diff --git a/src/libraries/System.Memory/ref/System.Memory.Forwards.cs b/src/libraries/System.Memory/ref/System.Memory.Forwards.cs
index e79102cfcd350..88d911fa08d8b 100644
--- a/src/libraries/System.Memory/ref/System.Memory.Forwards.cs
+++ b/src/libraries/System.Memory/ref/System.Memory.Forwards.cs
@@ -11,3 +11,4 @@
 [assembly: System.Runtime.CompilerServices.TypeForwardedTo(typeof(System.Buffers.MemoryManager<>))]
 [assembly: System.Runtime.CompilerServices.TypeForwardedTo(typeof(System.Buffers.OperationStatus))]
 [assembly: System.Runtime.CompilerServices.TypeForwardedTo(typeof(System.Buffers.Text.Base64))]
+[assembly: System.Runtime.CompilerServices.TypeForwardedTo(typeof(System.Runtime.InteropServices.MemoryMarshal))]
diff --git a/src/libraries/System.Memory/ref/System.Memory.cs b/src/libraries/System.Memory/ref/System.Memory.cs
index bc4e19712a310..f7b1f5f48d0f7 100644
--- a/src/libraries/System.Memory/ref/System.Memory.cs
+++ b/src/libraries/System.Memory/ref/System.Memory.cs
@@ -700,39 +700,6 @@ public static partial class Utf8Parser
         public static bool TryParse(System.ReadOnlySpan<byte> source, out ulong value, out int bytesConsumed, char standardFormat = '\0') { throw null; }
     }
 }
-namespace System.Runtime.InteropServices
-{
-    public static partial class MemoryMarshal
-    {
-        public static System.ReadOnlySpan<byte> AsBytes<T>(System.ReadOnlySpan<T> span) where T : struct { throw null; }
-        public static System.Span<byte> AsBytes<T>(System.Span<T> span) where T : struct { throw null; }
-        public static System.Memory<T> AsMemory<T>(System.ReadOnlyMemory<T> memory) { throw null; }
-        public static ref readonly T AsRef<T>(System.ReadOnlySpan<byte> span) where T : struct { throw null; }
-        public static ref T AsRef<T>(System.Span<byte> span) where T : struct { throw null; }
-        public static System.ReadOnlySpan<TTo> Cast<TFrom, TTo>(System.ReadOnlySpan<TFrom> span) where TFrom : struct where TTo : struct { throw null; }
-        public static System.Span<TTo> Cast<TFrom, TTo>(System.Span<TFrom> span) where TFrom : struct where TTo : struct { throw null; }
-        public static System.Memory<T> CreateFromPinnedArray<T>(T[]? array, int start, int length) { throw null; }
-        public static System.ReadOnlySpan<T> CreateReadOnlySpan<T>(scoped ref readonly T reference, int length) { throw null; }
-        [System.CLSCompliant(false)]
-        public static unsafe ReadOnlySpan<byte> CreateReadOnlySpanFromNullTerminated(byte* value) { throw null; }
-        [System.CLSCompliant(false)]
-        public static unsafe ReadOnlySpan<char> CreateReadOnlySpanFromNullTerminated(char* value) { throw null; }
-        public static System.Span<T> CreateSpan<T>(scoped ref T reference, int length) { throw null; }
-        public static ref T GetArrayDataReference<T>(T[] array) { throw null; }
-        public static ref byte GetArrayDataReference(System.Array array) { throw null; }
-        public static ref T GetReference<T>(System.ReadOnlySpan<T> span) { throw null; }
-        public static ref T GetReference<T>(System.Span<T> span) { throw null; }
-        public static T Read<T>(System.ReadOnlySpan<byte> source) where T : struct { throw null; }
-        public static System.Collections.Generic.IEnumerable<T> ToEnumerable<T>(System.ReadOnlyMemory<T> memory) { throw null; }
-        public static bool TryGetArray<T>(System.ReadOnlyMemory<T> memory, out System.ArraySegment<T> segment) { throw null; }
-        public static bool TryGetMemoryManager<T, TManager>(System.ReadOnlyMemory<T> memory, [System.Diagnostics.CodeAnalysis.NotNullWhenAttribute(true)] out TManager? manager) where TManager : System.Buffers.MemoryManager<T> { throw null; }
-        public static bool TryGetMemoryManager<T, TManager>(System.ReadOnlyMemory<T> memory, [System.Diagnostics.CodeAnalysis.NotNullWhenAttribute(true)] out TManager? manager, out int start, out int length) where TManager : System.Buffers.MemoryManager<T> { throw null; }
-        public static bool TryGetString(System.ReadOnlyMemory<char> memory, [System.Diagnostics.CodeAnalysis.NotNullWhenAttribute(true)] out string? text, out int start, out int length) { throw null; }
-        public static bool TryRead<T>(System.ReadOnlySpan<byte> source, out T value) where T : struct { throw null; }
-        public static bool TryWrite<T>(System.Span<byte> destination, in T value) where T : struct { throw null; }
-        public static void Write<T>(System.Span<byte> destination, in T value) where T : struct { }
-    }
-}
 namespace System.Text
 {
     public ref partial struct SpanLineEnumerator
diff --git a/src/libraries/System.Runtime/ref/System.Runtime.cs b/src/libraries/System.Runtime/ref/System.Runtime.cs
index db49bbfb30de2..b5ecc14826bfa 100644
--- a/src/libraries/System.Runtime/ref/System.Runtime.cs
+++ b/src/libraries/System.Runtime/ref/System.Runtime.cs
@@ -14034,6 +14034,36 @@ public enum LayoutKind
         Explicit = 2,
         Auto = 3,
     }
+    public static partial class MemoryMarshal
+    {
+        public static System.ReadOnlySpan<byte> AsBytes<T>(System.ReadOnlySpan<T> span) where T : struct { throw null; }
+        public static System.Span<byte> AsBytes<T>(System.Span<T> span) where T : struct { throw null; }
+        public static System.Memory<T> AsMemory<T>(System.ReadOnlyMemory<T> memory) { throw null; }
+        public static ref readonly T AsRef<T>(System.ReadOnlySpan<byte> span) where T : struct { throw null; }
+        public static ref T AsRef<T>(System.Span<byte> span) where T : struct { throw null; }
+        public static System.ReadOnlySpan<TTo> Cast<TFrom, TTo>(System.ReadOnlySpan<TFrom> span) where TFrom : struct where TTo : struct { throw null; }
+        public static System.Span<TTo> Cast<TFrom, TTo>(System.Span<TFrom> span) where TFrom : struct where TTo : struct { throw null; }
+        public static System.Memory<T> CreateFromPinnedArray<T>(T[]? array, int start, int length) { throw null; }
+        public static System.ReadOnlySpan<T> CreateReadOnlySpan<T>(scoped ref readonly T reference, int length) { throw null; }
+        [System.CLSCompliant(false)]
+        public static unsafe ReadOnlySpan<byte> CreateReadOnlySpanFromNullTerminated(byte* value) { throw null; }
+        [System.CLSCompliant(false)]
+        public static unsafe ReadOnlySpan<char> CreateReadOnlySpanFromNullTerminated(char* value) { throw null; }
+        public static System.Span<T> CreateSpan<T>(scoped ref T reference, int length) { throw null; }
+        public static ref T GetArrayDataReference<T>(T[] array) { throw null; }
+        public static ref byte GetArrayDataReference(System.Array array) { throw null; }
+        public static ref T GetReference<T>(System.ReadOnlySpan<T> span) { throw null; }
+        public static ref T GetReference<T>(System.Span<T> span) { throw null; }
+        public static T Read<T>(System.ReadOnlySpan<byte> source) where T : struct { throw null; }
+        public static System.Collections.Generic.IEnumerable<T> ToEnumerable<T>(System.ReadOnlyMemory<T> memory) { throw null; }
+        public static bool TryGetArray<T>(System.ReadOnlyMemory<T> memory, out System.ArraySegment<T> segment) { throw null; }
+        public static bool TryGetMemoryManager<T, TManager>(System.ReadOnlyMemory<T> memory, [System.Diagnostics.CodeAnalysis.NotNullWhenAttribute(true)] out TManager? manager) where TManager : System.Buffers.MemoryManager<T> { throw null; }
+        public static bool TryGetMemoryManager<T, TManager>(System.ReadOnlyMemory<T> memory, [System.Diagnostics.CodeAnalysis.NotNullWhenAttribute(true)] out TManager? manager, out int start, out int length) where TManager : System.Buffers.MemoryManager<T> { throw null; }
+        public static bool TryGetString(System.ReadOnlyMemory<char> memory, [System.Diagnostics.CodeAnalysis.NotNullWhenAttribute(true)] out string? text, out int start, out int length) { throw null; }
+        public static bool TryRead<T>(System.ReadOnlySpan<byte> source, out T value) where T : struct { throw null; }
+        public static bool TryWrite<T>(System.Span<byte> destination, in T value) where T : struct { throw null; }
+        public static void Write<T>(System.Span<byte> destination, in T value) where T : struct { }
+    }
     public readonly partial struct OSPlatform : System.IEquatable<System.Runtime.InteropServices.OSPlatform>
     {
         private readonly object _dummy;