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diff --git a/private_join_and_compute/util/elgamal_proto_util.cc b/private_join_and_compute/util/elgamal_proto_util.cc
new file mode 100644
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+++ b/private_join_and_compute/util/elgamal_proto_util.cc
@@ -0,0 +1,76 @@
+/*
+ * Copyright 2019 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
+ *
+ *     https://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.
+ */
+
+#include "private_join_and_compute/util/elgamal_proto_util.h"
+
+#include <memory>
+#include <utility>
+
+namespace private_join_and_compute::elgamal_proto_util {
+
+StatusOr<ElGamalPublicKey> SerializePublicKey(
+    const elgamal::PublicKey& public_key_struct) {
+  ElGamalPublicKey public_key_proto;
+  ASSIGN_OR_RETURN(auto serialized_g, public_key_struct.g.ToBytesCompressed());
+  public_key_proto.set_g(serialized_g);
+  ASSIGN_OR_RETURN(auto serialized_y, public_key_struct.y.ToBytesCompressed());
+  public_key_proto.set_y(serialized_y);
+  return public_key_proto;
+}
+
+StatusOr<ElGamalCiphertext> SerializeCiphertext(
+    const elgamal::Ciphertext& ciphertext_struct) {
+  ElGamalCiphertext ciphertext_proto;
+  ASSIGN_OR_RETURN(auto serialized_u, ciphertext_struct.u.ToBytesCompressed());
+  ciphertext_proto.set_u(serialized_u);
+  ASSIGN_OR_RETURN(auto serialized_e, ciphertext_struct.e.ToBytesCompressed());
+  ciphertext_proto.set_e(serialized_e);
+  return ciphertext_proto;
+}
+
+StatusOr<ElGamalSecretKey> SerializePrivateKey(
+    const elgamal::PrivateKey& private_key_struct) {
+  ElGamalSecretKey private_key_proto;
+  private_key_proto.set_x(private_key_struct.x.ToBytes());
+  return private_key_proto;
+}
+
+StatusOr<std::unique_ptr<elgamal::PublicKey>> DeserializePublicKey(
+    const ECGroup* ec_group, const ElGamalPublicKey& public_key_proto) {
+  ASSIGN_OR_RETURN(ECPoint public_key_struct_g,
+                   ec_group->CreateECPoint(public_key_proto.g()));
+  ASSIGN_OR_RETURN(ECPoint public_key_struct_y,
+                   ec_group->CreateECPoint(public_key_proto.y()));
+  return absl::WrapUnique(new elgamal::PublicKey(
+      {std::move(public_key_struct_g), std::move(public_key_struct_y)}));
+}
+
+StatusOr<std::unique_ptr<elgamal::PrivateKey>> DeserializePrivateKey(
+    Context* context, const ElGamalSecretKey& private_key_proto) {
+  BigNum x = context->CreateBigNum(private_key_proto.x());
+  return absl::WrapUnique(new elgamal::PrivateKey({std::move(x)}));
+}
+
+StatusOr<elgamal::Ciphertext> DeserializeCiphertext(
+    const ECGroup* ec_group, const ElGamalCiphertext& ciphertext_proto) {
+  ASSIGN_OR_RETURN(ECPoint ciphertext_struct_u,
+                   ec_group->CreateECPoint(ciphertext_proto.u()));
+  ASSIGN_OR_RETURN(ECPoint ciphertext_struct_e,
+                   ec_group->CreateECPoint(ciphertext_proto.e()));
+  return elgamal::Ciphertext{std::move(ciphertext_struct_u),
+                             std::move(ciphertext_struct_e)};
+}
+
+}  // namespace private_join_and_compute::elgamal_proto_util