diff --git a/docs/reference.md b/docs/reference.md
index 0c7600c..6a03917 100644
--- a/docs/reference.md
+++ b/docs/reference.md
@@ -117,6 +117,7 @@
     *   [cflags_objcc: [string list] Flags passed to the Objective C++ compiler.](#var_cflags_objcc)
     *   [check_includes: [boolean] Controls whether a target's files are checked.](#var_check_includes)
     *   [check_includes_strict: [boolean] Controls whether strict include checking is enforced.](#var_check_includes_strict)
+    *   [collect_validations_metadata: [bool] Collect metadata values from validations deps.](#var_collect_validations_metadata)
     *   [complete_static_lib: [boolean] Links all deps into a static library.](#var_complete_static_lib)
     *   [configs: [label list] Configs applying to this target or config.](#var_configs)
     *   [contents: Contents to write to file.](#var_contents)
@@ -558,6 +559,7 @@
   cflags_c [--blame]
   cflags_cc [--blame]
   check_includes
+  collect_validations_metadata
   configs [--tree] (see below)
   data_keys
   defines [--blame]
@@ -2162,6 +2164,9 @@
 
   Collected metadata, if specified, will be returned in postorder of
   dependencies. See the example for details.
+
+  By default, validations dependencies are never visited by metadata collection,
+  but setting `collect_validations_metadata = true` changes this behavior.
 ```
 
 #### **Variables**
@@ -2174,7 +2179,7 @@
            output_extension, output_name, public, sources, testonly,
            visibility
   Generated file: contents, data_keys, rebase, walk_keys, output_conversion,
-                  outputs
+                  outputs, collect_validations_metadata
 ```
 
 #### **Example (metadata collection)**
@@ -5784,6 +5789,22 @@
     ...
   }
 ```
+### <a name="var_collect_validations_metadata"></a>**collect_validations_metadata**: Collect metadata values from validations deps&nbsp;[Back to Top](#gn-reference)
+
+```
+  A boolean flag for generated_file() targets. When true, a metadata walk
+  will visit validations dependencies (and their transitive dependencies,
+  including other validations ones) and collect metadata from them, unless
+  there are explicit barriers to prevent this.
+
+  When false (the default) the metadata walk will ignore validations
+  deps, to avoid inserting unexpected results in the result.
+
+  The default value can be changed by setting
+  'experimental_collect_validations_metadata = true' in the .gn file,
+  but this feature is temporary and will be removed in the future. See
+  https://gn.issues.chromium.org/566346002 for details.
+```
 ### <a name="var_complete_static_lib"></a>**complete_static_lib**: [boolean] Links all deps into a static library.&nbsp;[Back to Top](#gn-reference)
 
 ```
diff --git a/misc/vim/syntax/gn.vim b/misc/vim/syntax/gn.vim
index 2719560..5ca6a2e 100644
--- a/misc/vim/syntax/gn.vim
+++ b/misc/vim/syntax/gn.vim
@@ -45,7 +45,7 @@
 syn keyword     gnVariable all_dependent_configs allow_circular_includes_from
 syn keyword     gnVariable args arflags asmflags assert_no_deps
 syn keyword     gnVariable cflags cflags_c cflags_cc cflags_objc cflags_objcc
-syn keyword     gnVariable check_includes complete_static_lib configs
+syn keyword     gnVariable check_includes collect_validations_metadata complete_static_lib configs
 syn keyword     gnVariable data data_deps data_keys defines depfile deps
 syn keyword     gnVariable framework_dirs frameworks include_dirs inputs ldflags
 syn keyword     gnVariable lib_dirs libs output_extension output_name outputs
diff --git a/src/gn/command_desc.cc b/src/gn/command_desc.cc
index fc6fa93..d1e004a 100644
--- a/src/gn/command_desc.cc
+++ b/src/gn/command_desc.cc
@@ -305,6 +305,7 @@
           {variables::kDataKeys, DefaultHandler},
           {variables::kRebase, DefaultHandler},
           {variables::kWalkKeys, DefaultHandler},
+          {variables::kCollectValidationsMetadata, DefaultHandler},
           {variables::kWeakFrameworks, DefaultHandler},
           {variables::kWeakLibraries, DefaultHandler},
           {variables::kWriteOutputConversion, DefaultHandler},
@@ -407,6 +408,7 @@
   HandleProperty(variables::kLibDirs, handler_map, v, dict);
   HandleProperty(variables::kDataKeys, handler_map, v, dict);
   HandleProperty(variables::kRebase, handler_map, v, dict);
+  HandleProperty(variables::kCollectValidationsMetadata, handler_map, v, dict);
   HandleProperty(variables::kRustflags, handler_map, v, dict);
   HandleProperty(variables::kWalkKeys, handler_map, v, dict);
   HandleProperty(variables::kWeakFrameworks, handler_map, v, dict);
@@ -514,6 +516,7 @@
   cflags_c [--blame]
   cflags_cc [--blame]
   check_includes
+  collect_validations_metadata
   configs [--tree] (see below)
   data_keys
   defines [--blame]
diff --git a/src/gn/desc_builder.cc b/src/gn/desc_builder.cc
index a9f46f3..e04af12 100644
--- a/src/gn/desc_builder.cc
+++ b/src/gn/desc_builder.cc
@@ -584,6 +584,10 @@
           keys.GetList().push_back(base::Value(k));
         res->SetKey(variables::kWalkKeys, std::move(keys));
       }
+      if (what(variables::kCollectValidationsMetadata)) {
+        res->SetKey(variables::kCollectValidationsMetadata,
+                    base::Value(target_->collect_validations_metadata()));
+      }
     }
 
     if (what(variables::kDeps))
diff --git a/src/gn/functions_target.cc b/src/gn/functions_target.cc
index c5e3e2e..d7edcbe 100644
--- a/src/gn/functions_target.cc
+++ b/src/gn/functions_target.cc
@@ -987,12 +987,15 @@
   Collected metadata, if specified, will be returned in postorder of
   dependencies. See the example for details.
 
+  By default, validations dependencies are never visited by metadata collection,
+  but setting `collect_validations_metadata = true` changes this behavior.
+
 Variables
 
 )" DEPENDENT_CONFIG_VARS DEPS_VARS GENERAL_TARGET_VARS
 
     R"(  Generated file: contents, data_keys, rebase, walk_keys, output_conversion,
-                  outputs
+                  outputs, collect_validations_metadata
 
 Example (metadata collection)
 
diff --git a/src/gn/generated_file_target_generator.cc b/src/gn/generated_file_target_generator.cc
index 0a92122..a034562 100644
--- a/src/gn/generated_file_target_generator.cc
+++ b/src/gn/generated_file_target_generator.cc
@@ -36,6 +36,10 @@
 
   if (!FillContents())
     return;
+
+  if (!FillCollectValidationsMetadata())
+    return;
+
   if (!FillDataKeys())
     return;
 
@@ -81,6 +85,30 @@
   return true;
 }
 
+bool GeneratedFileTargetGenerator::FillCollectValidationsMetadata() {
+  std::string_view variable = variables::kCollectValidationsMetadata;
+
+  bool flag_value = false;
+
+  const Value* value = scope_->GetValue(variable, true);
+  if (value) {
+    if (!value->VerifyTypeIs(Value::BOOLEAN, err_))
+      return false;
+
+    if (!IsMetadataCollectionTarget(variable, value->origin()))
+      return false;
+
+    flag_value = value->boolean_value();
+  } else if (!contents_defined_) {
+    flag_value = target_->settings()
+                     ->build_settings()
+                     ->experimental_collect_validations_metadata();
+  }
+
+  target_->set_collect_validations_metadata(flag_value);
+  return true;
+}
+
 bool GeneratedFileTargetGenerator::FillOutputConversion() {
   const Value* value =
       scope_->GetValue(variables::kWriteOutputConversion, true);
diff --git a/src/gn/generated_file_target_generator.h b/src/gn/generated_file_target_generator.h
index c240023..ba5db34 100644
--- a/src/gn/generated_file_target_generator.h
+++ b/src/gn/generated_file_target_generator.h
@@ -27,6 +27,7 @@
   bool FillGeneratedFileOutput();
   bool FillOutputConversion();
   bool FillContents();
+  bool FillCollectValidationsMetadata();
   bool FillDataKeys();
   bool FillWalkKeys();
   bool FillRebase();
diff --git a/src/gn/target.cc b/src/gn/target.cc
index dc0d539..91ecb76 100644
--- a/src/gn/target.cc
+++ b/src/gn/target.cc
@@ -1288,12 +1288,14 @@
   MetadataWalker(const KeyList& data_keys,
                  const KeyList& walk_keys,
                  const SourceDir& rebase_dir,
+                 bool collect_validations_metadata,
                  std::vector<Value>* result,
                  TargetSet& targets_walked,
                  Err& err)
       : data_keys_(data_keys),
         walk_keys_(walk_keys),
         rebase_dir_(rebase_dir),
+        collect_validations_metadata_(collect_validations_metadata),
         result_(result),
         targets_walked_(targets_walked),
         err_(err) {}
@@ -1339,11 +1341,13 @@
               return false;
           }
         }
-        for (const auto& dep : target.validations()) {
-          // If we haven't walked this dep yet, go down into it.
-          if (targets_walked_.add(dep.ptr)) {
-            if (!Walk(*dep.ptr, false))
-              return false;
+        if (collect_validations_metadata_) {
+          for (const auto& dep : target.validations()) {
+            // If we haven't walked this dep yet, go down into it.
+            if (targets_walked_.add(dep.ptr)) {
+              if (!Walk(*dep.ptr, false))
+                return false;
+            }
           }
         }
 
@@ -1379,7 +1383,7 @@
           break;
         }
       }
-      if (!found_next) {
+      if (!found_next && collect_validations_metadata_) {
         for (const auto& dep : target.validations()) {
           // Match against the label with the toolchain.
           if (dep.label.Matches(next_label, toolchain_label)) {
@@ -1418,6 +1422,7 @@
   const KeyList& data_keys_;
   const KeyList& walk_keys_;
   const SourceDir& rebase_dir_;
+  bool collect_validations_metadata_;
   std::vector<Value>* result_;
   TargetSet& targets_walked_;
   Err& err_;
@@ -1432,8 +1437,9 @@
                          std::vector<Value>* result,
                          TargetSet* targets_walked,
                          Err* err) const {
-  MetadataWalker walker(data_keys, walk_keys, rebase_dir, result,
-                        *targets_walked, *err);
+  MetadataWalker walker(data_keys, walk_keys, rebase_dir,
+                        collect_validations_metadata_, result, *targets_walked,
+                        *err);
   return walker.Walk(*this, deps_only);
 }
 
diff --git a/src/gn/target.h b/src/gn/target.h
index 4023062..4403b76 100644
--- a/src/gn/target.h
+++ b/src/gn/target.h
@@ -472,6 +472,13 @@
     user_friendly_location_ = location;
   }
 
+  bool collect_validations_metadata() const {
+    return collect_validations_metadata_;
+  }
+  void set_collect_validations_metadata(bool value) {
+    collect_validations_metadata_ = value;
+  }
+
   // Computes and returns the outputs of this target expressed as SourceFiles.
   //
   // For binary target this depends on the tool for this target so the toolchain
@@ -577,6 +584,7 @@
   bool check_includes_ = true;
   bool check_includes_strict_ = false;
   bool complete_static_lib_ = false;
+  bool collect_validations_metadata_ = false;
   std::vector<std::string> data_;
   std::unique_ptr<BundleData> bundle_data_;
   OutputFile write_runtime_deps_output_;
diff --git a/src/gn/target_unittest.cc b/src/gn/target_unittest.cc
index 7ed4055..5518761 100644
--- a/src/gn/target_unittest.cc
+++ b/src/gn/target_unittest.cc
@@ -1545,10 +1545,10 @@
   EXPECT_EQ("input.modulemap.pcm", output[0].value()) << output[0].value();
 }
 
-TEST(TargetTest, CollectMetadataWithValidation) {
+TEST(TargetTest, CollectMetadataMustIgnoreValidationByDefault) {
   TestWithScope setup;
 
-  TestTarget a(setup, "//foo:a", Target::SOURCE_SET);
+  TestTarget a(setup, "//foo:a", Target::GENERATED_FILE);
   Value a_expected(nullptr, Value::LIST);
   a_expected.list_value().push_back(Value(nullptr, "foo"));
   a.metadata().contents().emplace("walk", a_expected);
@@ -1569,6 +1569,35 @@
                 &err);
   EXPECT_SUCCESS(err);
 
+  std::vector<Value> expected = {Value(nullptr, "foo")};
+  EXPECT_EQ(result, expected);
+}
+
+TEST(TargetTest, CollectValidationsMetadataFlag) {
+  TestWithScope setup;
+
+  TestTarget a(setup, "//foo:a", Target::GENERATED_FILE);
+  Value a_expected(nullptr, Value::LIST);
+  a_expected.list_value().push_back(Value(nullptr, "foo"));
+  a.metadata().contents().emplace("walk", a_expected);
+
+  TestTarget b(setup, "//foo:b", Target::SOURCE_SET);
+  Value b_expected(nullptr, Value::LIST);
+  b_expected.list_value().push_back(Value(nullptr, "bar"));
+  b.metadata().contents().emplace("walk", b_expected);
+
+  a.validations().push_back(LabelTargetPair(&b));
+  a.set_collect_validations_metadata(true);
+
+  std::vector<std::string> data_keys = {"walk"};
+  std::vector<std::string> walk_keys;
+  std::vector<Value> result;
+  TargetSet targets;
+  Err err;
+  a.GetMetadata(data_keys, walk_keys, SourceDir(), false, &result, &targets,
+                &err);
+  EXPECT_SUCCESS(err);
+
   std::vector<Value> expected = {Value(nullptr, "bar"), Value(nullptr, "foo")};
   EXPECT_EQ(result, expected);
 }
diff --git a/src/gn/variables.cc b/src/gn/variables.cc
index f3cf257..994322d 100644
--- a/src/gn/variables.cc
+++ b/src/gn/variables.cc
@@ -948,6 +948,28 @@
   }
 )";
 
+const char kCollectValidationsMetadata[] = "collect_validations_metadata";
+const char kCollectValidationsMetadata_HelpShort[] =
+    "collect_validations_metadata: [bool] Collect metadata values from "
+    "validations deps.";
+const char kCollectValidationsMetadata_Help[] =
+    R"(collect_validations_metadata: Collect metadata values from validations deps
+
+  A boolean flag for generated_file() targets. When true, a metadata walk
+  will visit validations dependencies (and their transitive dependencies,
+  including other validations ones) and collect metadata from them, unless
+  there are explicit barriers to prevent this.
+
+  When false (the default) the metadata walk will ignore validations
+  deps, to avoid inserting unexpected results in the result.
+
+  The default value can be changed by setting
+  'experimental_collect_validations_metadata = true' in the .gn file,
+  but this feature is temporary and will be removed in the future. See
+  https://gn.issues.chromium.org/566346002 for details.
+
+)";
+
 const char kCompleteStaticLib[] = "complete_static_lib";
 const char kCompleteStaticLib_HelpShort[] =
     "complete_static_lib: [boolean] Links all deps into a static library.";
@@ -2604,6 +2626,7 @@
     INSERT_VARIABLE(CflagsObjCC)
     INSERT_VARIABLE(CheckIncludes)
     INSERT_VARIABLE(CheckIncludesStrict)
+    INSERT_VARIABLE(CollectValidationsMetadata)
     INSERT_VARIABLE(CompleteStaticLib)
     INSERT_VARIABLE(Configs)
     INSERT_VARIABLE(Data)
diff --git a/src/gn/variables.h b/src/gn/variables.h
index 7e39f47..97c21b3 100644
--- a/src/gn/variables.h
+++ b/src/gn/variables.h
@@ -170,6 +170,10 @@
 extern const char kCheckIncludesStrict_HelpShort[];
 extern const char kCheckIncludesStrict_Help[];
 
+extern const char kCollectValidationsMetadata[];
+extern const char kCollectValidationsMetadata_HelpShort[];
+extern const char kCollectValidationsMetadata_Help[];
+
 extern const char kCompleteStaticLib[];
 extern const char kCompleteStaticLib_HelpShort[];
 extern const char kCompleteStaticLib_Help[];