diff --git a/gtsam/base/ConcurrentMap.h b/gtsam/base/ConcurrentMap.h
index 03687f5624..8ce44dda39 100644
--- a/gtsam/base/ConcurrentMap.h
+++ b/gtsam/base/ConcurrentMap.h
@@ -85,6 +85,8 @@ class ConcurrentMap : public ConcurrentMapBase<KEY,VALUE> {
   /** Copy constructor from the base map class */
   ConcurrentMap(const Base& x) : Base(x) {}
 
+  ConcurrentMap& operator=(const ConcurrentMap& other) = default;
+
   /** Handy 'exists' function */
   bool exists(const KEY& e) const { return this->count(e); }
 
diff --git a/gtsam/base/FastList.h b/gtsam/base/FastList.h
index 1a3b9ed3fe..821575ca93 100644
--- a/gtsam/base/FastList.h
+++ b/gtsam/base/FastList.h
@@ -62,6 +62,8 @@ class FastList: public std::list<VALUE, typename internal::FastDefaultAllocator<
   /// Construct from c++11 initializer list:
   FastList(std::initializer_list<VALUE> l) : Base(l) {}
 
+  FastList& operator=(const FastList& other) = default;
+
 #ifdef GTSAM_ALLOCATOR_BOOSTPOOL
   /** Copy constructor from a standard STL container */
   FastList(const std::list<VALUE>& x) {
diff --git a/gtsam/base/FastMap.h b/gtsam/base/FastMap.h
index 75998fd2fa..30052908d6 100644
--- a/gtsam/base/FastMap.h
+++ b/gtsam/base/FastMap.h
@@ -54,6 +54,8 @@ class FastMap : public std::map<KEY, VALUE, std::less<KEY>,
   /** Copy constructor from another FastMap */
   FastMap(const FastMap<KEY,VALUE>& x) : Base(x) {}
 
+  FastMap& operator=(const FastMap<KEY,VALUE>& x) = default;
+
   /** Copy constructor from the base map class */
   FastMap(const Base& x) : Base(x) {}
 
diff --git a/gtsam/base/FastSet.h b/gtsam/base/FastSet.h
index 9a2f624974..1a2627e247 100644
--- a/gtsam/base/FastSet.h
+++ b/gtsam/base/FastSet.h
@@ -80,6 +80,8 @@ class FastSet: public std::set<VALUE, std::less<VALUE>,
   Base(x) {
   }
 
+  FastSet& operator=(const FastSet& other) = default;
+
 #ifdef GTSAM_ALLOCATOR_BOOSTPOOL
   /** Copy constructor from a standard STL container */
   FastSet(const std::set<VALUE>& x) {
diff --git a/gtsam/base/GenericValue.h b/gtsam/base/GenericValue.h
index 62ea8ec39f..396ca16ba7 100644
--- a/gtsam/base/GenericValue.h
+++ b/gtsam/base/GenericValue.h
@@ -56,9 +56,10 @@ class GenericValue: public Value {
   GenericValue(){}
 
   /// Construct from value
-  GenericValue(const T& value) :
-      value_(value) {
-  }
+  GenericValue(const T& value) : Value(),
+      value_(value) {}
+
+  GenericValue(const GenericValue& other) = default;
 
   /// Return a constant value
   const T& value() const {
@@ -112,7 +113,7 @@ class GenericValue: public Value {
      * Clone this value (normal clone on the heap, delete with 'delete' operator)
      */
     std::shared_ptr<Value> clone() const override {
-		return std::allocate_shared<GenericValue>(Eigen::aligned_allocator<GenericValue>(), *this);
+      return std::allocate_shared<GenericValue>(Eigen::aligned_allocator<GenericValue>(), *this);
     }
 
     /// Generic Value interface version of retract
diff --git a/gtsam/base/Value.h b/gtsam/base/Value.h
index 09a3f4878a..e80b9d4a4d 100644
--- a/gtsam/base/Value.h
+++ b/gtsam/base/Value.h
@@ -38,6 +38,9 @@ namespace gtsam {
    */
   class GTSAM_EXPORT Value {
   public:
+    // todo - not sure if valid
+    Value() = default;
+    Value(const Value& other) = default;
 
     /** Clone this value in a special memory pool, must be deleted with Value::deallocate_, *not* with the 'delete' operator. */
     virtual Value* clone_() const = 0;
diff --git a/gtsam/discrete/SignatureParser.cpp b/gtsam/discrete/SignatureParser.cpp
index 31e4253925..8e0221f015 100644
--- a/gtsam/discrete/SignatureParser.cpp
+++ b/gtsam/discrete/SignatureParser.cpp
@@ -38,7 +38,7 @@ std::optional<Row> static ParseConditional(const std::string& token) {
   } catch (...) {
     return std::nullopt;
   }
-  return std::move(row);
+  return row;
 }
 
 std::optional<Table> static ParseConditionalTable(
@@ -62,7 +62,7 @@ std::optional<Table> static ParseConditionalTable(
       }
     }
   }
-  return std::move(table);
+  return table;
 }
 
 std::vector<std::string> static Tokenize(const std::string& str) {
diff --git a/gtsam/geometry/Pose2.h b/gtsam/geometry/Pose2.h
index 3f85a7f42e..da7bc922e8 100644
--- a/gtsam/geometry/Pose2.h
+++ b/gtsam/geometry/Pose2.h
@@ -60,7 +60,10 @@ class GTSAM_EXPORT Pose2: public LieGroup<Pose2, 3> {
   }
 
   /** copy constructor */
-  Pose2(const Pose2& pose) : r_(pose.r_), t_(pose.t_) {}
+  Pose2(const Pose2& pose) = default;
+  //  : r_(pose.r_), t_(pose.t_) {}
+
+  Pose2& operator=(const Pose2& other) = default;
 
   /**
    * construct from (x,y,theta)
diff --git a/gtsam/geometry/Pose3.h b/gtsam/geometry/Pose3.h
index 5805ce41b1..54bdd7f4c4 100644
--- a/gtsam/geometry/Pose3.h
+++ b/gtsam/geometry/Pose3.h
@@ -55,9 +55,10 @@ class GTSAM_EXPORT Pose3: public LieGroup<Pose3, 6> {
   Pose3() : R_(traits<Rot3>::Identity()), t_(traits<Point3>::Identity()) {}
 
   /** Copy constructor */
-  Pose3(const Pose3& pose) :
-      R_(pose.R_), t_(pose.t_) {
-  }
+  Pose3(const Pose3& pose) = default;
+  //  :
+  //     R_(pose.R_), t_(pose.t_) {
+  // }
 
   /** Construct from R,t */
   Pose3(const Rot3& R, const Point3& t) :
diff --git a/gtsam/geometry/Rot2.h b/gtsam/geometry/Rot2.h
index 07f328b96d..7a6f25c4d0 100644
--- a/gtsam/geometry/Rot2.h
+++ b/gtsam/geometry/Rot2.h
@@ -52,11 +52,14 @@ namespace gtsam {
     Rot2() : c_(1.0), s_(0.0) {}
     
     /** copy constructor */
-    Rot2(const Rot2& r) : Rot2(r.c_, r.s_) {}
+    Rot2(const Rot2& r) = default;
+    //  : Rot2(r.c_, r.s_) {}
 
     /// Constructor from angle in radians == exponential map at identity
     Rot2(double theta) : c_(cos(theta)), s_(sin(theta)) {}
 
+    // Rot2& operator=(const gtsam::Rot2& other) = default;
+
     /// Named constructor from angle in radians
     static Rot2 fromAngle(double theta) {
       return Rot2(theta);
diff --git a/gtsam/linear/ConjugateGradientSolver.h b/gtsam/linear/ConjugateGradientSolver.h
index 46d49ca4fc..aaec039e96 100644
--- a/gtsam/linear/ConjugateGradientSolver.h
+++ b/gtsam/linear/ConjugateGradientSolver.h
@@ -69,6 +69,8 @@ struct GTSAM_EXPORT ConjugateGradientParameters
         epsilon_abs(p.epsilon_abs),
         blas_kernel(GTSAM) {}
 
+  ConjugateGradientParameters& operator=(const ConjugateGradientParameters& other) = default;
+
 #ifdef GTSAM_ALLOW_DEPRECATED_SINCE_V43
   inline size_t getMinIterations() const { return minIterations; }
   inline size_t getMaxIterations() const { return maxIterations; }
diff --git a/gtsam/linear/HessianFactor.cpp b/gtsam/linear/HessianFactor.cpp
index 4e8ef804c0..1172dc2813 100644
--- a/gtsam/linear/HessianFactor.cpp
+++ b/gtsam/linear/HessianFactor.cpp
@@ -379,7 +379,7 @@ GaussianFactor::shared_ptr HessianFactor::negate() const {
   shared_ptr result = std::make_shared<This>(*this);
   // Negate the information matrix of the result
   result->info_.negate();
-  return std::move(result);
+  return result;
 }
 
 /* ************************************************************************* */
diff --git a/gtsam/linear/JacobianFactor.h b/gtsam/linear/JacobianFactor.h
index 4a5b6d5d1e..a9933374f2 100644
--- a/gtsam/linear/JacobianFactor.h
+++ b/gtsam/linear/JacobianFactor.h
@@ -117,6 +117,8 @@ namespace gtsam {
     /** Conversion from HessianFactor (does Cholesky to obtain Jacobian matrix) */
     explicit JacobianFactor(const HessianFactor& hf);
 
+    JacobianFactor& operator=(const JacobianFactor& jf) = default;
+
     /** default constructor for I/O */
     JacobianFactor();
 
diff --git a/gtsam/linear/NoiseModel.cpp b/gtsam/linear/NoiseModel.cpp
index 39666b46bc..2f693bbc41 100644
--- a/gtsam/linear/NoiseModel.cpp
+++ b/gtsam/linear/NoiseModel.cpp
@@ -64,7 +64,7 @@ std::optional<Vector> checkIfDiagonal(const Matrix& M) {
     Vector diagonal(n);
     for (j = 0; j < n; j++)
       diagonal(j) = M(j, j);
-    return std::move(diagonal);
+    return diagonal;
   }
 }
 
diff --git a/gtsam/linear/VectorValues.h b/gtsam/linear/VectorValues.h
index e60209a832..4728706c50 100644
--- a/gtsam/linear/VectorValues.h
+++ b/gtsam/linear/VectorValues.h
@@ -119,6 +119,8 @@ namespace gtsam {
     /// Constructor from Vector, with Scatter
     VectorValues(const Vector& c, const Scatter& scatter);
 
+    VectorValues& operator=(const VectorValues& other) = default;
+
     /** Create a VectorValues with the same structure as \c other, but filled with zeros. */
     static VectorValues Zero(const VectorValues& other);
 
diff --git a/gtsam/nonlinear/ExpressionFactor.h b/gtsam/nonlinear/ExpressionFactor.h
index 4f6648849b..df89f5b44c 100644
--- a/gtsam/nonlinear/ExpressionFactor.h
+++ b/gtsam/nonlinear/ExpressionFactor.h
@@ -149,7 +149,7 @@ class ExpressionFactor : public NoiseModelFactor {
       noiseModel_->WhitenSystem(Ab.matrix(), b);
     }
 
-    return std::move(factor);
+    return factor;
   }
 
   /// @return a deep copy of this factor
diff --git a/gtsam/slam/FrobeniusFactor.cpp b/gtsam/slam/FrobeniusFactor.cpp
index e70f64d969..982430d81e 100644
--- a/gtsam/slam/FrobeniusFactor.cpp
+++ b/gtsam/slam/FrobeniusFactor.cpp
@@ -61,7 +61,7 @@ ConvertNoiseModel(const SharedNoiseModel &model, size_t d, bool defaultToUnit) {
     return noiseModel::Robust::Create(
         noiseModel::mEstimator::Huber::Create(1.345), isoModel);
   } else {
-    return std::move(isoModel);
+    return isoModel;
   }
 }
 
diff --git a/gtsam_unstable/geometry/Pose3Upright.h b/gtsam_unstable/geometry/Pose3Upright.h
index 20e0fde5db..464f46928a 100644
--- a/gtsam_unstable/geometry/Pose3Upright.h
+++ b/gtsam_unstable/geometry/Pose3Upright.h
@@ -43,6 +43,7 @@ class GTSAM_UNSTABLE_EXPORT Pose3Upright {
   Pose3Upright(const Rot2& bearing, const Point3& t);
   Pose3Upright(double x, double y, double z, double theta);
   Pose3Upright(const Pose2& pose, double z);
+  Pose3Upright& operator=(const Pose3Upright& x) = default;
 
   /// Down-converts from a full Pose3
   Pose3Upright(const Pose3& fullpose);
diff --git a/gtsam_unstable/slam/Mechanization_bRn2.h b/gtsam_unstable/slam/Mechanization_bRn2.h
index 4714f2b6f1..3d91f6b0ea 100644
--- a/gtsam_unstable/slam/Mechanization_bRn2.h
+++ b/gtsam_unstable/slam/Mechanization_bRn2.h
@@ -35,9 +35,7 @@ class GTSAM_UNSTABLE_EXPORT Mechanization_bRn2 {
   }
 
   /// Copy constructor
-  Mechanization_bRn2(const Mechanization_bRn2& other) :
-      bRn_(other.bRn_), x_g_(other.x_g_), x_a_(other.x_a_) {
-  }
+  Mechanization_bRn2(const Mechanization_bRn2& other) = default;
 
   /// gravity in the body frame
   Vector3 b_g(double g_e) const {