diff --git a/app/Http/Controllers/Apis/Protected/Summit/OAuth2SummitEventsApiController.php b/app/Http/Controllers/Apis/Protected/Summit/OAuth2SummitEventsApiController.php
index 0d8cbea9..c11fe549 100644
--- a/app/Http/Controllers/Apis/Protected/Summit/OAuth2SummitEventsApiController.php
+++ b/app/Http/Controllers/Apis/Protected/Summit/OAuth2SummitEventsApiController.php
@@ -346,19 +346,18 @@ final class OAuth2SummitEventsApiController extends OAuth2ProtectedController
             if(!Request::isJson()) return $this->error403();
             $data = Input::json();
 
-            $rules = array
-            (
+            $rules = [
                 'title'           => 'sometimes|required|string|max:100',
-                'description'     => 'sometimes|required|string',
+                'description'     => 'sometimes|string',
                 'social_summary'  => 'sometimes|string|max:100',
-                'location_id'     => 'sometimes|required|integer',
-                'start_date'      => 'sometimes|required|date_format:U',
+                'location_id'     => 'sometimes|integer',
+                'start_date'      => 'sometimes|date_format:U',
                 'end_date'        => 'sometimes|required_with:start_date|date_format:U|after:start_date',
-                'allow_feedback'  => 'sometimes|required|boolean',
+                'allow_feedback'  => 'sometimes|boolean',
                 'type_id'         => 'sometimes|required|integer',
                 'track_id'        => 'sometimes|required|integer',
-                'tags'            => 'sometimes|required|string_array',
-            );
+                'tags'            => 'sometimes|string_array',
+            ];
 
             // Creates a Validator instance and validates the data.
             $validation = Validator::make($data->all(), $rules);
@@ -372,12 +371,11 @@ final class OAuth2SummitEventsApiController extends OAuth2ProtectedController
                 );
             }
 
-            $fields = array
-            (
+            $fields = [
                 'title',
                 'description',
                 'social_summary',
-            );
+            ];
 
             $event = $this->service->updateEvent($summit, $event_id, HTMLCleaner::cleanData($data->all(), $fields));
 
diff --git a/app/Models/Foundation/Summit/Events/SummitEvent.php b/app/Models/Foundation/Summit/Events/SummitEvent.php
index 254c57b3..86a490b5 100644
--- a/app/Models/Foundation/Summit/Events/SummitEvent.php
+++ b/app/Models/Foundation/Summit/Events/SummitEvent.php
@@ -541,6 +541,11 @@ class SummitEvent extends SilverstripeBaseModel
         return $this;
     }
 
+    public function clearLocation(){
+        $this->location = null;
+        return $this;
+    }
+
     /**
      * @return SummitAbstractLocation
      */
diff --git a/app/Services/Model/SummitService.php b/app/Services/Model/SummitService.php
index 71f7ffbc..ebc56b8e 100644
--- a/app/Services/Model/SummitService.php
+++ b/app/Services/Model/SummitService.php
@@ -593,7 +593,7 @@ final class SummitService implements ISummitService
             $location = null;
             if (isset($data['location_id'])) {
                 $location = $summit->getLocation(intval($data['location_id']));
-                if (is_null($location)) {
+                if (is_null($location) && intval($data['location_id']) > 0) {
                     throw new EntityNotFoundException(sprintf("location id %s does not exists!", $data['location_id']));
                 }
             }
@@ -619,7 +619,7 @@ final class SummitService implements ISummitService
                 $event->setRsvpLink(html_entity_decode(trim($data['rsvp_link'])));
 
             if (isset($data['head_count']))
-                $event->setHeadCount(intval(data['head_count']));
+                $event->setHeadCount(intval($data['head_count']));
 
             if (isset($data['social_summary']))
                 $event->setSocialSummary(strip_tags(trim($data['social_summary'])));
@@ -641,13 +641,17 @@ final class SummitService implements ISummitService
             }
 
             $event->setSummit($summit);
-
-            if (!is_null($location))
+            if(!is_null($location))
                 $event->setLocation($location);
 
+            if(is_null($location) && isset($data['location_id'])){
+                // clear location
+                $event->clearLocation();
+            }
+
             $this->updateEventDates($data, $summit, $event);
 
-            if (isset($data['tags']) && count($data['tags']) > 0) {
+            if (isset($data['tags'])) {
                 $event->clearTags();
                 foreach ($data['tags'] as $str_tag) {
                     $tag = $this->tag_repository->getByTag($str_tag);
@@ -665,7 +669,7 @@ final class SummitService implements ISummitService
                 throw new ValidationException('sponsors are mandatory!');
             }
 
-            if (count($sponsors) > 0) {
+            if (isset($data['sponsors'])) {
                 $event->clearSponsors();
                 foreach ($sponsors as $sponsor_id) {
                     $sponsor = $this->company_repository->getById(intval($sponsor_id));
diff --git a/tests/OAuth2SummitApiTest.php b/tests/OAuth2SummitApiTest.php
index eb7e1585..8e0cccd5 100644
--- a/tests/OAuth2SummitApiTest.php
+++ b/tests/OAuth2SummitApiTest.php
@@ -2444,7 +2444,12 @@ final class OAuth2SummitApiTest extends ProtectedApiTest
         $params = [
 
             'id' => 23,
-            'filter' => ['selection_status==lightning-alternate', 'event_type_id==117'],
+            'filter' =>
+                [
+                    'selection_status==lightning-alternate',
+                    'event_type_id==117',
+                    'title=@test,abstract=@test,social_summary=@test,tags=@test,speaker=@test'
+                ],
             'expand' => 'speakers',
         ];