diff --git a/apps/permission/backends.py b/apps/permission/backends.py
index ec136e9e..07e132f5 100644
--- a/apps/permission/backends.py
+++ b/apps/permission/backends.py
@@ -21,7 +21,7 @@ class PermissionBackend(ModelBackend):
     Manage permissions of users
     """
     supports_object_permissions = True
-    supports_anonymous_user = False
+    supports_anonymous_user = True
     supports_inactive_user = False
 
     @staticmethod
@@ -33,24 +33,18 @@ class PermissionBackend(ModelBackend):
         :param t: The type of the permissions: view, change, add or delete
         :return: The queryset of the permissions of the user (memoized) grouped by clubs
         """
-        if hasattr(request, 'auth') and request.auth is not None and hasattr(request.auth, 'scope'):
+        if hasattr(request, 'oauth2') and request.oauth2 is not None and 'scope' in request.oauth2:
             # OAuth2 Authentication
-            user = request.auth.user
+            user = request.oauth2['user']
 
             def permission_filter(membership_obj):
                 query = Q(pk=-1)
-                if 'mask' in request.GET:
-                    try:
-                        rank = int(request.GET['mask'])
-                    except ValueError:
-                        rank = 42
-                    query &= Q(mask__rank__lte=rank)
-                for scope in request.auth.scope.split(' '):
+                for scope in request.oauth2['scope']:
                     if scope == "openid":
                         continue
                     permission_id, club_id = scope.split('_')
                     if int(club_id) == membership_obj.club_id:
-                        query |= Q(pk=permission_id)
+                        query |= Q(pk=permission_id, mask__rank__lte=request.oauth2['mask'])
                 return query
         else:
             user = request.user
diff --git a/apps/permission/scopes.py b/apps/permission/scopes.py
index 93b7a88b..47c72a67 100644
--- a/apps/permission/scopes.py
+++ b/apps/permission/scopes.py
@@ -25,7 +25,9 @@ class PermissionScopes(BaseScopes):
         if 'scopes' in kwargs:
             for scope in kwargs['scopes']:
                 if scope == 'openid':
-                    scopes['openid'] = "OpenID Connect"
+                    scopes['openid'] = _("OpenID Connect (username and email)")
+                elif scope == '0_0':
+                    scopes['0_0'] = _("Useless scope which do nothing")
                 else:
                     p = Permission.objects.get(id=scope.split('_')[0])
                     club = Club.objects.get(id=scope.split('_')[1])
@@ -35,6 +37,7 @@ class PermissionScopes(BaseScopes):
         scopes = {f"{p.id}_{club.id}": f"{p.description} (club {club.name})"
                   for p in Permission.objects.all() for club in Club.objects.all()}
         scopes['openid'] = _("OpenID Connect (username and email)")
+        scopes['0_0'] = _("Useless scope which do nothing")
         return scopes
 
     def get_available_scopes(self, application=None, request=None, *args, **kwargs):
@@ -43,7 +46,7 @@ class PermissionScopes(BaseScopes):
         scopes = [f"{p.id}_{p.membership.club.id}"
                   for t in Permission.PERMISSION_TYPES
                   for p in PermissionBackend.get_raw_permissions(get_current_request(), t[0])]
-        scopes.append('openid')
+        scopes.append('0_0')  # always available
         return scopes
 
     def get_default_scopes(self, application=None, request=None, *args, **kwargs):
@@ -51,7 +54,7 @@ class PermissionScopes(BaseScopes):
             return []
         scopes = [f"{p.id}_{p.membership.club.id}"
                   for p in PermissionBackend.get_raw_permissions(get_current_request(), 'view')]
-        scopes.append('openid')
+        scopes.append('0_0')
         return scopes
 
 
@@ -73,6 +76,37 @@ class PermissionOAuth2Validator(OAuth2Validator):
         claims = super().get_discovery_claims(self)
         return claims + ["name", "normalized_name", "email"]
 
+    def validate_client_credentials_scopes(self, client_id, scopes, client, request, *args, **kwargs):
+        """
+        For client credentials valid scopes are scope of the app owner
+        """
+        valid_scopes = set()
+        request.oauth2 = {}
+        request.oauth2['user'] = client.user
+        request.oauth2['user'].is_anomymous = False
+        request.oauth2['scope'] = scopes
+        # mask implementation
+        if hasattr(request.decoded_body, 'mask'):
+            try:
+                request.oauth2['mask'] = int(request.decoded_body['mask'])
+            except ValueError:
+                request.oauth2['mask'] = 42
+        else:
+            request.oauth2['mask'] = 42
+
+        for t in Permission.PERMISSION_TYPES:
+            for p in PermissionBackend.get_raw_permissions(request, t[0]):
+                scope = f"{p.id}_{p.membership.club.id}"
+                if scope in scopes:
+                    valid_scopes.add(scope)
+
+        # Always give one scope to generate token
+        if not valid_scopes:
+            valid_scopes.add('0_0')
+
+        request.scopes = valid_scopes
+        return valid_scopes
+
     def validate_scopes(self, client_id, scopes, client, request, *args, **kwargs):
         """
         User can request as many scope as he wants, including invalid scopes,
@@ -84,6 +118,9 @@ class PermissionOAuth2Validator(OAuth2Validator):
 
         valid_scopes = set()
 
+        if hasattr(request, 'grant_type') and request.grant_type == 'client_credentials':
+            return self.validate_client_credentials_scopes(client_id, scopes, client, request, args, kwargs)
+
         # simple patch for have functionnal ROPB flow
         # TODO rewrite
         r = get_current_request()
@@ -94,8 +131,8 @@ class PermissionOAuth2Validator(OAuth2Validator):
                 if scope in scopes:
                     valid_scopes.add(scope)
 
-        if 'openid' in scopes:
-            valid_scopes.add('openid')
+        if '0_0' in scopes:
+            valid_scopes.add('0_0')
 
         request.scopes = valid_scopes
         return valid_scopes
diff --git a/apps/permission/tests/test_oauth2_access.py b/apps/permission/tests/test_oauth2_access.py
index ebbbc7d7..f79d8866 100644
--- a/apps/permission/tests/test_oauth2_access.py
+++ b/apps/permission/tests/test_oauth2_access.py
@@ -126,6 +126,7 @@ class OAuth2TestCase(TestCase):
                                **{'Authorization': f'Bearer {token.token}'})
 
         # Token is not granted to see other api
-        resp = self.client.get(f'/api/user/{self.user.pk}/',
+        resp = self.client.get(f'/api/members/profile/{self.user.profile.pk}/',
                                **{'Authorization': f'Bearer {token.token}'})
+
         self.assertEqual(resp.status_code, 404)
diff --git a/apps/permission/tests/test_oauth2_flow.py b/apps/permission/tests/test_oauth2_flow.py
index 685da780..697803d1 100644
--- a/apps/permission/tests/test_oauth2_flow.py
+++ b/apps/permission/tests/test_oauth2_flow.py
@@ -7,7 +7,7 @@ from django.contrib.auth.models import User
 from django.test import TestCase
 from member.models import Membership, Club
 from note.models import NoteUser
-from oauth2_provider.models import Application
+from oauth2_provider.models import Application, AccessToken
 
 from ..models import Role, Permission
 
@@ -81,14 +81,10 @@ class OAuth2TestCase(TestCase):
 
         self.assertEqual(resp.status_code, 200)
 
-        token = resp.json()['access_token']
+        token = AccessToken.objects.get(token=resp.json()['access_token'])
 
-        # Token is valid but has no right
-        resp = self.client.get('/api/user/{self.user.pk}',
-                               **{'Authorization': f'Bearer {token}'}
-                               )
-
-        self.assertEqual(resp.status_code, 403)
+        # Token do nothing, it should be have the useless scope
+        self.assertEqual(token.scope, '0_0')
 
         # RFC6749 4.4.2 allows use of scope in client credential flow
         resp = self.client.post('/o/token/',
@@ -100,13 +96,10 @@ class OAuth2TestCase(TestCase):
 
         self.assertEqual(resp.status_code, 200)
 
-        token = resp.json()['access_token']
+        token = AccessToken.objects.get(token=resp.json()['access_token'])
 
-        # Now app can see his creator
-        resp = self.client.post(f'/api/user/{self.user.pk}/',
-                                **{'Authorization': f'Bearer {token}'})
-
-        self.assertEqual(resp.status_code, 200)
+        # Token can have access, it shouldn't have the useless scope
+        self.assertEqual(token.scope, self.base_scope)
 
     def test_oidc_flow(self):
         """