diff --git a/src/appleseed-max-impl/disneymtl/appleseeddisneymtl.cpp b/src/appleseed-max-impl/disneymtl/appleseeddisneymtl.cpp
index 6404ba0..9dd4f62 100644
--- a/src/appleseed-max-impl/disneymtl/appleseeddisneymtl.cpp
+++ b/src/appleseed-max-impl/disneymtl/appleseeddisneymtl.cpp
@@ -83,6 +83,7 @@ namespace
 
     enum ParamId
     {
+        // Changing the order of these parameters WILL break compatibility.
         ParamIdBaseColor,
         ParamIdBaseColorTexmap,
         ParamIdMetallic,
diff --git a/src/appleseed-max-impl/disneymtl/datachunks.h b/src/appleseed-max-impl/disneymtl/datachunks.h
index 52e8b3e..e1cb820 100644
--- a/src/appleseed-max-impl/disneymtl/datachunks.h
+++ b/src/appleseed-max-impl/disneymtl/datachunks.h
@@ -31,6 +31,11 @@
 // appleseed.foundation headers.
 #include "foundation/platform/windows.h"
 
+//
+// Changing the values of these constants WILL break compatibility
+// with 3ds Max files saved with older versions of the plugin.
+//
+
 const USHORT ChunkFileFormatVersion                 = 0x0001;
 
 const USHORT ChunkMtlBase                           = 0x1000;
diff --git a/src/appleseed-max-impl/glassmtl/appleseedglassmtl.cpp b/src/appleseed-max-impl/glassmtl/appleseedglassmtl.cpp
index 91895d1..e0e6136 100644
--- a/src/appleseed-max-impl/glassmtl/appleseedglassmtl.cpp
+++ b/src/appleseed-max-impl/glassmtl/appleseedglassmtl.cpp
@@ -89,6 +89,7 @@ namespace
 
     enum ParamId
     {
+        // Changing the order of these parameters WILL break compatibility.
         ParamIdSurfaceColor,
         ParamIdSurfaceColorTexmap,
         ParamIdReflectionTint,
diff --git a/src/appleseed-max-impl/glassmtl/datachunks.h b/src/appleseed-max-impl/glassmtl/datachunks.h
index 91695f2..0eade6a 100644
--- a/src/appleseed-max-impl/glassmtl/datachunks.h
+++ b/src/appleseed-max-impl/glassmtl/datachunks.h
@@ -31,6 +31,11 @@
 // appleseed.foundation headers.
 #include "foundation/platform/windows.h"
 
+//
+// Changing the values of these constants WILL break compatibility
+// with 3ds Max files saved with older versions of the plugin.
+//
+
 const USHORT ChunkFileFormatVersion                 = 0x0001;
 
 const USHORT ChunkMtlBase                           = 0x1000;
diff --git a/src/appleseed-max-impl/lightmtl/appleseedlightmtl.cpp b/src/appleseed-max-impl/lightmtl/appleseedlightmtl.cpp
index 2a48bb3..bf6290a 100644
--- a/src/appleseed-max-impl/lightmtl/appleseedlightmtl.cpp
+++ b/src/appleseed-max-impl/lightmtl/appleseedlightmtl.cpp
@@ -81,6 +81,7 @@ namespace
 
     enum ParamId
     {
+        // Changing the order of these parameters WILL break compatibility.
         ParamIdLightColor,
         ParamIdLightColorTexmap,
         ParamIdLightPower,
diff --git a/src/appleseed-max-impl/lightmtl/datachunks.h b/src/appleseed-max-impl/lightmtl/datachunks.h
index 91695f2..0eade6a 100644
--- a/src/appleseed-max-impl/lightmtl/datachunks.h
+++ b/src/appleseed-max-impl/lightmtl/datachunks.h
@@ -31,6 +31,11 @@
 // appleseed.foundation headers.
 #include "foundation/platform/windows.h"
 
+//
+// Changing the values of these constants WILL break compatibility
+// with 3ds Max files saved with older versions of the plugin.
+//
+
 const USHORT ChunkFileFormatVersion                 = 0x0001;
 
 const USHORT ChunkMtlBase                           = 0x1000;
diff --git a/src/appleseed-max-impl/sssmtl/appleseedsssmtl.cpp b/src/appleseed-max-impl/sssmtl/appleseedsssmtl.cpp
index ce5d3e0..5fa413f 100644
--- a/src/appleseed-max-impl/sssmtl/appleseedsssmtl.cpp
+++ b/src/appleseed-max-impl/sssmtl/appleseedsssmtl.cpp
@@ -88,6 +88,7 @@ namespace
 
     enum ParamId
     {
+        // Changing the order of these parameters WILL break compatibility.
         ParamIdSSSColor,
         ParamIdSSSColorTexmap,
         ParamIdSSSScatteringColor,
diff --git a/src/appleseed-max-impl/sssmtl/datachunks.h b/src/appleseed-max-impl/sssmtl/datachunks.h
index 91695f2..0eade6a 100644
--- a/src/appleseed-max-impl/sssmtl/datachunks.h
+++ b/src/appleseed-max-impl/sssmtl/datachunks.h
@@ -31,6 +31,11 @@
 // appleseed.foundation headers.
 #include "foundation/platform/windows.h"
 
+//
+// Changing the values of these constants WILL break compatibility
+// with 3ds Max files saved with older versions of the plugin.
+//
+
 const USHORT ChunkFileFormatVersion                 = 0x0001;
 
 const USHORT ChunkMtlBase                           = 0x1000;