diff --git a/src/main/java/org/ultramine/permission/IChangeablePermission.java b/src/main/java/org/ultramine/permission/IChangeablePermission.java
index 2b8bc5a..cad4c8c 100644
--- a/src/main/java/org/ultramine/permission/IChangeablePermission.java
+++ b/src/main/java/org/ultramine/permission/IChangeablePermission.java
@@ -2,7 +2,6 @@
 
 public interface IChangeablePermission extends IPermission
 {
-	public boolean isDirty();
 	public void subscribe(IDirtyListener listener);
 	public void unsubscribe(IDirtyListener listener);
 }
diff --git a/src/main/java/org/ultramine/permission/NegativePermission.java b/src/main/java/org/ultramine/permission/NegativePermission.java
index 054baae..5578f5d 100644
--- a/src/main/java/org/ultramine/permission/NegativePermission.java
+++ b/src/main/java/org/ultramine/permission/NegativePermission.java
@@ -45,12 +45,6 @@
 	}
 
 	@Override
-	public boolean isDirty()
-	{
-		return (getType() == ProxyType.CHANGEABLE) && dirty;
-	}
-
-	@Override
 	public void makeDirty()
 	{
 		dirty = true;
diff --git a/src/main/java/org/ultramine/permission/PermissionRepository.java b/src/main/java/org/ultramine/permission/PermissionRepository.java
index 6039894..dec7309 100644
--- a/src/main/java/org/ultramine/permission/PermissionRepository.java
+++ b/src/main/java/org/ultramine/permission/PermissionRepository.java
@@ -117,12 +117,6 @@
 		}
 
 		@Override
-		public boolean isDirty()
-		{
-			return (proxyType == ProxyType.CHANGEABLE) && ((IChangeablePermission)wrappedPermission).isDirty();
-		}
-
-		@Override
 		public void subscribe(IDirtyListener listener)
 		{
 			switch (proxyType)
diff --git a/src/test/groovy/org/ultramine/permission/NegativePermissionTest.groovy b/src/test/groovy/org/ultramine/permission/NegativePermissionTest.groovy
index 435ceaf..5b22420 100644
--- a/src/test/groovy/org/ultramine/permission/NegativePermissionTest.groovy
+++ b/src/test/groovy/org/ultramine/permission/NegativePermissionTest.groovy
@@ -31,21 +31,6 @@
         perm.getPermissions().check("test.key") == FALSE
     }
 
-    def "Test isDirty IPermission"() {
-        setup:
-        IPermission permission = Mock(IPermission) {
-            getPermissions() >> PermissionResolver.createForKey("test.key", 1)
-            isDirty() >> true
-        }
-
-        when: "Create new NegativePermission"
-        def perm = new NegativePermission(permission)
-
-        then: "It is not dirty"
-        !perm.isDirty()
-        0 * permission.isDirty()
-    }
-
     def "Test subscribe/unsubscribe IPermission"() {
         setup:
         IPermission permission = Mock(IPermission) {
@@ -87,21 +72,6 @@
         perm.getPermissions().check("test.key") == FALSE
     }
 
-    def "Test isDirty IChangeablePermission"() {
-        setup:
-        IPermission permission = Mock(IChangeablePermission) {
-            getPermissions() >> PermissionResolver.createForKey("test.key", 1)
-        }
-        def perm = new NegativePermission(permission)
-
-        when: "Wrapped permission dirty changes"
-        permission.isDirty() >>> [true, false]
-
-        then: "Negative permission dirty is not changing"
-        perm.isDirty()
-        perm.isDirty()
-    }
-
     def "Test subscribe/unsubscribe IChangeablePermission"() {
         setup:
         IPermission permission = Mock(IChangeablePermission) {
diff --git a/src/test/groovy/org/ultramine/permission/PermissionRepositoryTest.groovy b/src/test/groovy/org/ultramine/permission/PermissionRepositoryTest.groovy
index 1d93cc7..442a8f2 100644
--- a/src/test/groovy/org/ultramine/permission/PermissionRepositoryTest.groovy
+++ b/src/test/groovy/org/ultramine/permission/PermissionRepositoryTest.groovy
@@ -127,21 +127,6 @@
         0 * perm.subscribe(_)
     }
 
-    def "Test proxy isDirty"() {
-        setup:
-        def repository = new PermissionRepository()
-        repository.registerPermission(Mock(IPermission) { getKey() >> "s" })
-        repository.registerPermission(Mock(IChangeablePermission) { getKey() >> "c"; isDirty() >>> [true, false] })
-
-        expect: "DUMMY and SIMPLE proxies are not dirty"
-        !repository.getPermission("d").isDirty()
-        !repository.getPermission("s").isDirty()
-
-        and: "CHANGEABLE proxy dirty check delegated to wrapped permission"
-        repository.getPermission("c").isDirty()
-        !repository.getPermission("c").isDirty()
-    }
-
     def "Test negative key"() {
         setup:
         def repository = new PermissionRepository()