diff --git a/psyneulink/library/compositions/pytorchwrappers.py b/psyneulink/library/compositions/pytorchwrappers.py
index ab8ce37e7c..d481a4c537 100644
--- a/psyneulink/library/compositions/pytorchwrappers.py
+++ b/psyneulink/library/compositions/pytorchwrappers.py
@@ -232,7 +232,7 @@ def __init__(self,
                                                        self._composition._get_node_index(node),
                                                        device,
                                                        context=context)
-                pytorch_node._is_bias = any(input_port.default_input == DEFAULT_VARIABLE
+                pytorch_node._is_bias = all(input_port.default_input == DEFAULT_VARIABLE
                                             for input_port in node.input_ports)
             self.nodes_map[node] = pytorch_node
             self.wrapped_nodes.append(pytorch_node)