diff --git a/src/compressed_tensors/quantization/quant_config.py b/src/compressed_tensors/quantization/quant_config.py
index ea50f79d7..0218fec38 100644
--- a/src/compressed_tensors/quantization/quant_config.py
+++ b/src/compressed_tensors/quantization/quant_config.py
@@ -297,6 +297,12 @@ def requires_calibration_data(self):
             if scheme.output_activations is not None:
                 if not scheme.output_activations.dynamic:
                     return True
+            if (
+                scheme.weights is not None
+                and scheme.weights.observer is not None
+                and scheme.weights.observer.lower() == "imatrix_mse"
+            ):
+                return True
 
         return False