diff --git a/generators/java/generator-utils/src/main/java/com/fern/java/utils/CasingConfiguration.java b/generators/java/generator-utils/src/main/java/com/fern/java/utils/CasingConfiguration.java
index d664f0aee384..ee3e3ff6c365 100644
--- a/generators/java/generator-utils/src/main/java/com/fern/java/utils/CasingConfiguration.java
+++ b/generators/java/generator-utils/src/main/java/com/fern/java/utils/CasingConfiguration.java
@@ -59,6 +59,7 @@ public final class CasingConfiguration {
             "else",
             "enum",
             "extends",
+            "false",
             "final",
             "finally",
             "float",
@@ -73,6 +74,7 @@ public final class CasingConfiguration {
             "long",
             "native",
             "new",
+            "null",
             "package",
             "private",
             "protected",
@@ -88,6 +90,7 @@ public final class CasingConfiguration {
             "throw",
             "throws",
             "transient",
+            "true",
             "try",
             "void",
             "volatile",
diff --git a/generators/java/generator-utils/src/test/java/com/fern/java/utils/CasingConfigurationTest.java b/generators/java/generator-utils/src/test/java/com/fern/java/utils/CasingConfigurationTest.java
index 4da8755bfb64..7ff5aba627d9 100644
--- a/generators/java/generator-utils/src/test/java/com/fern/java/utils/CasingConfigurationTest.java
+++ b/generators/java/generator-utils/src/test/java/com/fern/java/utils/CasingConfigurationTest.java
@@ -957,4 +957,24 @@ private static CasingConfiguration buildConfig(boolean smartCasing, String langu
         root.set("casingsConfig", casingsConfig);
         return CasingConfiguration.fromIrJson(root);
     }
+
+    // ===== keyword sanitization: Java literals =====
+
+    @Nested
+    class JavaLiteralKeywordTests {
+
+        @ParameterizedTest
+        @CsvSource({"'null',null_", "'true',true_", "'false',false_"})
+        void computeName_escapesJavaLiterals(String input, String expectedSafeName) {
+            CasingConfiguration config = buildConfig(true, "java", null);
+            CasingConfiguration.NameParts parts = config.computeName(input);
+            assertThat(parts.camelSafe).isEqualTo(expectedSafeName);
+        }
+
+        @Test
+        void computeName_ordinaryKeywordStillEscaped() {
+            CasingConfiguration config = buildConfig(true, "java", null);
+            assertThat(config.computeName("default").camelSafe).isEqualTo("default_");
+        }
+    }
 }
diff --git a/generators/java/sdk/changes/unreleased/fix-null-true-false-discriminator.yml b/generators/java/sdk/changes/unreleased/fix-null-true-false-discriminator.yml
new file mode 100644
index 000000000000..54358ea2a22c
--- /dev/null
+++ b/generators/java/sdk/changes/unreleased/fix-null-true-false-discriminator.yml
@@ -0,0 +1,11 @@
+# yaml-language-server: $schema=../../../../../fern-changes-yml.schema.json
+
+- summary: |
+    Escape the Java literals `null`, `true`, and `false` when they're used as a
+    discriminated union's discriminator value. Previously the generated Java
+    identifier was left unescaped (e.g. a static factory method literally named
+    `null`), which JavaPoet rejected with `not a valid name: null`, aborting
+    generation. The identifier is now escaped to `null_`/`true_`/`false_`
+    (matching the existing convention for other reserved words like `static`),
+    while the serialized discriminator value is unchanged.
+  type: fix