diff --git a/tests/php/ReadingModeTest.php b/tests/php/ReadingModeTest.php
index 4861a261..3b28867a 100644
--- a/tests/php/ReadingModeTest.php
+++ b/tests/php/ReadingModeTest.php
@@ -88,7 +88,7 @@ public function testFromQueryString($readingMode, $dataQuery, $queryStringArray,
      *  - query string (string)
      * @return array
      */
-    public function provideReadingModes()
+    public static function provideReadingModes()
     {
         return [
             // Draft
@@ -156,7 +156,7 @@ public function testInvalidStage($stage)
         ReadingMode::validateStage($stage);
     }
 
-    public function provideTestInvalidStage()
+    public static function provideTestInvalidStage()
     {
         return [
             [''],
diff --git a/tests/php/RecursiveStagesServiceTest.php b/tests/php/RecursiveStagesServiceTest.php
index 6458ce8f..2a7a7740 100644
--- a/tests/php/RecursiveStagesServiceTest.php
+++ b/tests/php/RecursiveStagesServiceTest.php
@@ -81,7 +81,7 @@ public function testStageDiffersRecursive(string $class, string $identifier, boo
         });
     }
 
-    public function objectsProvider(): array
+    public static function objectsProvider(): array
     {
         return [
             'primary object (versioned, update)' => [
diff --git a/tests/php/VersionedNumberCacheTest.php b/tests/php/VersionedNumberCacheTest.php
index 213856e3..36453e15 100644
--- a/tests/php/VersionedNumberCacheTest.php
+++ b/tests/php/VersionedNumberCacheTest.php
@@ -68,7 +68,7 @@ protected function setUp(): void
         TestObject::singleton()->flushCache();
     }
 
-    public function cacheDataProvider()
+    public static function cacheDataProvider()
     {
         return [
             [Versioned::DRAFT, 'publishedID', false, 'draftVersion'],