diff --git a/addons/stock/models/stock_picking.py b/addons/stock/models/stock_picking.py
index fc6a3779da4..ba59869ea1e 100644
--- a/addons/stock/models/stock_picking.py
+++ b/addons/stock/models/stock_picking.py
@@ -363,7 +363,8 @@ class Picking(models.Model):
     is_locked = fields.Boolean(default=True, help='When the picking is not done this allows changing the '
                                'initial demand. When the picking is done this allows '
                                'changing the done quantities.')
-    product_id = fields.Many2one('product.product', 'Product', related='move_lines.product_id', readonly=False)
+    # Used to search on pickings
+    product_id = fields.Many2one('product.product', 'Product', related='move_lines.product_id', readonly=True)
     show_operations = fields.Boolean(compute='_compute_show_operations')
     show_reserved = fields.Boolean(related='picking_type_id.show_reserved')
     show_lots_text = fields.Boolean(compute='_compute_show_lots_text')