diff --git a/src/libraries/Common/src/System/HexConverter.cs b/src/libraries/Common/src/System/HexConverter.cs
index 51d4647bafa726..fbd5d789c77d82 100644
--- a/src/libraries/Common/src/System/HexConverter.cs
+++ b/src/libraries/Common/src/System/HexConverter.cs
@@ -76,9 +76,6 @@ public static void ToBytesBuffer(byte value, Span<byte> buffer, int startingInde
             buffer[startingIndex] = (byte)(packedResult >> 8);
         }
 
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-        [System.Security.SecuritySafeCriticalAttribute]
-#endif
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public static void ToCharsBuffer(byte value, Span<char> buffer, int startingIndex = 0, Casing casing = Casing.Upper)
         {
@@ -190,9 +187,6 @@ public static void EncodeToUtf16(ReadOnlySpan<byte> bytes, Span<char> chars, Cas
             }
         }
 
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-        [System.Security.SecuritySafeCriticalAttribute]
-#endif
         public static unsafe string ToString(ReadOnlySpan<byte> bytes, Casing casing = Casing.Upper)
         {
 #if NETFRAMEWORK || NETSTANDARD2_0
diff --git a/src/libraries/System.Diagnostics.DiagnosticSource/src/AssemblyInfo.netfx.cs b/src/libraries/System.Diagnostics.DiagnosticSource/src/AssemblyInfo.netfx.cs
deleted file mode 100644
index 114bc90eee7321..00000000000000
--- a/src/libraries/System.Diagnostics.DiagnosticSource/src/AssemblyInfo.netfx.cs
+++ /dev/null
@@ -1,6 +0,0 @@
-// Licensed to the .NET Foundation under one or more agreements.
-// The .NET Foundation licenses this file to you under the MIT license.
-
-using System.Security;
-
-[assembly: AllowPartiallyTrustedCallers]
diff --git a/src/libraries/System.Diagnostics.DiagnosticSource/src/System.Diagnostics.DiagnosticSource.csproj b/src/libraries/System.Diagnostics.DiagnosticSource/src/System.Diagnostics.DiagnosticSource.csproj
index 349a9d929d6705..db7ca3770e6326 100644
--- a/src/libraries/System.Diagnostics.DiagnosticSource/src/System.Diagnostics.DiagnosticSource.csproj
+++ b/src/libraries/System.Diagnostics.DiagnosticSource/src/System.Diagnostics.DiagnosticSource.csproj
@@ -16,7 +16,7 @@ System.Diagnostics.DiagnosticSource</PackageDescription>
 
   <!-- DesignTimeBuild requires all the TargetFramework Derived Properties to not be present in the first property group. -->
   <PropertyGroup>
-    <DefineConstants Condition="$([MSBuild]::GetTargetFrameworkIdentifier('$(TargetFramework)')) == '.NETFramework'">$(DefineConstants);ALLOW_PARTIALLY_TRUSTED_CALLERS;ENABLE_HTTP_HANDLER</DefineConstants>
+    <DefineConstants Condition="$([MSBuild]::GetTargetFrameworkIdentifier('$(TargetFramework)')) == '.NETFramework'">$(DefineConstants);ENABLE_HTTP_HANDLER</DefineConstants>
     <DefineConstants Condition="$([MSBuild]::GetTargetFrameworkIdentifier('$(TargetFramework)')) == '.NETCoreApp'">$(DefineConstants);W3C_DEFAULT_ID_FORMAT;MEMORYMARSHAL_SUPPORT;OS_ISBROWSER_SUPPORT</DefineConstants>
     <IncludePlatformAttributes>true</IncludePlatformAttributes>
   </PropertyGroup>
@@ -116,7 +116,6 @@ System.Diagnostics.DiagnosticSource</PackageDescription>
 
   <ItemGroup Condition="'$(TargetFrameworkIdentifier)' == '.NETFramework'">
     <Compile Include="System\Diagnostics\HttpHandlerDiagnosticListener.cs" />
-    <Compile Include="AssemblyInfo.netfx.cs" />
     <Compile Include="System\Diagnostics\Activity.DateTime.netfx.cs" />
   </ItemGroup>
 
diff --git a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Activity.cs b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Activity.cs
index f445dd255e1683..581d710fba4ae7 100644
--- a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Activity.cs
+++ b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Activity.cs
@@ -17,9 +17,6 @@ namespace System.Diagnostics
     /// <summary>
     /// Carries the <see cref="Activity.Current"/> changed event data.
     /// </summary>
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-    [System.Security.SecuritySafeCriticalAttribute]
-#endif
     public readonly struct ActivityChangedEventArgs
     {
         internal ActivityChangedEventArgs(Activity? previous, Activity? current)
@@ -219,9 +216,6 @@ public string DisplayName
         /// </example>
         public string? Id
         {
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-        [System.Security.SecuritySafeCriticalAttribute]
-#endif
             get
             {
                 // if we represented it as a traceId-spanId, convert it to a string.
@@ -250,9 +244,6 @@ public string? Id
         /// </summary>
         public string? ParentId
         {
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-            [System.Security.SecuritySafeCriticalAttribute]
-#endif
             get
             {
                 // if we represented it as a traceId-spanId, convert it to a string.
@@ -791,9 +782,6 @@ public string? TraceStateString
         /// </summary>
         public ActivitySpanId SpanId
         {
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-            [System.Security.SecuritySafeCriticalAttribute]
-#endif
             get
             {
                 if (_spanId is null)
@@ -863,9 +851,6 @@ public ActivityTraceFlags ActivityTraceFlags
         /// </summary>
         public ActivitySpanId ParentSpanId
         {
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-            [System.Security.SecuritySafeCriticalAttribute]
-#endif
             get
             {
                 if (_parentSpanId is null)
@@ -971,9 +956,6 @@ private static bool IsW3CId(string id)
                    (id[0] != 'f' || id[1] != 'f');
         }
 
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-        [System.Security.SecuritySafeCriticalAttribute]
-#endif
         internal static bool TryConvertIdToContext(string traceParent, string? traceState, bool isRemote, out ActivityContext context)
         {
             context = default;
@@ -1279,9 +1261,6 @@ private string AppendSuffix(string parentId, string suffix, char delimiter)
         }
 #pragma warning restore CA1822
 
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-        [System.Security.SecuritySafeCriticalAttribute]
-#endif
         private static unsafe long GetRandomNumber()
         {
             // Use the first 8 bytes of the GUID as a random number.
@@ -1300,9 +1279,6 @@ private static bool ValidateSetCurrent(Activity? activity)
             return canSet;
         }
 
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-        [System.Security.SecuritySafeCriticalAttribute]
-#endif
         private bool TrySetTraceIdFromParent()
         {
             Debug.Assert(_traceId is null);
@@ -1325,9 +1301,6 @@ private bool TrySetTraceIdFromParent()
             return _traceId != null;
         }
 
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-        [System.Security.SecuritySafeCriticalAttribute]
-#endif
         private void TrySetTraceFlagsFromParent()
         {
             Debug.Assert(!W3CIdFlagsSet);
@@ -1770,9 +1743,6 @@ public enum ActivityIdFormat
     /// it has to, and caches the string representation after it was created.
     /// It is mostly useful as an exchange type.
     /// </summary>
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-        [System.Security.SecuritySafeCriticalAttribute]
-#endif
     public readonly struct ActivityTraceId : IEquatable<ActivityTraceId>
     {
         private readonly string? _hexString;
@@ -1954,9 +1924,6 @@ internal static bool IsLowerCaseHexAndNotAllZeros(ReadOnlySpan<char> idData)
     /// it has to, and caches the string representation after it was created.
     /// It is mostly useful as an exchange type.
     /// </summary>
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-        [System.Security.SecuritySafeCriticalAttribute]
-#endif
     public readonly struct ActivitySpanId : IEquatable<ActivitySpanId>
     {
         private readonly string? _hexString;
diff --git a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/ActivityCreationOptions.cs b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/ActivityCreationOptions.cs
index 5deab8f9544f91..5737392650a657 100644
--- a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/ActivityCreationOptions.cs
+++ b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/ActivityCreationOptions.cs
@@ -114,9 +114,6 @@ internal ActivityCreationOptions(ActivitySource source, string name, T parent, A
 
         public ActivityTagsCollection SamplingTags
         {
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-            [System.Security.SecuritySafeCriticalAttribute]
-#endif
             get
             {
                 if (_samplerTags == null)
@@ -131,9 +128,6 @@ public ActivityTagsCollection SamplingTags
 
         public ActivityTraceId TraceId
         {
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-            [System.Security.SecuritySafeCriticalAttribute]
-#endif
             get
             {
                 if (Parent is ActivityContext && IdFormat == ActivityIdFormat.W3C && _context == default)
@@ -154,14 +148,7 @@ public ActivityTraceId TraceId
         /// </summary>
         public string? TraceState
         {
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-            [System.Security.SecuritySafeCriticalAttribute]
-#endif
             get => _traceState;
-
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-            [System.Security.SecuritySafeCriticalAttribute]
-#endif
             init
             {
                 _traceState = value;
@@ -169,9 +156,6 @@ public string? TraceState
         }
 
         // SetTraceState is to set the _traceState without the need of copying the whole structure.
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-        [System.Security.SecuritySafeCriticalAttribute]
-#endif
         internal void SetTraceState(string? traceState) => Unsafe.AsRef(in _traceState) = traceState;
 
         /// <summary>
diff --git a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/Counter.cs b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/Counter.cs
index 4a8cff4392d652..bb14c06b2c164c 100644
--- a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/Counter.cs
+++ b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/Counter.cs
@@ -13,9 +13,6 @@ namespace System.Diagnostics.Metrics
     /// <remarks>
     /// This class supports only the following generic parameter types: <see cref="byte" />, <see cref="short" />, <see cref="int" />, <see cref="long" />, <see cref="float" />, <see cref="double" />, and <see cref="decimal" />
     /// </remarks>
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-    [System.Security.SecuritySafeCriticalAttribute]
-#endif
     public sealed class Counter<T> : Instrument<T> where T : struct
     {
         internal Counter(Meter meter, string name, string? unit, string? description) : base(meter, name, unit, description)
diff --git a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/Histogram.cs b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/Histogram.cs
index f14cd8586e95e0..73eeda8c8ac69b 100644
--- a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/Histogram.cs
+++ b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/Histogram.cs
@@ -13,9 +13,6 @@ namespace System.Diagnostics.Metrics
     /// <remarks>
     /// This class supports only the following generic parameter types: <see cref="byte" />, <see cref="short" />, <see cref="int" />, <see cref="long" />, <see cref="float" />, <see cref="double" />, and <see cref="decimal" />
     /// </remarks>
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-        [System.Security.SecuritySafeCriticalAttribute]
-#endif
     public sealed class Histogram<T> : Instrument<T> where T : struct
     {
         internal Histogram(Meter meter, string name, string? unit, string? description) : base(meter, name, unit, description)
diff --git a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/Instrument.cs b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/Instrument.cs
index 4d16ef4bb99470..8d867045006663 100644
--- a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/Instrument.cs
+++ b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/Instrument.cs
@@ -8,9 +8,6 @@ namespace System.Diagnostics.Metrics
     /// <summary>
     /// Base class of all Metrics Instrument classes
     /// </summary>
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-        [System.Security.SecuritySafeCriticalAttribute]
-#endif
     public abstract class Instrument
     {
         internal static KeyValuePair<string, object?>[] EmptyTags => Array.Empty<KeyValuePair<string, object?>>();
diff --git a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/Instrument.netfx.cs b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/Instrument.netfx.cs
index 990735f023ee51..f04dc0d9d11d84 100644
--- a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/Instrument.netfx.cs
+++ b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/Instrument.netfx.cs
@@ -12,9 +12,6 @@ namespace System.Diagnostics.Metrics
     /// <remarks>
     /// This class supports only the following generic parameter types: <see cref="byte" />, <see cref="short" />, <see cref="int" />, <see cref="long" />, <see cref="float" />, <see cref="double" />, and <see cref="decimal" />
     /// </remarks>
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-        [System.Security.SecuritySafeCriticalAttribute]
-#endif
     public abstract partial class Instrument<T> : Instrument where T : struct
     {
         [ThreadStatic]
diff --git a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/Measurement.cs b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/Measurement.cs
index 00b398503fa81a..49db3c86f8dbf1 100644
--- a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/Measurement.cs
+++ b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/Measurement.cs
@@ -9,9 +9,6 @@ namespace System.Diagnostics.Metrics
     /// Measurement stores one observed metrics value and its associated tags. This type is used by Observable instruments' Observe() method when reporting current measurements.
     /// with the associated tags.
     /// </summary>
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-        [System.Security.SecuritySafeCriticalAttribute]
-#endif
     public readonly struct Measurement<T> where T : struct
     {
         private readonly KeyValuePair<string, object?>[] _tags;
diff --git a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/Meter.cs b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/Meter.cs
index 8332e5de79d8eb..431272393a0d3a 100644
--- a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/Meter.cs
+++ b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/Meter.cs
@@ -10,9 +10,6 @@ namespace System.Diagnostics.Metrics
     /// <summary>
     /// Meter is the class responsible for creating and tracking the Instruments.
     /// </summary>
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-        [System.Security.SecuritySafeCriticalAttribute]
-#endif
     public class Meter : IDisposable
     {
         private static readonly List<Meter> s_allMeters = new List<Meter>();
diff --git a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/MeterListener.cs b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/MeterListener.cs
index 165b31371a8e01..6c3d38f0b6aea2 100644
--- a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/MeterListener.cs
+++ b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/MeterListener.cs
@@ -14,9 +14,6 @@ namespace System.Diagnostics.Metrics
     /// <summary>
     /// MeterListener is class used to listen to the metrics instrument measurements recording.
     /// </summary>
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-        [System.Security.SecuritySafeCriticalAttribute]
-#endif
     public sealed class MeterListener : IDisposable
     {
         // We use LikedList here so we don't have to take any lock while iterating over the list as we always hold on a node which be either valid or null.
diff --git a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/ObservableCounter.cs b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/ObservableCounter.cs
index 4a360a25082133..651b4f5b6e3519 100644
--- a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/ObservableCounter.cs
+++ b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/ObservableCounter.cs
@@ -13,9 +13,6 @@ namespace System.Diagnostics.Metrics
     /// <remarks>
     /// This class supports only the following generic parameter types: <see cref="byte" />, <see cref="short" />, <see cref="int" />, <see cref="long" />, <see cref="float" />, <see cref="double" />, and <see cref="decimal" />
     /// </remarks>
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-        [System.Security.SecuritySafeCriticalAttribute]
-#endif
     public sealed class ObservableCounter<T> : ObservableInstrument<T> where T : struct
     {
         private object _callback;
diff --git a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/ObservableGauge.cs b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/ObservableGauge.cs
index f73845a1148443..6e659a56d68a0f 100644
--- a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/ObservableGauge.cs
+++ b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/ObservableGauge.cs
@@ -13,9 +13,6 @@ namespace System.Diagnostics.Metrics
     /// <remarks>
     /// This class supports only the following generic parameter types: <see cref="byte" />, <see cref="short" />, <see cref="int" />, <see cref="long" />, <see cref="float" />, <see cref="double" />, and <see cref="decimal" />
     /// </remarks>
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-        [System.Security.SecuritySafeCriticalAttribute]
-#endif
     public sealed class ObservableGauge<T> : ObservableInstrument<T> where T : struct
     {
         private object _callback;
diff --git a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/ObservableInstrument.cs b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/ObservableInstrument.cs
index 7e76ac3bd264c1..79cc57314a8e99 100644
--- a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/ObservableInstrument.cs
+++ b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/ObservableInstrument.cs
@@ -12,9 +12,6 @@ namespace System.Diagnostics.Metrics
     /// <remarks>
     /// This class supports only the following generic parameter types: <see cref="byte" />, <see cref="short" />, <see cref="int" />, <see cref="long" />, <see cref="float" />, <see cref="double" />, and <see cref="decimal" />
     /// </remarks>
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-        [System.Security.SecuritySafeCriticalAttribute]
-#endif
     public abstract class ObservableInstrument<T> : Instrument where T : struct
     {
         /// <summary>
@@ -41,9 +38,6 @@ protected ObservableInstrument(Meter meter, string name, string? unit, string? d
         public override bool IsObservable => true;
 
         // Will be called from MeterListener.RecordObservableInstruments for each observable instrument.
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-        [System.Security.SecuritySafeCriticalAttribute]
-#endif
         internal override void Observe(MeterListener listener)
         {
             object? state = GetSubscriptionState(listener);
diff --git a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/ObservableUpDownCounter.cs b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/ObservableUpDownCounter.cs
index 32ea7255ba4063..1589930bdbc25f 100644
--- a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/ObservableUpDownCounter.cs
+++ b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/ObservableUpDownCounter.cs
@@ -13,9 +13,6 @@ namespace System.Diagnostics.Metrics
     /// <remarks>
     /// This class supports only the following generic parameter types: <see cref="byte" />, <see cref="short" />, <see cref="int" />, <see cref="long" />, <see cref="float" />, <see cref="double" />, and <see cref="decimal" />
     /// </remarks>
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-        [System.Security.SecuritySafeCriticalAttribute]
-#endif
     public sealed class ObservableUpDownCounter<T> : ObservableInstrument<T> where T : struct
     {
         private object _callback;
diff --git a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/TagList.cs b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/TagList.cs
index bc1d02525895a8..159f74338fc4da 100644
--- a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/TagList.cs
+++ b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/TagList.cs
@@ -24,9 +24,6 @@ namespace System.Diagnostics
     /// Using more than eight tags will cause allocating memory to store the tags.
     /// Public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
     /// </remarks>
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-    [System.Security.SecuritySafeCriticalAttribute]
-#endif
     [StructLayout(LayoutKind.Sequential)]
     public struct TagList : IList<KeyValuePair<string, object?>>, IReadOnlyList<KeyValuePair<string, object?>>
     {
diff --git a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/UpDownCounter.cs b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/UpDownCounter.cs
index 88a11cd12851dc..8a908e9d665950 100644
--- a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/UpDownCounter.cs
+++ b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Metrics/UpDownCounter.cs
@@ -12,9 +12,6 @@ namespace System.Diagnostics.Metrics
     /// <remarks>
     /// This class supports only the following generic parameter types: <see cref="byte" />, <see cref="short" />, <see cref="int" />, <see cref="long" />, <see cref="float" />, <see cref="double" />, and <see cref="decimal" />
     /// </remarks>
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-    [System.Security.SecuritySafeCriticalAttribute]
-#endif
     public sealed class UpDownCounter<T> : Instrument<T> where T : struct
     {
         internal UpDownCounter(Meter meter, string name, string? unit, string? description) : base(meter, name, unit, description)
diff --git a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/RandomNumberGenerator.cs b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/RandomNumberGenerator.cs
index dfb8c50bb7499c..351e8ce6ad7e76 100644
--- a/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/RandomNumberGenerator.cs
+++ b/src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/RandomNumberGenerator.cs
@@ -14,9 +14,6 @@ internal sealed class RandomNumberGenerator
 
         public static RandomNumberGenerator Current => t_random ??= new RandomNumberGenerator();
 
-#if ALLOW_PARTIALLY_TRUSTED_CALLERS
-        [System.Security.SecuritySafeCriticalAttribute]
-#endif
         public unsafe RandomNumberGenerator()
         {
             do