level of _inherits
diff --git a/odoo/addons/test_inherits/tests/test_inherits.py b/odoo/addons/test_inherits/tests/test_inherits.py
index 4c32db71864..9822ab19020 100644
--- a/odoo/addons/test_inherits/tests/test_inherits.py
+++ b/odoo/addons/test_inherits/tests/test_inherits.py
@@ -17,6 +17,24 @@ class test_inherits(common.TransactionCase):
         self.assertEqual(pallet.field_in_box, 'box')
         self.assertEqual(pallet.field_in_pallet, 'pallet')
 
+    def test_create_3_levels_inherits_with_defaults(self):
+        unit = self.env['test.unit'].create({
+            'name': 'U',
+            'state': 'a',
+            'size': 1,
+        })
+        ctx = {
+            'default_state': 'b',       # 'state' is inherited from 'test.unit'
+            'default_size': 2,          # 'size' is inherited from 'test.box'
+        }
+        pallet = self.env['test.pallet'].with_context(ctx).create({
+            'name': 'P',
+            'unit_id': unit.id,         # grand-parent field is set
+        })
+        # default 'state' should be ignored, but default 'size' should not
+        self.assertEqual(pallet.state, 'a')
+        self.assertEqual(pallet.size, 2)
+
     def test_read_3_levels_inherits(self):
         """ Check that we can read an inherited field on 3 levels """
         pallet = self.env.ref('test_inherits.pallet_a')
diff --git a/odoo/models.py b/odoo/models.py
index 0a3a08109a2..6489e13e65d 100644
--- a/odoo/models.py
+++ b/odoo/models.py
@@ -1807,18 +1807,33 @@ class BaseModel(MetaModel('DummyModel', (object,), {'_register': False})):
     @api.model
     def _add_missing_default_values(self, values):
         # avoid overriding inherited values when parent is set
-        avoid_models = {
-            parent_model
-            for parent_model, parent_field in self._inherits.items()
-            if parent_field in values
-        }
+        avoid_models = set()
+
+        def collect_models_to_avoid(model):
+            for parent_mname, parent_fname in model._inherits.items():
+                if parent_fname in values:
+                    avoid_models.add(parent_mname)
+                else:
+                    # manage the case where an ancestor parent field is set
+                    collect_models_to_avoid(self.env[parent_mname])
+
+        collect_models_to_avoid(self)
+
+        def avoid(field):
+            # check whether the field is inherited from one of avoid_models
+            if avoid_models:
+                while field.inherited:
+                    field = field.related_field
+                    if field.model_name in avoid_models:
+                        return True
+            return False
 
         # compute missing fields
         missing_defaults = {
             name
             for name, field in self._fields.items()
             if name not in values
-            if not (field.inherited and field.related_field.model_name in avoid_models)
+            if not avoid(field)
         }
 
         if not missing_defaults: