diff --git a/tf2onnx/tflite_utils.py b/tf2onnx/tflite_utils.py
index 82cd2f5d8..8c4909e15 100644
--- a/tf2onnx/tflite_utils.py
+++ b/tf2onnx/tflite_utils.py
@@ -171,13 +171,14 @@ def parse_tflite_graph(tflite_g, opcodes_map, model, input_prefix=''):
         tensor_names[i] = name
         name_to_tensor[name] = tensor
 
-        if tensor.ShapeIsNone():
-            output_shapes[name] = None
-        elif tensor.ShapeSignatureIsNone():
+        if not tensor.ShapeSignatureIsNone():
+            output_shapes[name] = tensor.ShapeSignatureAsNumpy().tolist()
+        elif not tensor.ShapeIsNone() and len(tensor.ShapeAsNumpy().tolist()) > 0:
             # The shape signature uses -1 to signify unknown dims. Old models don't have this and use Shape instead.
+            # Annoyingly, an empty shape can actually mean the rank is unknown.
             output_shapes[name] = tensor.ShapeAsNumpy().tolist()
         else:
-            output_shapes[name] = tensor.ShapeSignatureAsNumpy().tolist()
+            output_shapes[name] = None
         buf = model.Buffers(tensor.Buffer())
         dtypes[name] = map_tflite_dtype_to_onnx(tensor.Type())
         if not buf.DataIsNone() and tensor.Buffer() > 0: