diff --git a/src/JSInterop/Microsoft.JSInterop/src/IJSInProcessRuntime.cs b/src/JSInterop/Microsoft.JSInterop/src/IJSInProcessRuntime.cs
index 6da8d7f3a7..d1ccd639db 100644
--- a/src/JSInterop/Microsoft.JSInterop/src/IJSInProcessRuntime.cs
+++ b/src/JSInterop/Microsoft.JSInterop/src/IJSInProcessRuntime.cs
@@ -15,6 +15,6 @@ namespace Microsoft.JSInterop
         /// <param name="identifier">An identifier for the function to invoke. For example, the value <c>"someScope.someFunction"</c> will invoke the function <c>window.someScope.someFunction</c>.</param>
         /// <param name="args">JSON-serializable arguments.</param>
         /// <returns>An instance of <typeparamref name="T"/> obtained by JSON-deserializing the return value.</returns>
-        T Invoke<T>(string identifier, params object[] args);
+        T Invoke<T>(string identifier, params object?[]? args);
     }
 }
diff --git a/src/JSInterop/Microsoft.JSInterop/src/IJSRuntime.cs b/src/JSInterop/Microsoft.JSInterop/src/IJSRuntime.cs
index 26a7be400f..914811d8b4 100644
--- a/src/JSInterop/Microsoft.JSInterop/src/IJSRuntime.cs
+++ b/src/JSInterop/Microsoft.JSInterop/src/IJSRuntime.cs
@@ -22,7 +22,7 @@ namespace Microsoft.JSInterop
         /// <param name="identifier">An identifier for the function to invoke. For example, the value <c>"someScope.someFunction"</c> will invoke the function <c>window.someScope.someFunction</c>.</param>
         /// <param name="args">JSON-serializable arguments.</param>
         /// <returns>An instance of <typeparamref name="TValue"/> obtained by JSON-deserializing the return value.</returns>
-        ValueTask<TValue> InvokeAsync<TValue>(string identifier, object[] args);
+        ValueTask<TValue> InvokeAsync<TValue>(string identifier, object?[]? args);
 
         /// <summary>
         /// Invokes the specified JavaScript function asynchronously.
@@ -35,6 +35,6 @@ namespace Microsoft.JSInterop
         /// </param>
         /// <param name="args">JSON-serializable arguments.</param>
         /// <returns>An instance of <typeparamref name="TValue"/> obtained by JSON-deserializing the return value.</returns>
-        ValueTask<TValue> InvokeAsync<TValue>(string identifier, CancellationToken cancellationToken, object[] args);
+        ValueTask<TValue> InvokeAsync<TValue>(string identifier, CancellationToken cancellationToken, object?[]? args);
     }
 }
diff --git a/src/JSInterop/Microsoft.JSInterop/src/Infrastructure/DotNetDispatcher.cs b/src/JSInterop/Microsoft.JSInterop/src/Infrastructure/DotNetDispatcher.cs
index 30c1910143..1f8b5c9b5f 100644
--- a/src/JSInterop/Microsoft.JSInterop/src/Infrastructure/DotNetDispatcher.cs
+++ b/src/JSInterop/Microsoft.JSInterop/src/Infrastructure/DotNetDispatcher.cs
@@ -136,7 +136,7 @@ namespace Microsoft.JSInterop.Infrastructure
             Type[] parameterTypes;
             if (objectReference is null)
             {
-                assemblyKey = new AssemblyKey(assemblyName);
+                assemblyKey = new AssemblyKey(assemblyName!);
                 (methodInfo, parameterTypes) = GetCachedMethodInfo(assemblyKey, methodIdentifier);
             }
             else
diff --git a/src/JSInterop/Microsoft.JSInterop/src/Infrastructure/DotNetInvocationInfo.cs b/src/JSInterop/Microsoft.JSInterop/src/Infrastructure/DotNetInvocationInfo.cs
index 942fc34da0..bbec14337e 100644
--- a/src/JSInterop/Microsoft.JSInterop/src/Infrastructure/DotNetInvocationInfo.cs
+++ b/src/JSInterop/Microsoft.JSInterop/src/Infrastructure/DotNetInvocationInfo.cs
@@ -15,7 +15,7 @@ namespace Microsoft.JSInterop.Infrastructure
         /// <param name="methodIdentifier">The identifier of the method to be invoked.</param>
         /// <param name="dotNetObjectId">The object identifier for instance method calls.</param>
         /// <param name="callId">The call identifier.</param>
-        public DotNetInvocationInfo(string assemblyName, string methodIdentifier, long dotNetObjectId, string callId)
+        public DotNetInvocationInfo(string? assemblyName, string methodIdentifier, long dotNetObjectId, string? callId)
         {
             CallId = callId;
             AssemblyName = assemblyName;
@@ -27,7 +27,7 @@ namespace Microsoft.JSInterop.Infrastructure
         /// Gets the name of the assembly containing the method.
         /// Only one of <see cref="DotNetObjectId"/> or <see cref="AssemblyName"/> may be specified.
         /// </summary>
-        public string AssemblyName { get; }
+        public string? AssemblyName { get; }
 
         /// <summary>
         /// Gets the identifier of the method to be invoked. This is the value specified in the <see cref="JSInvokableAttribute"/>.
@@ -43,6 +43,6 @@ namespace Microsoft.JSInterop.Infrastructure
         /// <summary>
         /// Gets the call identifier. This value is <see langword="null"/> when the client does not expect a value to be returned.
         /// </summary>
-        public string CallId { get; }
+        public string? CallId { get; }
     }
 }
diff --git a/src/JSInterop/Microsoft.JSInterop/src/JSInProcessRuntime.cs b/src/JSInterop/Microsoft.JSInterop/src/JSInProcessRuntime.cs
index 5125cbd701..04ace4eb3a 100644
--- a/src/JSInterop/Microsoft.JSInterop/src/JSInProcessRuntime.cs
+++ b/src/JSInterop/Microsoft.JSInterop/src/JSInProcessRuntime.cs
@@ -19,7 +19,7 @@ namespace Microsoft.JSInterop
         /// <param name="args">JSON-serializable arguments.</param>
         /// <returns>An instance of <typeparamref name="TValue"/> obtained by JSON-deserializing the return value.</returns>
         [return: MaybeNull]
-        public TValue Invoke<TValue>(string identifier, params object[] args)
+        public TValue Invoke<TValue>(string identifier, params object?[]? args)
         {
             var resultJson = InvokeJS(identifier, JsonSerializer.Serialize(args, JsonSerializerOptions));
             if (resultJson is null)
diff --git a/src/JSInterop/Microsoft.JSInterop/src/JSRuntime.cs b/src/JSInterop/Microsoft.JSInterop/src/JSRuntime.cs
index b59e987686..ff11668dd7 100644
--- a/src/JSInterop/Microsoft.JSInterop/src/JSRuntime.cs
+++ b/src/JSInterop/Microsoft.JSInterop/src/JSRuntime.cs
@@ -62,7 +62,7 @@ namespace Microsoft.JSInterop
         /// <param name="identifier">An identifier for the function to invoke. For example, the value <c>"someScope.someFunction"</c> will invoke the function <c>window.someScope.someFunction</c>.</param>
         /// <param name="args">JSON-serializable arguments.</param>
         /// <returns>An instance of <typeparamref name="TValue"/> obtained by JSON-deserializing the return value.</returns>
-        public async ValueTask<TValue> InvokeAsync<TValue>(string identifier, object[] args)
+        public async ValueTask<TValue> InvokeAsync<TValue>(string identifier, object?[]? args)
         {
             if (DefaultAsyncTimeout.HasValue)
             {
@@ -85,7 +85,7 @@ namespace Microsoft.JSInterop
         /// </param>
         /// <param name="args">JSON-serializable arguments.</param>
         /// <returns>An instance of <typeparamref name="TValue"/> obtained by JSON-deserializing the return value.</returns>
-        public ValueTask<TValue> InvokeAsync<TValue>(string identifier, CancellationToken cancellationToken, object[] args)
+        public ValueTask<TValue> InvokeAsync<TValue>(string identifier, CancellationToken cancellationToken, object?[]? args)
         {
             var taskId = Interlocked.Increment(ref _nextPendingTaskId);
             var tcs = new TaskCompletionSource<TValue>(TaskContinuationOptions.RunContinuationsAsynchronously);