diff --git a/gtsam/inference/Key.cpp b/gtsam/inference/Key.cpp
index 15d633eeb..073a545c3 100644
--- a/gtsam/inference/Key.cpp
+++ b/gtsam/inference/Key.cpp
@@ -28,6 +28,7 @@ namespace gtsam {
 
 /// Assign default key formatter
 KeyFormatter DefaultKeyFormatter = &_defaultKeyFormatter;
+KeyFormatter MultiRobotKeyFormatter = &_multirobotKeyFormatter;
 
 /* ************************************************************************* */
 string _defaultKeyFormatter(Key key) {
diff --git a/gtsam/inference/Key.h b/gtsam/inference/Key.h
index a02d018f5..59f5ecf50 100644
--- a/gtsam/inference/Key.h
+++ b/gtsam/inference/Key.h
@@ -57,8 +57,7 @@ GTSAM_EXPORT std::string _multirobotKeyFormatter(gtsam::Key key);
 /// formatter in print functions.
 ///
 /// Checks for LabeledSymbol, Symbol and then plain keys, in order.
-static const gtsam::KeyFormatter MultiRobotKeyFormatter =
-    &_multirobotKeyFormatter;
+extern GTSAM_EXPORT KeyFormatter MultiRobotKeyFormatter; 
 
 /// To use the key_formatter on Keys, they must be wrapped in a StreamedKey.
 struct StreamedKey {