diff --git a/openpgp/decrypt.go b/openpgp/decrypt.go
index f756f58..78b24aa 100644
--- a/openpgp/decrypt.go
+++ b/openpgp/decrypt.go
@@ -68,7 +68,7 @@ func (o *FastOpenPGP) decrypt(reader io.Reader, privateKey, passphrase string, s
 			return nil, fmt.Errorf("signature error: %w", md.SignatureError)
 		}
 
-		if md.SignedBy == nil {
+		if !md.IsSigned {
 			return nil, errors.New("message is not signed")
 		}
 
diff --git a/openpgp/verify.go b/openpgp/verify.go
index cdf32ef..6d7870c 100644
--- a/openpgp/verify.go
+++ b/openpgp/verify.go
@@ -86,7 +86,7 @@ func (o *FastOpenPGP) verifyDataBytes(signedData io.Reader, publicKey string, sh
 		return false, fmt.Errorf("invalid read message: %w", err)
 	}
 
-	if md.SignedBy == nil {
+	if !md.IsSigned {
 		return false, errors.New("message was not signed")
 	}