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+// Copyright 2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+////////////////////////////////////////////////////////////////////////////////
+
+#ifndef TINK_HYBRID_HYBRID_PUBLIC_KEY_H_
+#define TINK_HYBRID_HYBRID_PUBLIC_KEY_H_
+
+#include "absl/strings/string_view.h"
+#include "tink/hybrid/hybrid_parameters.h"
+#include "tink/key.h"
+
+namespace crypto {
+namespace tink {
+
+// Represents the encryption function for a hybrid encryption primitive.
+class HybridPublicKey : public Key {
+ public:
+  // Returns the bytes prefixed to every ciphertext generated by this key.
+  //
+  // In order to make key rotation more efficient, Tink allows every hybrid
+  // public key to have an associated ciphertext output prefix. When decrypting
+  // a ciphertext, only keys with a matching prefix have to be tried.
+  //
+  // See https://developers.google.com/tink/wire-format#tink_output_prefix for
+  // more background information on Tink output prefixes.
+  virtual absl::string_view GetOutputPrefix() const = 0;
+
+  const HybridParameters& GetParameters() const override = 0;
+
+  bool operator==(const Key& other) const override = 0;
+};
+
+}  // namespace tink
+}  // namespace crypto
+
+#endif  // TINK_HYBRID_HYBRID_PUBLIC_KEY_H_