diff --git a/libraries/entities/src/EntityItem.cpp b/libraries/entities/src/EntityItem.cpp
index ac349ad74d..9ac24b4324 100644
--- a/libraries/entities/src/EntityItem.cpp
+++ b/libraries/entities/src/EntityItem.cpp
@@ -2834,7 +2834,7 @@ DEFINE_PROPERTY_ACCESSOR(quint32, StaticCertificateVersion, staticCertificateVer
 uint32_t EntityItem::getDirtyFlags() const {
     uint32_t result;
     withReadLock([&] {
-        result = _flags & 0x0000ffff;
+        result = _flags & ~Simulation::SPECIAL_FLAGS;
     });
     return result;
 }
@@ -2842,14 +2842,14 @@ uint32_t EntityItem::getDirtyFlags() const {
 
 void EntityItem::markDirtyFlags(uint32_t mask) {
     withWriteLock([&] {
-        mask &= 0x0000ffff;
+        mask &= ~Simulation::SPECIAL_FLAGS;
         _flags |= mask;
     });
 }
 
 void EntityItem::clearDirtyFlags(uint32_t mask) {
     withWriteLock([&] {
-        mask &= 0x0000ffff;
+        mask &= ~Simulation::SPECIAL_FLAGS;
         _flags &= ~mask;
     });
 }
@@ -2857,21 +2857,21 @@ void EntityItem::clearDirtyFlags(uint32_t mask) {
 uint32_t EntityItem::getSpecialFlags() const {
     uint32_t result;
     withReadLock([&] {
-        result = _flags & 0xffff0000;
+        result = _flags & ~Simulation::DIRTY_FLAGS;
     });
     return result;
 }
 
 void EntityItem::markSpecialFlags(uint32_t mask) {
     withWriteLock([&] {
-        mask &= 0xffff0000;
+        mask &= ~Simulation::DIRTY_FLAGS;
         _flags |= mask;
     });
 }
 
 void EntityItem::clearSpecialFlags(uint32_t mask) {
     withWriteLock([&] {
-        mask &= 0xffff0000;
+        mask &= ~Simulation::DIRTY_FLAGS;
         _flags &= ~mask;
     });
 }
diff --git a/libraries/entities/src/SimulationFlags.h b/libraries/entities/src/SimulationFlags.h
index da82916fe3..c45b333b29 100644
--- a/libraries/entities/src/SimulationFlags.h
+++ b/libraries/entities/src/SimulationFlags.h
@@ -33,6 +33,22 @@ namespace Simulation {
 
     const uint32_t DIRTY_TRANSFORM = DIRTY_POSITION | DIRTY_ROTATION;
     const uint32_t DIRTY_VELOCITIES = DIRTY_LINEAR_VELOCITY | DIRTY_ANGULAR_VELOCITY;
+    const uint32_t SPECIAL_FLAGS = SPECIAL_FLAGS_NO_BOOTSTRAPPING;
+
+    const uint32_t DIRTY_FLAGS = DIRTY_POSITION |
+      DIRTY_ROTATION |
+      DIRTY_LINEAR_VELOCITY |
+      DIRTY_ANGULAR_VELOCITY |
+      DIRTY_MASS |
+      DIRTY_COLLISION_GROUP |
+      DIRTY_MOTION_TYPE |
+      DIRTY_SHAPE |
+      DIRTY_LIFETIME |
+      DIRTY_UPDATEABLE |
+      DIRTY_MATERIAL |
+      DIRTY_PHYSICS_ACTIVATION |
+      DIRTY_SIMULATOR_ID |
+      DIRTY_SIMULATION_OWNERSHIP_PRIORITY;
 };
 
 #endif // hifi_SimulationFlags_h