diff --git a/addons/product/models/product_supplierinfo.py b/addons/product/models/product_supplierinfo.py
index af0a94f6f2d..6bf474a2bfa 100644
--- a/addons/product/models/product_supplierinfo.py
+++ b/addons/product/models/product_supplierinfo.py
@@ -86,7 +86,8 @@ class SupplierInfo(models.Model):
 
     def _sanitize_vals(self, vals):
         """Sanitize vals to sync product variant & template on read/write."""
-        if 'product_id' in vals and 'product_tmpl_id' not in vals:
+        # add product's product_tmpl_id if none present in vals
+        if  vals.get('product_id') and not vals.get('product_tmpl_id'):
             product = self.env['product.product'].browse(vals['product_id'])
             vals['product_tmpl_id'] = product.product_tmpl_id.id
 
diff --git a/addons/product/tests/test_seller.py b/addons/product/tests/test_seller.py
index 42deb5ec410..7de18ed985f 100644
--- a/addons/product/tests/test_seller.py
+++ b/addons/product/tests/test_seller.py
@@ -146,3 +146,6 @@ class TestSeller(TransactionCase):
         }])
         self.assertEqual(vendors, self.product_consu.seller_ids,
             "Sellers of a product should be listed in the product's seller_ids")
+        vendors.write({'product_id': False})
+        self.assertEqual(vendors, self.product_consu.seller_ids,
+            "Setting the product_id to False shouldn't affect seller_ids.")