diff --git a/cmd/neofs-ir/main.go b/cmd/neofs-ir/main.go
index 33a6031e4..89ad6b499 100644
--- a/cmd/neofs-ir/main.go
+++ b/cmd/neofs-ir/main.go
@@ -100,7 +100,7 @@ func main() {
 	log.Info("application stopped")
 }
 
-func parsePublicKeysFromString(argument string) ([]keys.PublicKey, error) {
+func parsePublicKeysFromString(argument string) (keys.PublicKeys, error) {
 	publicKeysString := strings.Split(argument, ",")
 
 	return innerring.ParsePublicKeysFromStrings(publicKeysString)
diff --git a/pkg/innerring/innerring.go b/pkg/innerring/innerring.go
index 8a569ddfa..5f6cb9491 100644
--- a/pkg/innerring/innerring.go
+++ b/pkg/innerring/innerring.go
@@ -62,7 +62,7 @@ type (
 		key                  *ecdsa.PrivateKey
 		pubKey               []byte
 		contracts            *contracts
-		predefinedValidators []keys.PublicKey
+		predefinedValidators keys.PublicKeys
 
 		workers []func(context.Context)
 
@@ -664,7 +664,7 @@ func parseContracts(cfg *viper.Viper) (*contracts, error) {
 	return result, nil
 }
 
-func parsePredefinedValidators(cfg *viper.Viper) ([]keys.PublicKey, error) {
+func parsePredefinedValidators(cfg *viper.Viper) (keys.PublicKeys, error) {
 	publicKeyStrings := cfg.GetStringSlice("morph.validators")
 
 	return ParsePublicKeysFromStrings(publicKeyStrings)
@@ -672,8 +672,8 @@ func parsePredefinedValidators(cfg *viper.Viper) ([]keys.PublicKey, error) {
 
 // ParsePublicKeysFromStrings returns slice of neo public keys from slice
 // of hex encoded strings.
-func ParsePublicKeysFromStrings(pubKeys []string) ([]keys.PublicKey, error) {
-	publicKeys := make([]keys.PublicKey, 0, len(pubKeys))
+func ParsePublicKeysFromStrings(pubKeys []string) (keys.PublicKeys, error) {
+	publicKeys := make(keys.PublicKeys, 0, len(pubKeys))
 
 	for i := range pubKeys {
 		key, err := keys.NewPublicKeyFromString(pubKeys[i])
@@ -681,7 +681,7 @@ func ParsePublicKeysFromStrings(pubKeys []string) ([]keys.PublicKey, error) {
 			return nil, errors.Wrap(err, "can't decode public key")
 		}
 
-		publicKeys = append(publicKeys, *key)
+		publicKeys = append(publicKeys, key)
 	}
 
 	return publicKeys, nil
diff --git a/pkg/innerring/invoke/alphabet.go b/pkg/innerring/invoke/alphabet.go
index 935241a50..615de3c7e 100644
--- a/pkg/innerring/invoke/alphabet.go
+++ b/pkg/innerring/invoke/alphabet.go
@@ -22,15 +22,10 @@ func AlphabetEmit(cli *client.Client, con util.Uint160) error {
 }
 
 // AlphabetVote invokes vote method on alphabet contract.
-func AlphabetVote(cli *client.Client, con util.Uint160, epoch uint64, keys []keys.PublicKey) error {
+func AlphabetVote(cli *client.Client, con util.Uint160, epoch uint64, keys keys.PublicKeys) error {
 	if cli == nil {
 		return client.ErrNilClient
 	}
 
-	binaryKeys := make([][]byte, 0, len(keys))
-	for i := range keys {
-		binaryKeys = append(binaryKeys, keys[i].Bytes())
-	}
-
-	return cli.NotaryInvoke(con, voteMethod, int64(epoch), binaryKeys)
+	return cli.NotaryInvoke(con, voteMethod, int64(epoch), keys)
 }
diff --git a/pkg/innerring/state.go b/pkg/innerring/state.go
index 1a7a3a491..612a958b7 100644
--- a/pkg/innerring/state.go
+++ b/pkg/innerring/state.go
@@ -65,7 +65,7 @@ func (s *Server) AlphabetIndex() int {
 	return int(index)
 }
 
-func (s *Server) voteForSidechainValidator(validators []keys.PublicKey) error {
+func (s *Server) voteForSidechainValidator(validators keys.PublicKeys) error {
 	index := s.InnerRingIndex()
 	if s.contracts.alphabet.indexOutOfRange(index) {
 		s.log.Info("ignore validator vote: node not in alphabet range")
@@ -96,7 +96,7 @@ func (s *Server) voteForSidechainValidator(validators []keys.PublicKey) error {
 // InitAndVoteForSidechainValidator is a public function to use outside of
 // inner ring daemon execution. It initialize inner ring structure with data
 // from blockchain and then calls vote method on corresponding alphabet contract.
-func (s *Server) InitAndVoteForSidechainValidator(validators []keys.PublicKey) error {
+func (s *Server) InitAndVoteForSidechainValidator(validators keys.PublicKeys) error {
 	err := s.initConfigFromBlockchain()
 	if err != nil {
 		return err