diff --git a/java/server/src/org/openqa/selenium/grid/distributor/AddNode.java b/java/server/src/org/openqa/selenium/grid/distributor/AddNode.java
index 8a4d326b5afb2..bac26a106d747 100644
--- a/java/server/src/org/openqa/selenium/grid/distributor/AddNode.java
+++ b/java/server/src/org/openqa/selenium/grid/distributor/AddNode.java
@@ -52,7 +52,7 @@ class AddNode implements HttpHandler {
     this.distributor = Require.nonNull("Distributor", distributor);
     this.json = Require.nonNull("Json converter", json);
     this.httpFactory = Require.nonNull("HTTP Factory", httpFactory);
-    this.registrationSecret = registrationSecret;
+    this.registrationSecret = Require.nonNull("Registration secret", registrationSecret);
   }
 
   @Override
diff --git a/java/server/src/org/openqa/selenium/grid/distributor/Distributor.java b/java/server/src/org/openqa/selenium/grid/distributor/Distributor.java
index 20e7016057f31..3c546a1c581b0 100644
--- a/java/server/src/org/openqa/selenium/grid/distributor/Distributor.java
+++ b/java/server/src/org/openqa/selenium/grid/distributor/Distributor.java
@@ -135,6 +135,8 @@ protected Distributor(
     this.slotSelector = Require.nonNull("Slot selector", slotSelector);
     this.sessions = Require.nonNull("Session map", sessions);
 
+    Require.nonNull("Registration secret", registrationSecret);
+
     RequiresSecretFilter requiresSecret = new RequiresSecretFilter(registrationSecret);
 
     Json json = new Json();
diff --git a/java/server/src/org/openqa/selenium/grid/distributor/local/GridModel.java b/java/server/src/org/openqa/selenium/grid/distributor/local/GridModel.java
index 8cdcb31ad9c9f..8a34308ebb6e2 100644
--- a/java/server/src/org/openqa/selenium/grid/distributor/local/GridModel.java
+++ b/java/server/src/org/openqa/selenium/grid/distributor/local/GridModel.java
@@ -62,6 +62,7 @@ public class GridModel {
 
   public GridModel(EventBus events, Secret registrationSecret) {
     this.events = Require.nonNull("Event bus", events);
+    Require.nonNull("Registration secret", registrationSecret);
 
     events.addListener(NodeDrainStarted.listener(nodeId -> setAvailability(nodeId, DRAINING)));
     events.addListener(NodeDrainComplete.listener(this::remove));
@@ -101,9 +102,10 @@ public GridModel add(NodeStatus node) {
   }
 
   public GridModel refresh(Secret registrationSecret, NodeStatus status) {
+    Require.nonNull("Registration secret", registrationSecret);
     Require.nonNull("Node status", status);
 
-    Secret statusSecret = status.getRegistrationSecret() == null ? null : new Secret(status.getRegistrationSecret());
+    Secret statusSecret = new Secret(status.getRegistrationSecret());
     if (!Secret.matches(registrationSecret, statusSecret)) {
       LOG.severe(String.format("Node at %s failed to send correct registration secret. Node NOT refreshed.", status.getUri()));
       events.fire(new NodeRejectedEvent(status.getUri()));
@@ -261,7 +263,7 @@ private NodeStatus rewrite(NodeStatus status, Availability availability) {
       status.getMaxSessionCount(),
       status.getSlots(),
       availability,
-      status.getRegistrationSecret() == null ? null : new Secret(status.getRegistrationSecret()));
+      new Secret(status.getRegistrationSecret()));
   }
 
   private void release(SessionId id) {
@@ -365,7 +367,7 @@ private void amend(Availability availability, NodeStatus status, Slot slot) {
       status.getMaxSessionCount(),
       newSlots,
       status.getAvailability(),
-      status.getRegistrationSecret() == null ? null : new Secret(status.getRegistrationSecret())));
+      new Secret(status.getRegistrationSecret())));
   }
 
   private static class AvailabilityAndNode {
diff --git a/java/server/src/org/openqa/selenium/grid/distributor/local/LocalDistributor.java b/java/server/src/org/openqa/selenium/grid/distributor/local/LocalDistributor.java
index 511bef4fc38ea..237fbc004bb4c 100644
--- a/java/server/src/org/openqa/selenium/grid/distributor/local/LocalDistributor.java
+++ b/java/server/src/org/openqa/selenium/grid/distributor/local/LocalDistributor.java
@@ -131,9 +131,10 @@ public boolean isReady() {
   }
 
   private void register(Secret registrationSecret, NodeStatus status) {
+    Require.nonNull("Registration secret", registrationSecret);
     Require.nonNull("Node", status);
 
-    Secret nodeSecret = status.getRegistrationSecret() == null ? null : new Secret(status.getRegistrationSecret());
+    Secret nodeSecret = new Secret(status.getRegistrationSecret());
     if (!Secret.matches(registrationSecret, nodeSecret)) {
       LOG.severe(String.format("Node at %s failed to send correct registration secret. Node NOT registered.", status.getUri()));
       bus.fire(new NodeRejectedEvent(status.getUri()));
diff --git a/java/server/src/org/openqa/selenium/grid/node/Node.java b/java/server/src/org/openqa/selenium/grid/node/Node.java
index 56e3c4e925acc..a2124aaf7c4d3 100644
--- a/java/server/src/org/openqa/selenium/grid/node/Node.java
+++ b/java/server/src/org/openqa/selenium/grid/node/Node.java
@@ -110,6 +110,7 @@ protected Node(Tracer tracer, NodeId id, URI uri, Secret registrationSecret) {
     this.tracer = Require.nonNull("Tracer", tracer);
     this.id = Require.nonNull("Node id", id);
     this.uri = Require.nonNull("URI", uri);
+    Require.nonNull("Registration secret", registrationSecret);
 
     RequiresSecretFilter requiresSecret = new RequiresSecretFilter(registrationSecret);
 
diff --git a/java/server/src/org/openqa/selenium/grid/node/k8s/OneShotNode.java b/java/server/src/org/openqa/selenium/grid/node/k8s/OneShotNode.java
index 5fdb22b0911b6..218caf682062d 100644
--- a/java/server/src/org/openqa/selenium/grid/node/k8s/OneShotNode.java
+++ b/java/server/src/org/openqa/selenium/grid/node/k8s/OneShotNode.java
@@ -108,7 +108,7 @@ private OneShotNode(
     WebDriverInfo driverInfo) {
     super(tracer, id, uri, registrationSecret);
 
-    this.registrationSecret = registrationSecret;
+    this.registrationSecret = Require.nonNull("Registration secret", registrationSecret);
     this.events = Require.nonNull("Event bus", events);
     this.gridUri = Require.nonNull("Public Grid URI", gridUri);
     this.stereotype = ImmutableCapabilities.copyOf(Require.nonNull("Stereotype", stereotype));
diff --git a/java/server/src/org/openqa/selenium/grid/node/remote/RemoteNode.java b/java/server/src/org/openqa/selenium/grid/node/remote/RemoteNode.java
index a569d90db03c8..bf0f25a3a809d 100644
--- a/java/server/src/org/openqa/selenium/grid/node/remote/RemoteNode.java
+++ b/java/server/src/org/openqa/selenium/grid/node/remote/RemoteNode.java
@@ -84,11 +84,11 @@ public RemoteNode(
     this.externalUri = Require.nonNull("External URI", externalUri);
     this.capabilities = ImmutableSet.copyOf(capabilities);
 
-    this.client = Require
-        .nonNull("HTTP client factory", clientFactory).createClient(fromUri(externalUri));
+    this.client = Require.nonNull("HTTP client factory", clientFactory).createClient(fromUri(externalUri));
 
     this.healthCheck = new RemoteCheck();
 
+    Require.nonNull("Registration secret", registrationSecret);
     this.addSecret = new AddSecretFilter(registrationSecret);
   }
 
diff --git a/java/server/src/org/openqa/selenium/grid/security/AddSecretFilter.java b/java/server/src/org/openqa/selenium/grid/security/AddSecretFilter.java
index c6ceb3b8fea81..0eb0fbc33b6bb 100644
--- a/java/server/src/org/openqa/selenium/grid/security/AddSecretFilter.java
+++ b/java/server/src/org/openqa/selenium/grid/security/AddSecretFilter.java
@@ -17,6 +17,7 @@
 
 package org.openqa.selenium.grid.security;
 
+import org.openqa.selenium.internal.Require;
 import org.openqa.selenium.remote.http.Filter;
 import org.openqa.selenium.remote.http.HttpHandler;
 
@@ -26,13 +27,13 @@ public class AddSecretFilter implements Filter {
   private final Secret secret;
 
   public AddSecretFilter(Secret secret) {
-    this.secret = secret;
+    this.secret = Require.nonNull("Secret", secret);
   }
 
   @Override
   public HttpHandler apply(HttpHandler httpHandler) {
     return req -> {
-      if (secret != null && req.getHeader(HEADER_NAME) == null) {
+      if (req.getHeader(HEADER_NAME) == null) {
         req.addHeader(HEADER_NAME, secret.encode());
       }
 
diff --git a/java/server/src/org/openqa/selenium/grid/security/RequiresSecretFilter.java b/java/server/src/org/openqa/selenium/grid/security/RequiresSecretFilter.java
index f3630c823f90f..589f8323fdd47 100644
--- a/java/server/src/org/openqa/selenium/grid/security/RequiresSecretFilter.java
+++ b/java/server/src/org/openqa/selenium/grid/security/RequiresSecretFilter.java
@@ -37,7 +37,7 @@ public class RequiresSecretFilter implements Filter {
   private final Secret secret;
 
   public RequiresSecretFilter(Secret secret) {
-    this.secret = secret;
+    this.secret = Require.nonNull("Secret", secret);
   }
 
   @Override