diff --git a/src/main/java/com/google/devtools/build/lib/rules/proto/ProtoConfiguration.java b/src/main/java/com/google/devtools/build/lib/rules/proto/ProtoConfiguration.java
index 51fb38fec267df..f7a536bbaeafe7 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/proto/ProtoConfiguration.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/proto/ProtoConfiguration.java
@@ -171,7 +171,7 @@ public static class Options extends FragmentOptions {
 
     @Option(
         name = "incompatible_blacklisted_protos_requires_proto_info",
-        defaultValue = "false",
+        defaultValue = "true",
         documentationCategory = OptionDocumentationCategory.UNDOCUMENTED,
         effectTags = {OptionEffectTag.LOADING_AND_ANALYSIS},
         metadataTags = {
diff --git a/src/test/java/com/google/devtools/build/lib/rules/proto/ProtoLangToolchainTest.java b/src/test/java/com/google/devtools/build/lib/rules/proto/ProtoLangToolchainTest.java
index d6f1583ca716f7..c9e32316d6dc88 100644
--- a/src/test/java/com/google/devtools/build/lib/rules/proto/ProtoLangToolchainTest.java
+++ b/src/test/java/com/google/devtools/build/lib/rules/proto/ProtoLangToolchainTest.java
@@ -142,6 +142,9 @@ public void protoToolchainBlacklistTransitiveProtos() throws Exception {
 
   @Test
   public void protoToolchainMixedBlacklist() throws Exception {
+    // Tests legacy behaviour.
+    useConfiguration("--incompatible_blacklisted_protos_requires_proto_info=false");
+
     scratch.file(
         "third_party/x/BUILD",
         TestConstants.LOAD_PROTO_LIBRARY,