diff --git a/constants/annotation_flags.h b/constants/annotation_flags.h
new file mode 100644
index 0000000..d2731da
--- /dev/null
+++ b/constants/annotation_flags.h
@@ -0,0 +1,26 @@
+// Copyright 2019 PDFium 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 CONSTANTS_ANNOTATION_FLAGS_H_
+#define CONSTANTS_ANNOTATION_FLAGS_H_
+
+namespace pdfium {
+namespace annotation_flags {
+
+// PDF 1.7 spec, table 8.16.
+constexpr uint32_t kInvisible = 1 << 0;
+constexpr uint32_t kHidden = 1 << 1;
+constexpr uint32_t kPrint = 1 << 2;
+constexpr uint32_t kNoZoom = 1 << 3;
+constexpr uint32_t kNoRotate = 1 << 4;
+constexpr uint32_t kNoView = 1 << 5;
+constexpr uint32_t kReadOnly = 1 << 6;
+constexpr uint32_t kLocked = 1 << 7;
+constexpr uint32_t kToggleNoView = 1 << 8;
+constexpr uint32_t kLockedContents = 1 << 9;
+
+}  // namespace annotation_flags
+}  // namespace pdfium
+
+#endif  // CONSTANTS_ANNOTATION_FLAGS_H_