diff --git a/src/main/java/com/google/api/generator/gapic/composer/ResourceNameHelperClassComposer.java b/src/main/java/com/google/api/generator/gapic/composer/ResourceNameHelperClassComposer.java
index a9b3275bb9..652c8488d6 100644
--- a/src/main/java/com/google/api/generator/gapic/composer/ResourceNameHelperClassComposer.java
+++ b/src/main/java/com/google/api/generator/gapic/composer/ResourceNameHelperClassComposer.java
@@ -312,6 +312,18 @@ private static List<MethodDefinition> createConstructorMethods(
                 .setValueExpr(checkNotNullExpr)
                 .build());
       }
+      // Initialize the rest to null.
+      ValueExpr nullExpr = ValueExpr.withValue(NullObjectValue.create());
+      for (String token : getTokenSet(tokenHierarchies)) {
+        if (tokens.contains(token)) {
+          continue;
+        }
+        bodyExprs.add(
+            AssignmentExpr.builder()
+                .setVariableExpr(patternTokenVarExprs.get(token))
+                .setValueExpr(nullExpr)
+                .build());
+      }
 
       if (hasVariants) {
         AssignmentExpr pathTemplateAssignExpr =
diff --git a/src/test/java/com/google/api/generator/gapic/composer/ResourceNameHelperClassComposerTest.java b/src/test/java/com/google/api/generator/gapic/composer/ResourceNameHelperClassComposerTest.java
index cfcfa1bd63..75911fcffb 100644
--- a/src/test/java/com/google/api/generator/gapic/composer/ResourceNameHelperClassComposerTest.java
+++ b/src/test/java/com/google/api/generator/gapic/composer/ResourceNameHelperClassComposerTest.java
@@ -245,6 +245,8 @@ public void generateResourceNameClass_testingSessionOnePattern() {
           + "  private FoobarName(Builder builder) {\n"
           + "    project = Preconditions.checkNotNull(builder.getProject());\n"
           + "    foobar = Preconditions.checkNotNull(builder.getFoobar());\n"
+          + "    variant = null;\n"
+          + "    barFoo = null;\n"
           + "    pathTemplate = PROJECT_FOOBAR;\n"
           + "  }\n"
           + "\n"
@@ -252,17 +254,23 @@ public void generateResourceNameClass_testingSessionOnePattern() {
           + "    project = Preconditions.checkNotNull(builder.getProject());\n"
           + "    variant = Preconditions.checkNotNull(builder.getVariant());\n"
           + "    foobar = Preconditions.checkNotNull(builder.getFoobar());\n"
+          + "    barFoo = null;\n"
           + "    pathTemplate = PROJECT_VARIANT_FOOBAR;\n"
           + "  }\n"
           + "\n"
           + "  private FoobarName(FoobarBuilder builder) {\n"
           + "    foobar = Preconditions.checkNotNull(builder.getFoobar());\n"
+          + "    project = null;\n"
+          + "    variant = null;\n"
+          + "    barFoo = null;\n"
           + "    pathTemplate = FOOBAR;\n"
           + "  }\n"
           + "\n"
           + "  private FoobarName(BarFooFoobarBuilder builder) {\n"
           + "    barFoo = Preconditions.checkNotNull(builder.getBarFoo());\n"
           + "    foobar = Preconditions.checkNotNull(builder.getFoobar());\n"
+          + "    project = null;\n"
+          + "    variant = null;\n"
           + "    pathTemplate = BAR_FOO_FOOBAR;\n"
           + "  }\n"
           + "\n"