diff --git a/osu.Game.Rulesets.Mania/ManiaFilterCriteria.cs b/osu.Game.Rulesets.Mania/ManiaFilterCriteria.cs
index 58aef4dbf8..c8832dfdfb 100644
--- a/osu.Game.Rulesets.Mania/ManiaFilterCriteria.cs
+++ b/osu.Game.Rulesets.Mania/ManiaFilterCriteria.cs
@@ -1,8 +1,6 @@
 // Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
 // See the LICENCE file in the repository root for full licence text.
 
-#nullable disable
-
 using osu.Game.Beatmaps;
 using osu.Game.Rulesets.Filter;
 using osu.Game.Rulesets.Mania.Beatmaps;
diff --git a/osu.Game.Tests/NonVisual/Filtering/FilterMatchingTest.cs b/osu.Game.Tests/NonVisual/Filtering/FilterMatchingTest.cs
index 2657468b03..33204d33a7 100644
--- a/osu.Game.Tests/NonVisual/Filtering/FilterMatchingTest.cs
+++ b/osu.Game.Tests/NonVisual/Filtering/FilterMatchingTest.cs
@@ -1,8 +1,6 @@
 // Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
 // See the LICENCE file in the repository root for full licence text.
 
-#nullable disable
-
 using NUnit.Framework;
 using osu.Game.Beatmaps;
 using osu.Game.Rulesets;
diff --git a/osu.Game.Tests/NonVisual/Filtering/FilterQueryParserTest.cs b/osu.Game.Tests/NonVisual/Filtering/FilterQueryParserTest.cs
index 500f3159e2..bd0617515b 100644
--- a/osu.Game.Tests/NonVisual/Filtering/FilterQueryParserTest.cs
+++ b/osu.Game.Tests/NonVisual/Filtering/FilterQueryParserTest.cs
@@ -1,8 +1,6 @@
 // Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
 // See the LICENCE file in the repository root for full licence text.
 
-#nullable disable
-
 using System;
 using NUnit.Framework;
 using osu.Game.Beatmaps;
@@ -256,7 +254,7 @@ namespace osu.Game.Tests.NonVisual.Filtering
 
         private class CustomFilterCriteria : IRulesetFilterCriteria
         {
-            public string CustomValue { get; set; }
+            public string? CustomValue { get; set; }
 
             public bool Matches(BeatmapInfo beatmapInfo) => true;
 
diff --git a/osu.Game/Rulesets/Filter/IRulesetFilterCriteria.cs b/osu.Game/Rulesets/Filter/IRulesetFilterCriteria.cs
index fa44f81df3..dd2ad2cbfa 100644
--- a/osu.Game/Rulesets/Filter/IRulesetFilterCriteria.cs
+++ b/osu.Game/Rulesets/Filter/IRulesetFilterCriteria.cs
@@ -1,8 +1,6 @@
 // Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
 // See the LICENCE file in the repository root for full licence text.
 
-#nullable disable
-
 using osu.Game.Beatmaps;
 using osu.Game.Screens.Select;
 using osu.Game.Screens.Select.Filter;