diff --git a/lib/al/include/Library/Camera/CameraDirector.h b/lib/al/include/Library/Camera/CameraDirector.h
index 11cefbe0..1bb2cfe0 100644
--- a/lib/al/include/Library/Camera/CameraDirector.h
+++ b/lib/al/include/Library/Camera/CameraDirector.h
@@ -33,7 +33,7 @@ class IUseAudioKeeper;
 class CameraRailHolder;
 class NameToCameraParamTransferFunc;
 
-class CameraDirector : public HioNode, IUseExecutor {
+class CameraDirector : public HioNode, public IUseExecutor {
 public:
     CameraDirector(s32 maxCameras);
     virtual ~CameraDirector();
diff --git a/lib/al/include/Library/LiveActor/LiveActorGroup.h b/lib/al/include/Library/LiveActor/LiveActorGroup.h
index d06ef033..2cc0376f 100755
--- a/lib/al/include/Library/LiveActor/LiveActorGroup.h
+++ b/lib/al/include/Library/LiveActor/LiveActorGroup.h
@@ -37,7 +37,7 @@ private:
 };
 
 template <class T>
-class DeriveActorGroup : LiveActorGroup {
+class DeriveActorGroup : public LiveActorGroup {
 public:
     s32 registerActor(T* actor) { LiveActorGroup::registerActor(actor); }
     void removeActor(const T* actor) { LiveActorGroup::removeActor(actor); }
diff --git a/lib/al/include/Library/Scene/GameDataHolderBase.h b/lib/al/include/Library/Scene/GameDataHolderBase.h
index be610fad..5d567723 100644
--- a/lib/al/include/Library/Scene/GameDataHolderBase.h
+++ b/lib/al/include/Library/Scene/GameDataHolderBase.h
@@ -5,5 +5,5 @@
 #include "Library/Scene/ISceneObj.h"
 
 namespace al {
-class GameDataHolderBase : public ISceneObj, HioNode, IUseMessageSystem {};
+class GameDataHolderBase : public ISceneObj, public HioNode, public IUseMessageSystem {};
 }  // namespace al
diff --git a/lib/al/include/Library/Screen/ScreenFunction.h b/lib/al/include/Library/Screen/ScreenFunction.h
index fdbe498f..52d99564 100644
--- a/lib/al/include/Library/Screen/ScreenFunction.h
+++ b/lib/al/include/Library/Screen/ScreenFunction.h
@@ -15,7 +15,7 @@ namespace al {
 class SceneCameraInfo;
 class ScreenCapture;
 
-class ScreenCaptureExecutor : IUseHioNode {
+class ScreenCaptureExecutor : public IUseHioNode {
 public:
     ScreenCaptureExecutor(s32);
     ~ScreenCaptureExecutor();
diff --git a/src/Layout/StageSceneLayout.h b/src/Layout/StageSceneLayout.h
index 53edd603..183663b3 100644
--- a/src/Layout/StageSceneLayout.h
+++ b/src/Layout/StageSceneLayout.h
@@ -17,7 +17,7 @@ class PlayGuideCamera;
 class PlayGuideBgm;
 class MapMini;
 
-class StageSceneLayout : al::NerveStateBase {
+class StageSceneLayout : public al::NerveStateBase {
 public:
     StageSceneLayout(const char*, const al::LayoutInitInfo&, const al::PlayerHolder*,
                      const al::SubCameraRenderer*);
diff --git a/src/MapObj/WorldMapEarth.h b/src/MapObj/WorldMapEarth.h
index 63ec205b..8b050906 100644
--- a/src/MapObj/WorldMapEarth.h
+++ b/src/MapObj/WorldMapEarth.h
@@ -2,7 +2,7 @@
 
 #include "Library/LiveActor/LiveActor.h"
 
-class WorldMapEarth : al::LiveActor {
+class WorldMapEarth : public al::LiveActor {
 public:
     WorldMapEarth(const char* name);
     void init(const al::ActorInitInfo& initInfo) override;
diff --git a/src/Player/PlayerConst.h b/src/Player/PlayerConst.h
index 71b34b3c..ed1d0f03 100644
--- a/src/Player/PlayerConst.h
+++ b/src/Player/PlayerConst.h
@@ -3,7 +3,7 @@
 #include "Library/HostIO/HioNode.h"
 #include "Library/Yaml/ByamlIter.h"
 
-class PlayerConst : al::HioNode {
+class PlayerConst : public al::HioNode {
 public:
     PlayerConst();
     PlayerConst(const al::ByamlIter&);
diff --git a/src/Player/PlayerModelChangerHakoniwa.h b/src/Player/PlayerModelChangerHakoniwa.h
index 195825b1..9f954a14 100644
--- a/src/Player/PlayerModelChangerHakoniwa.h
+++ b/src/Player/PlayerModelChangerHakoniwa.h
@@ -12,7 +12,7 @@ class PlayerPainPartsKeeper;
 class PlayerCostumeInfo;
 class IUseDimension;
 
-class PlayerModelChangerHakoniwa : IPlayerModelChanger, al::HioNode {
+class PlayerModelChangerHakoniwa : public IPlayerModelChanger, public al::HioNode {
 public:
     PlayerModelChangerHakoniwa(const al::LiveActor*, PlayerModelHolder*, PlayerPainPartsKeeper*,
                                PlayerCostumeInfo*, const IUseDimension*);
diff --git a/tools/check-format.py b/tools/check-format.py
index 91fdb8d0..75e1fe5c 100755
--- a/tools/check-format.py
+++ b/tools/check-format.py
@@ -192,11 +192,12 @@ def header_sorted_visibility(c, path):
         if line.endswith("\\"): line = line[0:-1]
         line = line.strip()
         if line not in visibilities_ordered:
-            header_check_line(line, path, nest_level[-1])
+            header_check_line(line, path, nest_level[-1], should_start_class)
         if "{" in line and "}" in line:
             if CHECK(lambda a:a.count("{")==a.count("}") or (a.startswith("{") and a.endswith("}};")), line, "Unbalanced \"{\" and \"}\" in the same line! (exception: end of brace-initialized array)", path): return
             if line.startswith("{") and line.endswith("}};"):
                 del nest_level[-1]
+            should_start_class = False
             continue
         
         if line.startswith("class ") and not line.endswith(";"):
@@ -221,9 +222,22 @@ def header_sorted_visibility(c, path):
         print("nest_level", nest_level)
         exit(1)
  
-def header_check_line(line, path, visibility):
+def header_check_line(line, path, visibility, should_start_class):
     if visibility == -2:  # outside of class/struct/...
-        pass
+        if (line.startswith("class") and (not line.endswith(";") or "{" in line)) or should_start_class:
+            if ": " in line and not ": public" in line and not ": virtual public" in line:
+                FAIL("All superclasses must be public!", line, path)
+            if should_start_class and not ": " in line and not line.startswith("public") and not line.startswith("virtual public"):
+                FAIL("All superclasses must be public!", line, path)
+            
+            if line.startswith("class") and "{" in line and ": " in line:
+                index = 0
+                while index < len(line):
+                    index = line.find(",", index+1)
+                    if index == -1: break
+                    if index < line.find(": "): continue
+                    if index != line.find(", public", index) and index != line.find(", virtual public", index):
+                        FAIL("All superclasses must be public!", line, path)
     elif visibility == -1:  # inside class, but not in a visibility block
         allowed = line in ["", "};"] or line.startswith("SEAD_SINGLETON_DISPOSER") or line.startswith("SEAD_RTTI_BASE") or line.startswith("SEAD_RTTI_OVERRIDE")
         CHECK(lambda a:allowed, line, "Inside class, but not in a visibility block, only empty lines and closing brace allowed!", path)