diff --git a/payload_generator/generate_delta_main.cc b/payload_generator/generate_delta_main.cc
index fe0a10b..8809e43 100644
--- a/payload_generator/generate_delta_main.cc
+++ b/payload_generator/generate_delta_main.cc
@@ -74,37 +74,6 @@
   }
 }
 
-bool ParseImageInfo(const string& channel,
-                    const string& board,
-                    const string& version,
-                    const string& key,
-                    const string& build_channel,
-                    const string& build_version,
-                    ImageInfo* image_info) {
-  // All of these arguments should be present or missing.
-  bool empty = channel.empty();
-
-  CHECK_EQ(channel.empty(), empty);
-  CHECK_EQ(board.empty(), empty);
-  CHECK_EQ(version.empty(), empty);
-  CHECK_EQ(key.empty(), empty);
-
-  if (empty)
-    return false;
-
-  image_info->set_channel(channel);
-  image_info->set_board(board);
-  image_info->set_version(version);
-  image_info->set_key(key);
-
-  image_info->set_build_channel(build_channel.empty() ? channel
-                                                      : build_channel);
-
-  image_info->set_build_version(build_version.empty() ? version
-                                                      : build_version);
-
-  return true;
-}
 
 void CalculateHashForSigning(const vector<int>& sizes,
                              const string& out_hash_file,
@@ -386,51 +355,6 @@
                "The maximum timestamp of the OS allowed to apply this "
                "payload.");
 
-  DEFINE_string(old_channel,
-                "",
-                "The channel for the old image. 'dev-channel', 'npo-channel', "
-                "etc. Ignored, except during delta generation.");
-  DEFINE_string(old_board,
-                "",
-                "The board for the old image. 'x86-mario', 'lumpy', "
-                "etc. Ignored, except during delta generation.");
-  DEFINE_string(
-      old_version, "", "The build version of the old image. 1.2.3, etc.");
-  DEFINE_string(old_key,
-                "",
-                "The key used to sign the old image. 'premp', 'mp', 'mp-v3',"
-                " etc");
-  DEFINE_string(old_build_channel,
-                "",
-                "The channel for the build of the old image. 'dev-channel', "
-                "etc, but will never contain special channels such as "
-                "'npo-channel'. Ignored, except during delta generation.");
-  DEFINE_string(old_build_version,
-                "",
-                "The version of the build containing the old image.");
-
-  DEFINE_string(new_channel,
-                "",
-                "The channel for the new image. 'dev-channel', 'npo-channel', "
-                "etc. Ignored, except during delta generation.");
-  DEFINE_string(new_board,
-                "",
-                "The board for the new image. 'x86-mario', 'lumpy', "
-                "etc. Ignored, except during delta generation.");
-  DEFINE_string(
-      new_version, "", "The build version of the new image. 1.2.3, etc.");
-  DEFINE_string(new_key,
-                "",
-                "The key used to sign the new image. 'premp', 'mp', 'mp-v3',"
-                " etc");
-  DEFINE_string(new_build_channel,
-                "",
-                "The channel for the build of the new image. 'dev-channel', "
-                "etc, but will never contain special channels such as "
-                "'npo-channel'. Ignored, except during delta generation.");
-  DEFINE_string(new_build_version,
-                "",
-                "The version of the build containing the new image.");
   DEFINE_string(new_postinstall_config_file,
                 "",
                 "A config file specifying postinstall related metadata. "
@@ -600,24 +524,6 @@
 
   CHECK(!FLAGS_out_file.empty());
 
-  // Ignore failures. These are optional arguments.
-  ParseImageInfo(FLAGS_new_channel,
-                 FLAGS_new_board,
-                 FLAGS_new_version,
-                 FLAGS_new_key,
-                 FLAGS_new_build_channel,
-                 FLAGS_new_build_version,
-                 &payload_config.target.image_info);
-
-  // Ignore failures. These are optional arguments.
-  ParseImageInfo(FLAGS_old_channel,
-                 FLAGS_old_board,
-                 FLAGS_old_version,
-                 FLAGS_old_key,
-                 FLAGS_old_build_channel,
-                 FLAGS_old_build_version,
-                 &payload_config.source.image_info);
-
   payload_config.rootfs_partition_size = FLAGS_rootfs_partition_size;
 
   if (payload_config.is_delta) {
diff --git a/payload_generator/payload_file.cc b/payload_generator/payload_file.cc
index b55d03c..aa9b4d3 100644
--- a/payload_generator/payload_file.cc
+++ b/payload_generator/payload_file.cc
@@ -64,13 +64,6 @@
   TEST_AND_RETURN_FALSE(config.version.Validate());
   major_version_ = config.version.major;
   manifest_.set_minor_version(config.version.minor);
-
-  if (!config.source.ImageInfoIsEmpty())
-    *(manifest_.mutable_old_image_info()) = config.source.image_info;
-
-  if (!config.target.ImageInfoIsEmpty())
-    *(manifest_.mutable_new_image_info()) = config.target.image_info;
-
   manifest_.set_block_size(config.block_size);
   manifest_.set_max_timestamp(config.max_timestamp);
 
diff --git a/payload_generator/payload_generation_config.cc b/payload_generator/payload_generation_config.cc
index 7158796..90d9f1b 100644
--- a/payload_generator/payload_generation_config.cc
+++ b/payload_generator/payload_generation_config.cc
@@ -103,7 +103,6 @@
 }
 
 bool ImageConfig::ValidateIsEmpty() const {
-  TEST_AND_RETURN_FALSE(ImageInfoIsEmpty());
   return partitions.empty();
 }
 
@@ -206,13 +205,6 @@
   return true;
 }
 
-bool ImageConfig::ImageInfoIsEmpty() const {
-  return image_info.board().empty() && image_info.key().empty() &&
-         image_info.channel().empty() && image_info.version().empty() &&
-         image_info.build_channel().empty() &&
-         image_info.build_version().empty();
-}
-
 PayloadVersion::PayloadVersion(uint64_t major_version, uint32_t minor_version) {
   major = major_version;
   minor = minor_version;
@@ -278,9 +270,6 @@
       TEST_AND_RETURN_FALSE(part.verity.IsEmpty());
     }
 
-    // If new_image_info is present, old_image_info must be present.
-    TEST_AND_RETURN_FALSE(source.ImageInfoIsEmpty() ==
-                          target.ImageInfoIsEmpty());
   } else {
     // All the "source" image fields must be empty for full payloads.
     TEST_AND_RETURN_FALSE(source.ValidateIsEmpty());
diff --git a/payload_generator/payload_generation_config.h b/payload_generator/payload_generation_config.h
index 32f1229..b7b2eb0 100644
--- a/payload_generator/payload_generation_config.h
+++ b/payload_generator/payload_generation_config.h
@@ -143,13 +143,6 @@
   // Validate |dynamic_partition_metadata| against |partitions|.
   bool ValidateDynamicPartitionMetadata() const;
 
-  // Returns whether the |image_info| field is empty.
-  bool ImageInfoIsEmpty() const;
-
-  // The ImageInfo message defined in the update_metadata.proto file describes
-  // the metadata of the image.
-  ImageInfo image_info;
-
   // The updated partitions.
   std::vector<PartitionConfig> partitions;
 
diff --git a/payload_generator/payload_properties.cc b/payload_generator/payload_properties.cc
index bc82eb7..bcf4fbd 100644
--- a/payload_generator/payload_properties.cc
+++ b/payload_generator/payload_properties.cc
@@ -47,8 +47,6 @@
 // These are needed by the Nebraska and devserver.
 const char kPayloadPropertyJsonPayloadSize[] = "size";
 const char kPayloadPropertyJsonIsDelta[] = "is_delta";
-const char kPayloadPropertyJsonTargetVersion[] = "target_version";
-const char kPayloadPropertyJsonSourceVersion[] = "source_version";
 }  // namespace
 
 PayloadProperties::PayloadProperties(const string& payload_path)
@@ -65,10 +63,6 @@
   properties.SetInteger(kPayloadPropertyJsonPayloadSize, payload_size_);
   properties.SetString(kPayloadPropertyJsonPayloadHash, payload_hash_);
   properties.SetBoolean(kPayloadPropertyJsonIsDelta, is_delta_);
-  properties.SetString(kPayloadPropertyJsonTargetVersion, target_version_);
-  if (is_delta_) {
-    properties.SetString(kPayloadPropertyJsonSourceVersion, source_version_);
-  }
 
   return base::JSONWriter::Write(properties, json_str);
 }
@@ -119,23 +113,11 @@
     metadata_signatures_ = base::JoinString(base64_signatures, ":");
   }
 
-  is_delta_ = manifest.has_old_image_info() ||
-              std::any_of(manifest.partitions().begin(),
+  is_delta_ = std::any_of(manifest.partitions().begin(),
                           manifest.partitions().end(),
                           [](const PartitionUpdate& part) {
                             return part.has_old_partition_info();
                           });
-
-  if (manifest.has_new_image_info()) {
-    target_version_ = manifest.new_image_info().version();
-  } else {
-    target_version_ = "99999.0.0";
-  }
-
-  // No need to set the source version if it was not a delta payload.
-  if (is_delta_ && manifest.has_old_image_info()) {
-    source_version_ = manifest.old_image_info().version();
-  }
   return true;
 }
 
diff --git a/payload_generator/payload_properties.h b/payload_generator/payload_properties.h
index 3b34511..846b181 100644
--- a/payload_generator/payload_properties.h
+++ b/payload_generator/payload_properties.h
@@ -62,9 +62,6 @@
   // Whether the payload is a delta (true) or full (false).
   bool is_delta_;
 
-  std::string target_version_;
-  std::string source_version_;
-
   DISALLOW_COPY_AND_ASSIGN(PayloadProperties);
 };
 
diff --git a/payload_generator/payload_properties_unittest.cc b/payload_generator/payload_properties_unittest.cc
index db3902c..a923379 100644
--- a/payload_generator/payload_properties_unittest.cc
+++ b/payload_generator/payload_properties_unittest.cc
@@ -57,8 +57,6 @@
     PayloadGenerationConfig config;
     config.version.major = kBrilloMajorPayloadVersion;
     config.version.minor = kSourceMinorPayloadVersion;
-    config.source.image_info.set_version("123.0.0");
-    config.target.image_info.set_version("456.7.8");
     PayloadFile payload;
     EXPECT_TRUE(payload.Init(config));
 
@@ -114,11 +112,9 @@
       "{"
       R"("is_delta":true,)"
       R"("metadata_signature":"",)"
-      R"("metadata_size":187,)"
-      R"("sha256_hex":"Rtrj9v3xXhrAi1741HAojtGxAQEOZ7mDyhzskIF4PJc=",)"
-      R"("size":233,)"
-      R"("source_version":"123.0.0",)"
-      R"("target_version":"456.7.8",)"
+      R"("metadata_size":165,)"
+      R"("sha256_hex":"cV7kfZBH3K0B6QJHxxykDh6b6x0WgVOmc63whPLOy7U=",)"
+      R"("size":211,)"
       R"("version":2)"
       "}";
   string json;
@@ -130,10 +126,10 @@
 // Validate the hash of file and metadata are within the output.
 TEST_F(PayloadPropertiesTest, GetPropertiesAsKeyValueTestHash) {
   constexpr char kKeyValueProperties[] =
-      "FILE_HASH=Rtrj9v3xXhrAi1741HAojtGxAQEOZ7mDyhzskIF4PJc=\n"
-      "FILE_SIZE=233\n"
-      "METADATA_HASH=kiXTexy/s2aPttf4+r8KRZWYZ6FYvwhU6rJGcnnI+U0=\n"
-      "METADATA_SIZE=187\n";
+      "FILE_HASH=cV7kfZBH3K0B6QJHxxykDh6b6x0WgVOmc63whPLOy7U=\n"
+      "FILE_SIZE=211\n"
+      "METADATA_HASH=aEKYyzJt2E8Gz8fzB+gmekN5mriotZCSq6R+kDfdeV4=\n"
+      "METADATA_SIZE=165\n";
   string key_value;
   EXPECT_TRUE(PayloadProperties{payload_file.path()}.GetPropertiesAsKeyValue(
       &key_value));