diff --git a/gtsam/geometry/Cal3Bundler.h b/gtsam/geometry/Cal3Bundler.h
index b240603fc..82b5ec91d 100644
--- a/gtsam/geometry/Cal3Bundler.h
+++ b/gtsam/geometry/Cal3Bundler.h
@@ -41,6 +41,9 @@ class GTSAM_EXPORT Cal3Bundler : public Cal3 {
  public:
   enum { dimension = 3 };
 
+  ///< shared pointer to stereo calibration object
+  using shared_ptr = boost::shared_ptr<Cal3Bundler>;
+
   /// @name Standard Constructors
   /// @{
 
diff --git a/gtsam/geometry/Cal3DS2.h b/gtsam/geometry/Cal3DS2.h
index f756cba5e..affce0819 100644
--- a/gtsam/geometry/Cal3DS2.h
+++ b/gtsam/geometry/Cal3DS2.h
@@ -37,6 +37,9 @@ class GTSAM_EXPORT Cal3DS2 : public Cal3DS2_Base {
  public:
   enum { dimension = 9 };
 
+  ///< shared pointer to stereo calibration object
+  using shared_ptr = boost::shared_ptr<Cal3DS2>;
+
   /// @name Standard Constructors
   /// @{
 
diff --git a/gtsam/geometry/Cal3DS2_Base.h b/gtsam/geometry/Cal3DS2_Base.h
index a9b09cf46..b583234fd 100644
--- a/gtsam/geometry/Cal3DS2_Base.h
+++ b/gtsam/geometry/Cal3DS2_Base.h
@@ -47,6 +47,9 @@ class GTSAM_EXPORT Cal3DS2_Base : public Cal3 {
  public:
   enum { dimension = 9 };
 
+  ///< shared pointer to stereo calibration object
+  using shared_ptr = boost::shared_ptr<Cal3DS2_Base>;
+
   /// @name Standard Constructors
   /// @{
 
diff --git a/gtsam/geometry/Cal3Unified.h b/gtsam/geometry/Cal3Unified.h
index f07ca0a54..e93d313c8 100644
--- a/gtsam/geometry/Cal3Unified.h
+++ b/gtsam/geometry/Cal3Unified.h
@@ -52,6 +52,9 @@ class GTSAM_EXPORT Cal3Unified : public Cal3DS2_Base {
  public:
   enum { dimension = 10 };
 
+  ///< shared pointer to stereo calibration object
+  using shared_ptr = boost::shared_ptr<Cal3Unified>;
+
   /// @name Standard Constructors
   /// @{