diff --git a/backend/README.md b/backend/README.md
index bcf1dec..2ca1217 100644
--- a/backend/README.md
+++ b/backend/README.md
@@ -29,6 +29,10 @@ To run celery queue processing:
 
     celery worker -A appenlight.celery -Q "reports,logs,metrics,default" --ini=development.ini
 
+To run celery beats scheduling:
+
+    celery beat -A appenlight.celery --ini=development.ini
+
 You should also run the channelstream websocket server for real-time notifications
 
     channelstream -i filename.ini
diff --git a/backend/src/appenlight/lib/rule.py b/backend/src/appenlight/lib/rule.py
index b7d4fd5..a0c99e8 100644
--- a/backend/src/appenlight/lib/rule.py
+++ b/backend/src/appenlight/lib/rule.py
@@ -188,6 +188,10 @@ class Rule(RuleBase):
             rule = OR(self.config['rules'], self.type_matrix,
                       config_manipulator=self.config_manipulator)
             return rule.match(struct)
+        elif field_name == '__NOT__':
+            rule = NOT(self.config['rules'], self.type_matrix,
+                      config_manipulator=self.config_manipulator)
+            return rule.match(struct)
 
         if test_value is None:
             return False
@@ -236,6 +240,16 @@ class AND(Rule):
                     in self.rules])
 
 
+class NOT(Rule):
+    def __init__(self, rules, *args, **kwargs):
+        super(NOT, self).__init__({}, *args, **kwargs)
+        self.rules = rules
+
+    def match(self, struct):
+        return all([not self.subrule_check(r_conf, struct) for r_conf
+                    in self.rules])
+
+
 class OR(Rule):
     def __init__(self, rules, *args, **kwargs):
         super(OR, self).__init__({}, *args, **kwargs)
@@ -266,7 +280,8 @@ class RuleService(object):
         if manipulator_func is None:
             def label_rewriter_func(rule):
                 field = rule.config.get('field')
-                if not field or rule.config['field'] in ['__OR__', '__AND__']:
+                if not field or rule.config['field'] in ['__OR__',
+                                                         '__AND__', '__NOT__']:
                     return
 
                 to_map = field_mappings.get(rule.config['field'])
diff --git a/backend/src/appenlight/static/js/appenlight.js b/backend/src/appenlight/static/js/appenlight.js
index d457b1c..16081e4 100644
--- a/backend/src/appenlight/static/js/appenlight.js
+++ b/backend/src/appenlight/static/js/appenlight.js
@@ -5376,11 +5376,11 @@ function kickstartAE() {
     "        {{rule_ctrlr.readOnlyPossibleFields[rule_ctrlr.rule.field]}}\n" +
     "    </span>\n" +
     "\n" +
-    "    <span ng-if=\"rule_ctrlr.rule.field != '__AND__' && rule_ctrlr.rule.field !='__OR__'\">\n" +
+    "    <span ng-if=\"rule_ctrlr.rule.field != '__AND__' && rule_ctrlr.rule.field !='__OR__' && rule_ctrlr.rule.field !='__NOT__'\">\n" +
     "          is {{rule_ctrlr.ruleDefinitions.allOps[rule_ctrlr.rule.op]}}  {{rule_ctrlr.rule.value}}\n" +
     "    </span>\n" +
     "\n" +
-    "    <span ng-if=\"rule_ctrlr.rule.field == '__AND__' || rule_ctrlr.rule.field =='__OR__'\">\n" +
+    "    <span ng-if=\"rule_ctrlr.rule.field == '__AND__' || rule_ctrlr.rule.field =='__OR__' || rule_ctrlr.rule.field =='__NOT__'\">\n" +
     "        <p ng-if=\"parent\"><strong>Subrules</strong></p>\n" +
     "        <div ng-repeat=\"subrule in rule_ctrlr.rule.rules\" class=\"m-l-2\">\n" +
     "\n" +
@@ -5408,7 +5408,7 @@ function kickstartAE() {
     "                ng-options=\"key as label for (key, label) in rule_ctrlr.ruleDefinitions.possibleFields\"></select>\n" +
     "    </div>\n" +
     "\n" +
-    "    <div ng-if=\"rule_ctrlr.rule.field != '__AND__' && rule_ctrlr.rule.field !='__OR__'\" class=\"form-group\">\n" +
+    "    <div ng-if=\"rule_ctrlr.rule.field != '__AND__' && rule_ctrlr.rule.field !='__OR__' && rule_ctrlr.rule.field !='__NOT__'\" class=\"form-group\">\n" +
     "\n" +
     "            <select ng-model=\"rule_ctrlr.rule.op\" class=\"form-control\"\n" +
     "                    ng-change=\"rule_ctrlr.setDirty()\"\n" +
@@ -5419,7 +5419,7 @@ function kickstartAE() {
     "\n" +
     "    </div>\n" +
     "\n" +
-    "    <span ng-if=\"rule_ctrlr.rule.field == '__AND__' || rule_ctrlr.rule.field =='__OR__'\">\n" +
+    "    <span ng-if=\"rule_ctrlr.rule.field == '__AND__' || rule_ctrlr.rule.field =='__OR__' || rule_ctrlr.rule.field =='__NOT__'\">\n" +
     "        <p ng-if=\"parent\"><strong>Subrules</strong></p>\n" +
     "        <div ng-repeat=\"subrule in rule_ctrlr.rule.rules\" class=\"m-l-2\">\n" +
     "            <div class=\"panel panel-default\">\n" +
@@ -10694,6 +10694,7 @@ function AlertChannelsController(userSelfPropertyResource, applicationsNoIdResou
     var possibleFields = {
         '__AND__': 'All met (composite rule)',
         '__OR__': 'One met (composite rule)',
+        '__NOT__': 'Not met (composite rule)',
         'http_status': 'HTTP Status',
         'duration': 'Request duration',
         'group:priority': 'Group -> Priority',
@@ -11610,6 +11611,7 @@ angular.module('appenlight.directives.postProcessAction', []).directive('postPro
         var possibleFields = {
             '__AND__': 'All met (composite rule)',
             '__OR__': 'One met (composite rule)',
+            '__NOT__': 'Not met (composite rule)',
             'http_status': 'HTTP Status',
             'duration': 'Request duration',
             'group:priority': 'Group -> Priority',
@@ -11927,8 +11929,9 @@ angular.module('appenlight.directives.rule', []).directive('rule', function () {
         };
 
         vm.fieldChange = function () {
-            var new_is_compound = ['__AND__', '__OR__'].indexOf(vm.rule.field) !== -1;
-            var old_was_compound = ['__AND__', '__OR__'].indexOf(vm.oldField) !== -1;
+            var compound_types = ['__AND__', '__OR__', '__NOT__'];
+            var new_is_compound = compound_types.indexOf(vm.rule.field) !== -1;
+            var old_was_compound = compound_types.indexOf(vm.oldField) !== -1;
 
             if (!new_is_compound) {
                 vm.rule.op = vm.ruleDefinitions.fieldOps[vm.rule.field][0];
diff --git a/backend/src/appenlight/tests/test_unit.py b/backend/src/appenlight/tests/test_unit.py
index bd09688..025d52b 100644
--- a/backend/src/appenlight/tests/test_unit.py
+++ b/backend/src/appenlight/tests/test_unit.py
@@ -1031,6 +1031,38 @@ class TestRulesParsing():
 
 @pytest.mark.usefixtures('report_type_matrix')
 class TestNestedRuleParsing():
+
+    @pytest.mark.parametrize("data, result", [
+        ({"http_status": 501, "group": {"priority": 7, "occurences": 11}},
+         False),
+        ({"http_status": 101, "group": {"priority": 7, "occurences": 11}},
+         False),
+        ({"http_status": 500, "group": {"priority": 1, "occurences": 11}},
+         False),
+        ({"http_status": 101, "group": {"priority": 3, "occurences": 5}},
+         True),
+    ])
+    def test_NOT_rule(self, data, result, report_type_matrix):
+        from appenlight.lib.rule import Rule
+        rule_config = {
+            "field": "__NOT__",
+            "rules": [
+                {
+                    "op": "ge",
+                    "field": "group:occurences",
+                    "value": "10"
+                },
+                {
+                    "op": "ge",
+                    "field": "group:priority",
+                    "value": "4"
+                }
+            ]
+        }
+
+        rule = Rule(rule_config, report_type_matrix)
+        assert rule.match(data) is result
+
     @pytest.mark.parametrize("data, result", [
         ({"http_status": 501, "group": {"priority": 7, "occurences": 11}},
          True),
diff --git a/backend/src/appenlight/validators.py b/backend/src/appenlight/validators.py
index 636dc1a..f5cfe32 100644
--- a/backend/src/appenlight/validators.py
+++ b/backend/src/appenlight/validators.py
@@ -716,7 +716,7 @@ def build_rule_schema(ruleset, check_matrix):
     schema = colander.SchemaNode(colander.Mapping())
     schema.add(colander.SchemaNode(colander.String(), name='field'))
 
-    if ruleset['field'] in ['__AND__', '__OR__']:
+    if ruleset['field'] in ['__AND__', '__OR__', '__NOT__']:
         subrules = colander.SchemaNode(colander.Tuple(), name='rules')
         for rule in ruleset['rules']:
             subrules.add(build_rule_schema(rule, check_matrix))
diff --git a/frontend/src/controllers/user/alert_channels.js b/frontend/src/controllers/user/alert_channels.js
index 2aa18d5..1507d97 100644
--- a/frontend/src/controllers/user/alert_channels.js
+++ b/frontend/src/controllers/user/alert_channels.js
@@ -70,6 +70,7 @@ function AlertChannelsController(userSelfPropertyResource, applicationsNoIdResou
     var possibleFields = {
         '__AND__': 'All met (composite rule)',
         '__OR__': 'One met (composite rule)',
+        '__NOT__': 'Not met (composite rule)',
         'http_status': 'HTTP Status',
         'duration': 'Request duration',
         'group:priority': 'Group -> Priority',
diff --git a/frontend/src/directives/postprocess_action.js b/frontend/src/directives/postprocess_action.js
index 70d4020..92bd1ea 100644
--- a/frontend/src/directives/postprocess_action.js
+++ b/frontend/src/directives/postprocess_action.js
@@ -61,6 +61,7 @@ angular.module('appenlight.directives.postProcessAction', []).directive('postPro
         var possibleFields = {
             '__AND__': 'All met (composite rule)',
             '__OR__': 'One met (composite rule)',
+            '__NOT__': 'Not met (composite rule)',
             'http_status': 'HTTP Status',
             'duration': 'Request duration',
             'group:priority': 'Group -> Priority',
diff --git a/frontend/src/directives/rule.js b/frontend/src/directives/rule.js
index 4c08578..bd9a8fb 100644
--- a/frontend/src/directives/rule.js
+++ b/frontend/src/directives/rule.js
@@ -56,8 +56,9 @@ angular.module('appenlight.directives.rule', []).directive('rule', function () {
         };
 
         vm.fieldChange = function () {
-            var new_is_compound = ['__AND__', '__OR__'].indexOf(vm.rule.field) !== -1;
-            var old_was_compound = ['__AND__', '__OR__'].indexOf(vm.oldField) !== -1;
+            var compound_types = ['__AND__', '__OR__', '__NOT__'];
+            var new_is_compound = compound_types.indexOf(vm.rule.field) !== -1;
+            var old_was_compound = compound_types.indexOf(vm.oldField) !== -1;
 
             if (!new_is_compound) {
                 vm.rule.op = vm.ruleDefinitions.fieldOps[vm.rule.field][0];
diff --git a/frontend/src/templates/directives/rule.html b/frontend/src/templates/directives/rule.html
index e3a8a7d..4faaa9b 100644
--- a/frontend/src/templates/directives/rule.html
+++ b/frontend/src/templates/directives/rule.html
@@ -7,7 +7,7 @@
                 ng-options="key as label for (key, label) in rule_ctrlr.ruleDefinitions.possibleFields"></select>
     </div>
 
-    <div ng-if="rule_ctrlr.rule.field != '__AND__' && rule_ctrlr.rule.field !='__OR__'" class="form-group">
+    <div ng-if="rule_ctrlr.rule.field != '__AND__' && rule_ctrlr.rule.field !='__OR__' && rule_ctrlr.rule.field !='__NOT__'" class="form-group">
 
             <select ng-model="rule_ctrlr.rule.op" class="form-control"
                     ng-change="rule_ctrlr.setDirty()"
@@ -18,7 +18,7 @@
 
     </div>
 
-    <span ng-if="rule_ctrlr.rule.field == '__AND__' || rule_ctrlr.rule.field =='__OR__'">
+    <span ng-if="rule_ctrlr.rule.field == '__AND__' || rule_ctrlr.rule.field =='__OR__' || rule_ctrlr.rule.field =='__NOT__'">
         <p ng-if="parent"><strong>Subrules</strong></p>
         <div ng-repeat="subrule in rule_ctrlr.rule.rules" class="m-l-2">
             <div class="panel panel-default">
diff --git a/frontend/src/templates/directives/rule_read_only.html b/frontend/src/templates/directives/rule_read_only.html
index 205e88b..20c98e0 100644
--- a/frontend/src/templates/directives/rule_read_only.html
+++ b/frontend/src/templates/directives/rule_read_only.html
@@ -4,11 +4,11 @@
         {{rule_ctrlr.readOnlyPossibleFields[rule_ctrlr.rule.field]}}
     </span>
 
-    <span ng-if="rule_ctrlr.rule.field != '__AND__' && rule_ctrlr.rule.field !='__OR__'">
+    <span ng-if="rule_ctrlr.rule.field != '__AND__' && rule_ctrlr.rule.field !='__OR__' && rule_ctrlr.rule.field !='__NOT__'">
           is {{rule_ctrlr.ruleDefinitions.allOps[rule_ctrlr.rule.op]}}  {{rule_ctrlr.rule.value}}
     </span>
 
-    <span ng-if="rule_ctrlr.rule.field == '__AND__' || rule_ctrlr.rule.field =='__OR__'">
+    <span ng-if="rule_ctrlr.rule.field == '__AND__' || rule_ctrlr.rule.field =='__OR__' || rule_ctrlr.rule.field =='__NOT__'">
         <p ng-if="parent"><strong>Subrules</strong></p>
         <div ng-repeat="subrule in rule_ctrlr.rule.rules" class="m-l-2">