diff --git a/tailbone/views/inventory.py b/tailbone/views/inventory.py
index be276b8e..83cc77a3 100644
--- a/tailbone/views/inventory.py
+++ b/tailbone/views/inventory.py
@@ -221,6 +221,9 @@ class InventoryBatchView(BatchMasterView):
         else:
             del fs.complete
 
+    # TODO: document this, maybe move it etc.
+    unknown_product_creates_row = True
+
     # TODO: this view can create new rows, with only a GET query.  that should
     # probably be changed to require POST; for now we just require the "create
     # batch row" perm and call it good..
@@ -243,14 +246,19 @@ class InventoryBatchView(BatchMasterView):
                 product = api.get_product_by_upc(self.Session(), provided)
                 if not product:
                     product = api.get_product_by_upc(self.Session(), checked)
-                row = model.InventoryBatchRow()
-                if product:
-                    row.product = product
-                    row.upc = product.upc
+                if product or self.unknown_product_creates_row:
+                    row = model.InventoryBatchRow()
+                    if product:
+                        row.product = product
+                        row.upc = product.upc
+                    else:
+                        row.upc = provided # TODO: why not 'checked' instead? how to choose?
+                        row.description = "(unknown product)"
+                    self.handler.add_row(batch, row)
+
                 else:
-                    row.upc = provided # TODO: why not 'checked' instead? how to choose?
-                    row.description = "(unknown product)"
-                self.handler.add_row(batch, row)
+                    self.request.session.flash("Product not found: {}".format(upc), 'error')
+                    return self.redirect(self.get_action_url('view', batch, mobile=True))
 
             else:
                 self.request.session.flash("UPC has too many digits ({}): {}".format(len(upc), upc), 'error')