diff --git a/python/gtsam/preamble/base.h b/python/gtsam/preamble/base.h
index affb03ffa..d07a75f6f 100644
--- a/python/gtsam/preamble/base.h
+++ b/python/gtsam/preamble/base.h
@@ -10,5 +10,3 @@
  * Without this they will be automatically converted to a Python object, and all
  * mutations on Python side will not be reflected on C++.
  */
-
-PYBIND11_MAKE_OPAQUE(std::vector<gtsam::Matrix>);  // JacobianVector