diff --git a/proto-docs/refs.md b/proto-docs/refs.md
index e9e46d9..3ce5f0e 100644
--- a/proto-docs/refs.md
+++ b/proto-docs/refs.md
@@ -148,6 +148,7 @@ Signature of something in NeoFS.
 | ----- | ---- | ----- | ----------- |
 | key | [bytes](#bytes) |  | Public key used for signing |
 | sign | [bytes](#bytes) |  | Signature |
+| scheme | [SignatureScheme](#neo.fs.v2.refs.SignatureScheme) |  | Scheme contains digital signature scheme identifier. |
 
 
 <a name="neo.fs.v2.refs.SubnetID"></a>
@@ -194,6 +195,19 @@ Checksum algorithm type.
 | SHA256 | 2 | SHA-256 |
 
 
+
+<a name="neo.fs.v2.refs.SignatureScheme"></a>
+
+### SignatureScheme
+Signature scheme describes digital signing scheme used for (key, signature) pair.
+
+| Name | Number | Description |
+| ---- | ------ | ----------- |
+| UNSPECIFIED | 0 | Unknown. The default interpretation depends on a particular structure type. |
+| ECDSA_SHA512 | 1 | ECDSA with SHA-512 hashing (FIPS 186-3). |
+| ECDSA_RFC6979_SHA256 | 2 | Deterministic ECDSA with SHA-256 hashing (RFC 6979) |
+
+
  <!-- end enums -->
 
 
diff --git a/refs/types.proto b/refs/types.proto
index 9675026..908a76c 100644
--- a/refs/types.proto
+++ b/refs/types.proto
@@ -105,6 +105,18 @@ message Signature {
   bytes key = 1 [json_name = "key"];
   // Signature
   bytes sign = 2 [json_name = "signature"];
+  // Scheme contains digital signature scheme identifier.
+  SignatureScheme scheme = 3 [json_name = "scheme"];
+}
+
+// Signature scheme describes digital signing scheme used for (key, signature) pair.
+enum SignatureScheme {
+  // Unknown. The default interpretation depends on a particular structure type.
+  UNSPECIFIED = 0;
+  // ECDSA with SHA-512 hashing (FIPS 186-3).
+  ECDSA_SHA512 = 1;
+  // Deterministic ECDSA with SHA-256 hashing (RFC 6979)
+  ECDSA_RFC6979_SHA256 = 2;
 }
 
 // Checksum algorithm type.