diff --git a/build/source_list.bzl b/build/source_list.bzl
index d61599a..f150e2e 100644
--- a/build/source_list.bzl
+++ b/build/source_list.bzl
@@ -397,8 +397,6 @@
     "quic/platform/api/quic_stack_trace.h",
     "quic/platform/api/quic_testvalue.h",
     "quic/platform/api/quic_thread.h",
-    "spdy/core/hpack/hpack_encoder.h",
-    "spdy/core/spdy_bitmasks.h",
     "spdy/core/spdy_protocol.h",
     "web_transport/complete_buffer_visitor.h",
     "web_transport/encapsulated/encapsulated_web_transport.h",
diff --git a/build/source_list.gni b/build/source_list.gni
index b7b50aa..7e203c9 100644
--- a/build/source_list.gni
+++ b/build/source_list.gni
@@ -397,8 +397,6 @@
     "src/quiche/quic/platform/api/quic_stack_trace.h",
     "src/quiche/quic/platform/api/quic_testvalue.h",
     "src/quiche/quic/platform/api/quic_thread.h",
-    "src/quiche/spdy/core/hpack/hpack_encoder.h",
-    "src/quiche/spdy/core/spdy_bitmasks.h",
     "src/quiche/spdy/core/spdy_protocol.h",
     "src/quiche/web_transport/complete_buffer_visitor.h",
     "src/quiche/web_transport/encapsulated/encapsulated_web_transport.h",
diff --git a/build/source_list.json b/build/source_list.json
index f8f2861..9391a94 100644
--- a/build/source_list.json
+++ b/build/source_list.json
@@ -396,8 +396,6 @@
     "quiche/quic/platform/api/quic_stack_trace.h",
     "quiche/quic/platform/api/quic_testvalue.h",
     "quiche/quic/platform/api/quic_thread.h",
-    "quiche/spdy/core/hpack/hpack_encoder.h",
-    "quiche/spdy/core/spdy_bitmasks.h",
     "quiche/spdy/core/spdy_protocol.h",
     "quiche/web_transport/complete_buffer_visitor.h",
     "quiche/web_transport/encapsulated/encapsulated_web_transport.h",
diff --git a/quiche/spdy/core/hpack/hpack_encoder.h b/quiche/spdy/core/hpack/hpack_encoder.h
deleted file mode 100644
index 8e746c8..0000000
--- a/quiche/spdy/core/hpack/hpack_encoder.h
+++ /dev/null
@@ -1,12 +0,0 @@
-// Copyright 2014 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef QUICHE_SPDY_CORE_HPACK_HPACK_ENCODER_H_
-#define QUICHE_SPDY_CORE_HPACK_HPACK_ENCODER_H_
-
-#include "quiche/http2/hpack/hpack_encoder.h"
-
-// TODO(b/234438854): remove this file once Envoy has migrated to the new target
-
-#endif  // QUICHE_SPDY_CORE_HPACK_HPACK_ENCODER_H_
diff --git a/quiche/spdy/core/spdy_bitmasks.h b/quiche/spdy/core/spdy_bitmasks.h
deleted file mode 100644
index ae12b55..0000000
--- a/quiche/spdy/core/spdy_bitmasks.h
+++ /dev/null
@@ -1,10 +0,0 @@
-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef QUICHE_SPDY_CORE_SPDY_BITMASKS_H_
-#define QUICHE_SPDY_CORE_SPDY_BITMASKS_H_
-
-#include "quiche/http2/core/spdy_bitmasks.h"
-
-#endif  // QUICHE_SPDY_CORE_SPDY_BITMASKS_H_